Peer-reviewed published papers

Below you'll find abstracts from published papers from our team and HCP collaborators, including observational studies regarding trends in Lumosity data and exploratory research involving subjects suffering from a variety of medical conditions. This content is for informational purposes only. Lumosity is not intended to diagnose, treat, cure, or prevent any disease. You should always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

2020

Alosco, M.L., Tripodis, Y., Baucom, Z.H., Mez, J., Stein, T.D., Martin, B., ... Stern, R. A. (2020). The Late Contributions of Repetitive Head Impacts and TBI to Depression Symptoms and Cognitions. doi:10.1212/WNL.0000000000010040

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Objective: To test the hypothesis that repetitive head impacts (RHIs), like those from contact sport play and traumatic brain injury (TBI) have long-term neuropsychiatric and cognitive consequences, we compared middle-age and older adult participants who reported a history of RHI and/or TBI with those without this history on measures of depression and cognition.

Methods: This cross-sectional study included 13,323 individuals (mean age, 61.95; 72.5% female) from the Brain Health Registry who completed online assessments, including the Ohio State University TBI Identification Method, the Geriatric Depression Scale (GDS-15), and the CogState Brief Battery and Lumos Labs NeuroCognitive Performance Tests. Inverse propensity-weighted linear regressions accounting for age, sex, race/ethnicity, and education tested the effects of RHI and TBI compared to a non-RHI/TBI group.

Results: A total of 725 participants reported RHI exposure (mostly contact sport play and abuse) and 7,277 reported TBI (n = 2,604 with loss of consciousness [LOC]). RHI (β, 1.24; 95% CI, 0.36–2.12), TBI without LOC (β, 0.43; 95% CI, 0.31–0.54), and TBI with LOC (β, 0.75; 95% CI, 0.59–0.91) corresponded to higher GDS-15 scores. While TBI with LOC had the most neuropsychological associations, TBI without LOC had a negative effect on CogState Identification (β, 0.004; 95% CI, 0.001–0.01) and CogState One Back Test (β, 0.004; 95% CI, 0.0002–0.01). RHI predicted worse CogState One Back Test scores (β, 0.02; 95% CI, −0.01 to 0.05). There were RHI × TBI interaction effects on several neuropsychological subtests, and participants who had a history of both RHI and TBI with LOC had the greatest depression symptoms and worse cognition.

Conclusions: RHI and TBI independently contributed to worse mid- to later-life neuropsychiatric and cognitive functioning.

Corti, C., Urgesi, C., Poggi, G., Strazzer, S., Borgatti, R., & Bardoni, A. (2020). Home-based cognitive training in pediatric patients with acquired brain injury: preliminary results on efficacy of a randomized clinical trial. Scientific Reports, 10(1), 1–15. doi:10.1038/s41598-020-57952-5

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Cognitive rehabilitation may compensate for cognitive deficits of children with acquired brain injury (ABI), capitalizing on the use-dependent plasticity of a developing brain. Remote computerized cognitive training (CCT) may be delivered to patients in ecological settings, ensuring rehabilitation continuity. This work evaluated cognitive and psychological adjustment outcomes of an 8-week multi-domain, home-based CCT (Lumosity Cognitive Training) in a sample of patients with ABI aged 11–16 years. Two groups of patients were engaged in five CCT sessions per week for eight weeks (40 sessions). According to a stepped-wedge research design, one group (Training-first Group) started the CCT immediately, whereas the other group (Waiting-first Group) started the CCT after a comparable time of waiting list. Changes after the training and after the waiting period were compared in the two groups. Both groups improved in visual-spatial working memory more after the training than after the waiting-list period. The Training-first group improved also in arithmetic calculation speed. Findings indicate that a multi-domain CCT can produce benefits in visual-spatial working memory, probably because, in accordance with previous research, computer games heavily tax visuo-spatial abilities. This suggests that the prolonged stimulation of the same cognitive ability may generate the greatest benefits in children with ABI.

Humeidan, M.L., Reyes, J.C., Mavarez-Martinez, A., Roeth, C., Nguyen, C.M., Sheridan, E., ... Bergese, S.D. (2020). Effect of Cognitive Prehabilitation on the Incidence of Postoperative Delirium Among Older Adults Undergoing Major Noncardiac Surgery: The Neurobics Randomized Clinical Trial. JAMA Surg. Published online November 11, 2020. doi:10.1001/jamasurg.2020.4371

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Importance: Postoperative delirium in older adults is a common and costly complication after surgery. Cognitive reserve affects the risk of postoperative delirium, and thus preoperative augmentation of reserve as a preventive technique is of vital interest.

Objective: To determine whether cognitive prehabilitation reduces the incidence of postoperative delirium among older adults.

Design, Setting, and Participants: This was a prospective, single-blinded randomized clinical trial conducted from March 2015 to August 2019 at the Ohio State University Wexner Medical Center in Columbus. Patients 60 years and older undergoing major, noncardiac, nonneurological surgery under general anesthesia, with an expected hospital stay of at least 72 hours, were eligible for trial inclusion. Patients were excluded for preoperative cognitive dysfunction and active depression.

Interventions: Participation in electronic, tablet-based preoperative cognitive exercise targeting memory, speed, attention, flexibility, and problem-solving functions.

Main Outcomes and Measures: The primary outcome was incidence of delirium between postoperative day 0 to day 7 or discharge, as measured by a brief Confusion Assessment Method, Memorial Delirium Assessment Scale, or a structured medical record review. Secondary outcomes compared delirium characteristics between patients in the intervention and control groups.

Results: Of the 699 patients approached for trial participation, 322 completed consent and 268 were randomized. Subsequently, 17 patients were excluded, leaving 251 patients in the primary outcome analysis. A total of 125 patients in the intervention group and 126 control patients were included in the final analysis (median [interquartile range] age, 67 [63-71] years; 163 women [64.9%]). Ninety-seven percent of the patients in the intervention group completed some brain exercise (median, 4.6 [interquartile range, 1.31-7.4] hours). The delirium rate among control participants was 23.0% (29 of 126). With intention-to-treat analysis, the delirium rate in the intervention group was 14.4% (18 of 125; P = .08). Post hoc analysis removed 4 patients who did not attempt any cognitive exercise from the intervention group, yielding a delirium rate of 13.2% (16 of 121; P = .04). Secondary analyses among patients with delirium showed no differences in postoperative delirium onset day or duration or total delirium-positive days across study groups.

Conclusions and Relevance: The intervention lowered delirium risk in patients who were at least minimally compliant. The ideal activities, timing, and effective dosage for cognitive exercise–based interventions to decrease postoperative delirium risk and burden need further study.

Trial Registration: ClinicalTrials.gov Identifier: NCT02230605

Mewton, L., Hodge, A., Gates, N., Visontay, R., Lees, B., & Teesson, M. (2020). A randomised double-blind trial of cognitive training for the prevention of psychopathology in at-risk youth. Behaviour Research and Therapy, 103672. doi:10.1016/j.brat.2020.103672

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Background: The aim of this study was to evaluate the effectiveness of online cognitive training as a means of reducing psychopathology in at-risk youth.

Methods: In a double-blind randomised controlled trial, 228 youths (mean age = 18.6, 74.6% female) were randomly allocated to either an intervention group (n = 114; online cognitive training focused on executive functioning) and a control group (n = 114; online cognitive training focused on other cognitive abilities). Participants were assessed online at baseline, post-training, 3-, 6- and 12-month follow-up. The primary outcome of the study was overall psychopathology as measured by the Strengths and Difficulties Questionnaire. Secondary outcomes were executive functioning ability (assessed using the n-back, trail-making and Stroop tasks), day-to-day functioning and risky drinking.

Results: Mixed model intention-to-treat analyses indicated that psychopathology increased and day-to-day functioning decreased, regardless of intervention group. Those in the intervention group improved more than those in the control group in terms of the n-back task, but this was not statistically significant after adjusting for multiple comparisons. There were no statistically significant effects on risky drinking, or the trail-making and Stroop tasks.

Conclusion: This study failed to provide evidence for the efficacy of cognitive training as a stand-alone intervention for psychopathology.

Ng, N. F., Schafer, R. J., Simone, C. M. & Osman, A. M. (2020). Perceptions of brain training: Public expectations of cognitive benefits from popular activities. Frontiers in Human Neuroscience, 14:15. doi:10.3389/fnhum.2020.00015

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Many popular activities are thought by the general public to improve cognitive function. Such expectations can influence how often people engage in these activities, as well as the scientific evaluation of their putative cognitive benefits, e.g., via placebo effects. Here, we gathered survey data about the public’s perceptions of nine different activities commonly thought to be cognitively stimulating, including “brain-training” games. Information was collected about the degree to which participants thought each activity was beneficial for improving cognitive function and how often they engaged in each activity. The patterns of correlation between ratings reveal details about the perception of cognitive benefits and its relation to engagement. They suggest that participants varied with respect to an overarching perception of the entire set of activities, which were perceived also as divided into three clusters. Frequency of engagement and perceived cognitive benefits were positively correlated across participants for each activity considered individually. But, when the activities were compared, the magnitude of their perceived benefits was not a good predictor of their frequency of engagement (and vice versa). Though small, there were systematic demographic differences. Women were more optimistic than men about cognitive benefits. Individual participants differed in the range of their ratings of benefit across activities, and these ranges were greater for younger than older participants, suggesting that perceptions of benefit are more differentiated among the young. Besides contributing to a better understanding of public expectations of cognitive benefits, the findings of this study are relevant to the critical evaluation of such benefits. Our survey can be viewed as providing an interface between expectations held by the general public and the design of studies examining the efficacy of cognitive training. The type of information it provides could be used in the selection of activities performed by an active control group, so that control activities match the treatment intervention as closely as possible with respect to such expectations.

O’Gara, B.P., Mueller, A., Gasangwa, D.V.I., Patxot, M., Shaefi, S., Khabbaz, K., ... & Subramaniam, B. (2020). Prevention of early postoperative decline: a randomized, controlled feasibility trial of perioperative cognitive training. Anesthesia & Analgesia, 130(3), 586-595. doi:10.1213/ANE.0000000000004469

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Background: Postoperative delirium and postoperative cognitive dysfunction (POCD) are common after cardiac surgery and contribute to an increased risk of postoperative complications, longer length of stay, and increased hospital mortality. Cognitive training (CT) may be able to durably improve cognitive reserve in areas deficient in delirium and POCD and, therefore, may potentially reduce the risk of these conditions. We sought to determine the feasibility and potential efficacy of a perioperative CT program to reduce the incidence of postoperative delirium and POCD in older cardiac surgery patients.

Methods: Randomized controlled trial at a single tertiary care center. Participants included 45 older adults age 60–90 undergoing cardiac surgery at least 10 days from enrollment. Participants were randomly assigned in a 1:1 fashion to either perioperative CT via a mobile device or a usual care control. The primary outcome of feasibility was evaluated by enrollment patterns and adherence to protocol. Secondary outcomes of postoperative delirium and POCD were assessed using the Confusion Assessment Method and the Montreal Cognitive Assessment, respectively. Patient satisfaction was assessed via a postoperative survey.

Results: Sixty-five percent of eligible patients were enrolled. Median (interquartile range [IQR]) adherence (as a percentage of prescribed minutes played) was 39% (20%–68%), 6% (0%–37%), and 19% (0%–56%) for the preoperative, immediate postoperative, and postdischarge periods, respectively. Median (IQR) training times were 245 (136–536), 18 (0–40), and 122 (0–281) minutes for each period, respectively. The incidence of postoperative delirium (CT group 5/20 [25%] versus control 3/20 [15%]; P = .69) and POCD (CT group 53% versus control 37%; P = .33) was not significantly different between groups for either outcome in this limited sample. CT participants reported a high level of agreement (on a scale of 0–100) with statements that the program was easy to use (median [IQR], 87 [75–97]) and enjoyable (85 [79–91]). CT participants agreed significantly more than controls that their memory (median [IQR], 75 [54–82] vs 51 [49–54]; P = .01) and thinking ability (median [IQR], 78 [64–83] vs 50 [41–68]; P = .01) improved as a result of their participation in the study.

Conclusions: A CT program designed for use in the preoperative period is an attractive target for future investigations of cognitive prehabilitation in older cardiac surgery patients. Changes in the functionality of the program and enrichment techniques may improve adherence in future trials. Further investigation is necessary to determine the potential efficacy of cognitive prehabilitation to reduce the risk of postoperative delirium and POCD.

Shaw, M., Pilloni, G., & Charvet, L. (2020). Delivering Transcranial Direct Current Stimulation Away from Clinic: Remotely Supervised tDCS. Military Medicine, 185, 319–325. doi:10.1093/milmed/usz348

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Introduction: To demonstrate the broad utility of the remotely supervised transcranial direct current stimulation (RS-tDCS) protocol developed to deliver at-home rehabilitation for individuals with multiple sclerosis (MS).

Methods: Stimulation delivered with the RS-tDCS protocol and paired with adaptive cognitive training was delivered to three different study groups of MS patients to determine the feasibility and tolerability of the protocol. The three studies each used consecutively increasing amounts of stimulation amperage (1.5, 2.0, and 2.5 mA, respectively) and session numbers (10, 20, and 40 sessions, respectively).

Results: High feasibility and tolerability of the stimulation were observed for n = 99 participants across three tDCS pilot studies.

Conclusions: RS-tDCS is feasible and tolerable for MS participants. The RS-tDCS protocol can be used to reach those in locations without clinic access and be paired with training or rehabilitation in locations away from the clinic. This protocol could be used to deliver tDCS paired with training or rehabilitation activities remotely to service members and veterans.

Steyvers, M., Schafer, R.J. Inferring latent learning factors in large-scale cognitive training data. Nat Hum Behav (2020). doi:10.1038/s41562-020-00935-3

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The flexibility to learn diverse tasks is a hallmark of human cognition. To improve our understanding of individual differences and dynamics of learning across tasks, we analyse the latent structure of learning trajectories from 36,297 individuals as they learned 51 different tasks on the Lumosity online cognitive training platform. Through a data-driven modelling approach using probabilistic dimensionality reduction, we investigate covariation across learning trajectories with few assumptions about learning curve form or relationships between tasks. Modelling results show substantial covariation across tasks, such that an entirely unobserved learning trajectory can be predicted by observing trajectories on other tasks. The latent learning factors from the model include a general ability factor that is expressed mostly at later stages of practice and additional task-specific factors that carry information capable of accounting for manually defined task features and task domains such as attention, spatial processing, language and math.

Thomas, K.N., & Bardeen, J.R. (2020). The buffering effect of attentional control on the relationship between cognitive fusion and anxiety. Behaviour Research and Therapy, 132, 103653. doi:10.1016/j.brat.2020.103653

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Cognitive fusion has been identified as a risk factor for anxiety. Evidence suggests that those with better attentional control may be able to flexibly shift attention from an internal to external focus, thus reducing contact with negative self-referent thoughts. As such, attentional control was examined as a moderator of the relation between cognitive fusion and anxiety in this two-part study. Adult participants (N = 597) completed self-report measures in Study 1. In Study 2, adult student participants (N = 173) completed self-report measures of cognitive fusion and anxiety, as well as behavioral measures that assessed three specific attentional control processes (i.e., inhibition, shifting, working memory updating). As predicted, attentional control moderated the relation between cognitive fusion and anxiety such that the strength of the relation decreased as attentional control increased. The results of Study 2 suggest that inhibitory ability is the attentional control process that accounts for this effect. Taken together, results suggest the possibility that attentional control (especially inhibitory ability) may be a protective factor against the development of anxiety among those with higher levels of cognitive fusion. The use of experimental and longitudinal study designs will be an important next step in this line of research to further clarify the nature of relations among cognitive fusion, attentional control, and anxiety. Results from an exploratory analysis, in which depressive symptoms served as the outcome variable, will also be discussed.

Towe, S.L., Hartsock, J.T., Xu, Y. et al. Web-Based Cognitive Training to Improve Working Memory in Persons with Co-Occurring HIV Infection and Cocaine Use Disorder: Outcomes from a Randomized Controlled Trial. AIDS Behav (2020). doi:10.1007/s10461-020-02993-0

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Neurocognitive impairment (NCI) remains a persistent complication of HIV disease that nearly half of persons with HIV experience, and rates are even higher in persons who use substances such as cocaine. Cognitive training is a promising intervention for HIV-associated NCI. In this randomized controlled trial, we examined the feasibility and effectiveness of a web-based cognitive training program to improve working memory in a sample of 58 persons with HIV and cocaine use disorder. Participants were randomly assigned to either the experimental working memory training arm or the attention control training arm and completed up to 48 daily sessions over 10 weeks. Overall, treatment completion (74%) and retention rates (97%) were high, and participant feedback indicated the intervention was acceptable. Our results show that the intervention successfully reduced working memory deficits in the experimental arm relative to the control arm. Our findings support both the feasibility and effectiveness of cognitive training in this population.

Yang, L., Gallant, S. N., Wilkins, L. K., & Dyson, B. (2020). Cognitive and Psychosocial Outcomes of Self-Guided Executive Function Training and Low-intensity Aerobic Exercise in Healthy Older Adults. Frontiers in Aging Neuroscience, 12, 334. doi:10.3389/fnagi.2020.576744

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Objectives: Prior work has demonstrated that executive function training or physical exercise can improve older adults’ cognition. The current study takes an exploratory approach to compare the feasibility and efficacy of online executive function training and low-intensity aerobic exercise for improving cognitive and psychosocial functioning in healthy older adults.

Method: Following a standard pretest-training-posttest protocol, 40 older adults (aged 65 and above) were randomly assigned to an executive function or a physical training group. A battery of cognitive and psychosocial outcome measures were administered before and after training. During the 10 weeks of self-guided training at home (25–30 min/day, 4 days/week), the executive function training group practiced a set of adaptive online executive function tasks designed by Lumos Labs, whereas the physical training group completed an adaptive Digital Video Disc (DVD)-based low-intensity aerobic exercise program.

Results: Training transfer effects were limited. Relative to low-intensity aerobic exercise, executive function training yielded cognitive improvement on the 64-card Wisconsin Card Sorting Task (WCST-64), a general executive function measure. Depression and stress levels dropped following both training programs, but this could be driven by decreased stress or excitement in performing the tasks over time.

Discussion: The results revealed limited cognitive benefits of the online executive function training program, specifically to a near transfer test of general executive control. Importantly, the current study supports the feasibility of home-based self-guided executive function and low-intensity physical training with healthy older adults.

2019

Lassonde, K. A., & Osborn, R. M. (2019). Lumosity does not best classroom memory improvement strategies. Scholarship of Teaching and Learning in Psychology, 5(1), 1. doi:10.1037/stl0000125

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The general population and students alike often rely on technology, rather than ability to remember. Yet, there are many situations when college students could benefit from basic memory improvement strategies. Students in two separate sections of a Human Memory course completed 3 memory assessments: One at the beginning of the course, a second at the midterm, and a third during the final week of the course. Each assessment contained well-known memory tasks. Throughout the course, both sections engaged in strategies to improve their memory. Additionally, one section participated in the online cognitive training program Lumosity for 12 weeks. The 2 sections’ scores on memory assessments were compared at each of the 3 assessment times during the course. Students’ performance improved during assessments for the following tasks in both course sections: word formation, F (2, 132) = 5.97, p = .003, MSe = 31.40, ηp² = .08, word recall, F (2, 134) = 19.20, p < .001, MSe = 78.71, ηp² = .22., and operation-span math 2, F (2, 134) = 17.86, p = .000, MSe = 32.98, ηp² = .21. Following each assessment, students self-reported on memory change. Students perceived the course work as having the biggest impact on their memory improvement. They also reported enjoying Lumosity and that they would recommend it to a friend or family member. Implications of how these findings can inform a more general debate on memory improvement strategies and perceptions will be discussed.

Richards, A., Kanady, J.C., Huie, J.R., Straus, L.D., Inslicht, S. S., Levihn-Coon, A., ... Neylan, T.C. (2019). Work by day and sleep by night, do not sleep too little or too much: Effects of sleep duration, time of day and circadian synchrony on flanker-task performance in internet brain-game users from teens to advanced age. Journal of Sleep Research, April, 1–11. doi:10.1111/jsr.12919

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Research elucidating the effects of sleep and circadian rhythm on cognitive performance is advancing, yet many important questions remain. Using flanker‐task performance scores from a large internet sample (N = 48,881) with repeated measures of cognitive performance and linked prior‐night self‐reported sleep duration, we analysed the relationship between sleep duration, time of day of task performance, and chronotype synchrony with performance in participants aged 15–80 years. Results indicate a performance peak at 7 hr habitual sleep duration, and point to a variable effect of deviation from habitual sleep duration depending on users’ habitual sleep duration and age. Time‐of‐day effects were notable for a steady decline in performance up until 01:00 hours–02:00 hours for the group as a whole, which was accounted for by nighttime deterioration on trials requiring inhibitory executive functioning, particularly in older subjects. Analyses did not demonstrate an advantage for playing in synchrony with self‐identified chronotype. Results strengthen findings indicating an inverted U‐shaped relationship between sleep duration and cognitive performance across a broad spectrum of age groups. These findings underscore the importance of daytime task performance for tasks requiring inhibitory function, especially in elderly people. Findings highlight the utility of large‐scale internet data in contributing to sleep and circadian science.

Ruiz-Marquez, E., Prieto, A., Mayas, J., Toril, P., Reales, J.M., & Ballesteros, S. (2019). Effects of Nonaction Videogames on Attention and Memory in Young Adults. Games for Health Journal, 8(6), 414–422. doi:10.1089/g4h.2019.0004

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Objective: In this intervention study, we investigated the benefits of nonaction videogames on measures of selective attention and visuospatial working memory (WM) in young adults.

Materials and Methods: Forty-eight young adults were randomly assigned to the experimental group or to the active control group. The experimental group played 10 nonaction adaptive videogames selected from Lumosity, whereas the active control group played two nonadaptive simulation-strategy games (SimCity and The Sims). Participants in both groups completed 15 training sessions of 30 minutes each. The training was conducted in small groups. All the participants were tested individually before and after training to assess possible transfer effects to selective attention, using a Cross-modal Oddball task, inhibition with the Stroop task, and visuospatial WM enhancements with the Corsi blocks task.

Results: Participants improved videogame performance across the training sessions. The results of the transfer tasks show that the two groups benefited similarly from game training. They were less distracted and improved visuospatial WM.

Conclusion: Overall, there was no significant interaction between group (group trained with adaptive nonaction videogames and the active control group that played simulation games) and session (pre- and post-assessment). As we did not have a passive nonintervention control group, we cannot conclude that adaptive nonaction videogames had a positive effect, because some external factors might account for the pre- and post-test improvements observed in both groups.

Steyvers, M., & Benjamin, A. S. (2019). The joint contribution of participation and performance to learning functions: Exploring the effects of age in large-scale data sets. Behavior Research Methods, 51(4), 1531–1543. doi:10.3758/s13428-018-1128-2

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Large-scale data sets from online training and game platforms offer the opportunity for more extensive and more precise investigations of human learning than is typically achievable in the laboratory. However, because people make their own choices about participation, any investigation into learning using these data sets must simultaneously model performance–that is, the learning function–and participation. Using a data set of 54 million gameplays from the online brain training site Lumosity, we show that learning functions of participants are systematically biased by participation policies that vary with age. Older adults who are poorer performers are more likely to drop out than older adults who perform well. Younger adults show no such effect. Using this knowledge, we can extrapolate group learning functions that correct for these age-related differences in dropout. Learning in the real world involves many choices. We decide when to study, how to study, and when to stop studying and turn to something else. In the history of research on learning, particularly within psychology, the vast majority of scientific approaches attempt to control for these and other sources of variation in self-control, with the hope that what will emerge is an “uncontaminated” view of learning and memory (Koriat & Goldsmith, 1994; Benjamin, 2007; Nelson & Narens, 1994) Whatever the merits of this approach, it is unsatisfactory for large ecologically situated data sets in which learners come and go at their leisure. Understanding learning and memory in tasks in which learners exert considerable control over aspects of their learning requires an explicit consideration of metacognitive factors that determine participation and influence performance. Here we present learning data from the online “brain-training” platform Lumosity. Lumosity provides a number of different games for users that are intended to tap memory, attention, flexibility, speeded processing, and problem solving. Many of these games are based on well-worn tasks from cognitive psychology. Millions of people play these games, providing a very rich platform on which to study learning (Donner & Hardy, 2015). However, unlike lab studies, where individuals follow a strict regime and can be coerced to provide a sufficient number of data points to fit functions to that individual’s performance, participants in online platforms decide when to play, how often to play, and when to quit. A joint consideration of participation and performance allows us to use these large-scale data sets to evaluate theories of learning and of metacognition. Generally, the use of online platforms for investigating skill learning has grown in the past few years (Donner & Hardy, 2015; Huang et al., 2017; Stafford & Dewar, 2014), and is part of a welcome new trend of using naturally occurring large-scale data sets to develop and test theories of cognition (Goldstone & Lupyan, 2016; Griffiths, 2015). The lesson we draw here is that any model of skill learning from an uncontrolled source like an online learning platform must jointly deal with questions of performance and of participation. When individuals drop out of the task randomly, like they often do in the lab (say, due to computer problems), then dropout behavior increases variability and the potential for heteroskedasticity at more distant points in the learning function. However, when individuals drop out for reasons that are related to their current or future performance, learning functions are directly biased. Averaging across individuals has long been known to influence the shape of learning functions (Estes, 1956), but the effects of voluntary participation on group learning functions has not, to our knowledge, previously been considered. This is not a statistical problem: only a model of the process by which individuals choose to stay or go can debias such effects. In this paper, we present a theoretical and empirical investigation of the effects of voluntary participation and withdrawal on aggregated learning functions. We start with an empirical analysis of learning functions for individuals and for groups that differ in age. We show that individuals who drop out earlier lie on a different learning trajectory than those who continue, indicating that group learning functions will be biased by differential participation. Specifically, older adults who withdraw early exhibit a slower rate of improvement than older adults who continue with the task. Younger adults do not reveal this systematic pattern of withdrawal. In addition, we apply models of learning to individual performance functions and estimate the trajectory of those functions for a subset of users of different ages. Using these individual fits, we show that the slopes of the learning functions are typically shallower for individuals who drop out early. We then use the fits to extrapolate performance for those who withdrew to trials that they never actually completed. In doing so, we show that age-related group learning functions corrected for differential withdrawal are markedly different than the uncorrected functions. As a starting point for considering the effect of systematic dropout on learning curves, Fig. 1 shows simulated data under a number of scenarios. The left panel shows simulated learning curves that vary in learning rate and asymptote. The red curve shows the aggregate learning function. The middle panel uses the same learning curves and simulates the effect of dropout when individuals drop out for reasons unrelated to performance. In this case, the aggregate learning curve is unbiased by the dropout. In the right panel, the probability of dropping out is negatively related to (latent) asymptotic performance. Here it can be seen that the aggregate learning function is considerably biased from the original. One of the advantages of using large-scale naturalistic data sets for cognitive research is the diversity of users such platforms attract. Here we use the large age range of participants to examine the learning curves and dropout rates of users across the lifespan. Older users might have different motivations for using Lumosity than younger users, and those motivations might influence participation policies. Older adults may be motivated to combat cognitive decline and thus be more inclined to stick with tasks that they find difficult. Alternatively, they may be more sensitive to the stereotype threat posed by poor performance and thus be quick to quit tasks that they perform poorly on. Age effects on memory and attention tasks are well documented (Park & Schwarz, 2000) but can only be fairly interpreted in naturalistic data sets by seriously considering participation policies.

Steyvers, M., Hawkins, G.E., Karayanidis, F., & Brown, S.D. (2019). A large-scale analysis of task switching practice effects across the lifespan. Proceedings of the National Academy of Sciences, 116(36), 17735-17740. doi:10.1073/pnas.1906788116

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An important feature of human cognition is the ability to flexibly and efficiently adapt behavior in response to continuously changing contextual demands. We leverage a large-scale dataset from Lumosity, an online cognitive-training platform, to investigate how cognitive processes involved in cued switching between tasks are affected by level of task practice across the adult lifespan. We develop a computational account of task switching that specifies the temporal dynamics of activating task-relevant representations and inhibiting task-irrelevant representations and how they vary with extended task practice across a number of age groups. Practice modulates the level of activation of the task-relevant representation and improves the rate at which this information becomes available, but has little effect on the task-irrelevant representation. While long-term practice improves performance across all age groups, it has a greater effect on older adults. Indeed, extensive task practice can make older individuals functionally similar to less-practiced younger individuals, especially for cognitive measures that focus on the rate at which task-relevant information becomes available.

Woo, Y.J., Kanellopoulos, A.K., Hemati, P., Kirschen, J., Nebel, R. A., Wang, T., ... Abrahams, B.S. (2019). Domain-Specific Cognitive Impairments in Humans and Flies With Reduced CYFIP1 Dosage. Biological Psychiatry, 86(4), 306–314. doi:10.1016/j.biopsych.2019.04.008

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Background: Deletions encompassing a four-gene region on chromosome 15 (BP1-BP2 at 15q11.2), seen at a population frequency of 1 in 500, are associated with increased risk for schizophrenia, epilepsy, and other common neurodevelopmental disorders. However, little is known in terms of how these common deletions impact cognition.
Methods: We used a Web-based tool to characterize cognitive function in a novel cohort of adult carriers and their noncarrier family members. Results from 31 carrier and 38 noncarrier parents from 40 families were compared with control data from 6530 individuals who self-registered on the Lumosity platform and opted in to participate in research. We then examined aspects of sensory and cognitive function in flies harboring a mutation in Cyfip, the homologue of one of the genes within the deletion. For the fly studies, 10 or more groups of 50 individuals per genotype were included.
Results: Our human studies revealed profound deficits in grammatical reasoning, arithmetic reasoning, and working memory in BP1-BP2 deletion carriers. No such deficits were observed in noncarrier spouses. Our fly studies revealed deficits in associative and nonassociative learning despite intact sensory perception.
Conclusions: Our results provide new insights into outcomes associated with BP1-BP2 deletions and call for a discussion on how to appropriately communicate these findings to unaffected carriers. Findings also highlight the utility of an online tool in characterizing cognitive function in a geographically distributed population.

2018

Bainbridge, K., & Mayer, R. E. (2018). Shining the light of research on Lumosity. Journal of Cognitive Enhancement, 2(1), 43-62.

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Lumosity is a subscription-based suite of online brain-training games, intended to improve cognitive skills. Due to an influx of products designed to train cognition through games such as Lumosity, it is important to determine their effectiveness for the sake of consumers and for the potential implications of any training effects for theories of transfer of cognitive skills. Two training experiments were conducted using the Lumosity platform. Participants were divided into three groups: those who trained with five attention games in Lumosity (attention group), those who trained with five flexibility games in Lumosity (flexibility group), and an inactive control group. Participants were assessed on accuracy and response time for two cognitive tests of attention (useful field of view and change detection) and two cognitive tests of flexibility (Wisconsin card sort and Stroop) both before and after a training period. In experiment 1, the training period was 3 h spread over four sessions. In experiment 2, the training period was 15 to 20 h spread over an average of 73 sessions. The trained groups did not show significantly greater pretest-to-posttest gains than the control group on any measures in either experiment, except in experiment 2 where the flexibility group significantly outperformed the other two groups on Stroop response time and UFOV reaction time. A practical implication concerns the lack of strong evidence for the effectiveness of brain-training games to improve cognitive skills. A theoretical implication concerns the domain specificity of cognitive skill learning from brain training games.

Bell, C. F., Warrick, M. M., Gallagher, K. C., & Baregamian, N. (2018). Neurocognitive performance profile postparathyroidectomy: a pilot study of computerized assessment. Surgery (United States), 163(2), 457–462. doi:10.1016/j.surg.2017.09.001

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Abstract

Background: Neurocognitive symptoms attributable to primary hyperparathyroidism are important diagnostic criteria, yet the basic characterization and assessment of neurocognitive deficits in primary hyperparathyroidism are not defined fully.
Methods: In this prospective pilot study, patients with unequivocal biochemical diagnosis of primary hyperparathyroidism were evaluated for neurocognitive performance preoperatively and postparathyroidectomy (2 weeks, 6 months) using a battery of computerized modular tests designed by LUMOSITY. The individual test scores and aggregate scores representing a subject's total neurocognitive performance profile were calculated. Statistical comparisons between groups were performed using univariate analysis and repeated measures of analysis of variance.
Results: In the study, 34 participants were assessed preoperatively; 18 completed all 3 assessments, 2 completed pretest and 6-month assessments, and 30 completed preoperative and 2-week postparathyroidectomy assessments. Primary hyperparathyroidism patients demonstrated significant deficits in memory, attention, mental flexibility, and speed of processing when compared with controls. Total neurocognitive performance profile score was significantly lower at the preoperative (P = .0001) and 2-week postparathyroidectomy (P = .0004) time points when compared with controls; this difference was bridged by 6 months postparathyroidectomy.
Conclusion: Computerized neurocognitive performance profile assessment validated the neurocognitive benefits of parathyroidectomy. Additional study is needed to determine if this novel method provides long-term, objective, quantifiable, and accessible neurocognitive performance profile assessment in primary hyperparathyroidism patients and can serve as a valuable diagnostic and prognostic tool.

Ben-Zion, Z., Fine, N.B., Keynan, N.J., Admon, R., Green, N., Halevi, M., ... Shalev, A.Y. (2018). Cognitive flexibility predicts PTSD symptoms: Observational and interventional studies. Frontiers in Psychiatry, 9(OCT), 1–9. doi:10.3389/fpsyt.2018.00477

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Introduction: Post-Traumatic Stress Disorder (PTSD) is a prevalent, severe and tenacious psychopathological consequence of traumatic events. Neurobehavioral mechanisms underlying PTSD pathogenesis have been identified, and may serve as risk-resilience factors during the early aftermath of trauma exposure. Longitudinally documenting the neurobehavioral dimensions of early responses to trauma may help characterize survivors at risk and inform mechanism-based interventions. We present two independent longitudinal studies that repeatedly probed clinical symptoms and neurocognitive domains in recent trauma survivors. We hypothesized that better neurocognitive functioning shortly after trauma will be associated with less severe PTSD symptoms a year later, and that an early neurocognitive intervention will improve cognitive functioning and reduce PTSD symptoms.
Methods: Participants in both studies were adult survivors of traumatic events admitted to two general hospitals’ emergency departments (EDs) in Israel. The studies used identical clinical and neurocognitive tools, which included assessment of PTSD symptoms and diagnosis, and a battery of neurocognitive tests. The first study evaluated 181 trauma-exposed individuals one-, six-, and 14 months following trauma exposure. The second study evaluated 97 trauma survivors 1 month after trauma exposure, randomly allocated to 30 days of web-based neurocognitive intervention (n = 50) or control tasks (n = 47), and re-evaluated all subjects three- and 6 months after trauma exposure.
Results: In the first study, individuals with better cognitive flexibility at 1 month post-trauma showed significantly less severe PTSD symptoms after 13 months (p = 0.002). In the second study, the neurocognitive training group showed more improvement in cognitive flexibility post-intervention (p = 0.019), and lower PTSD symptoms 6 months post-trauma (p = 0.017), compared with controls. Intervention- induced improvement in cognitive flexibility positively correlated with clinical improvement (p = 0.002).
Discussion: Cognitive flexibility, shortly after trauma exposure, emerged as a significant predictor of PTSD symptom severity. It was also ameliorated by a neurocognitive intervention and associated with a better treatment outcome. These findings support further research into the implementation of mechanism-driven neurocognitive preventive interventions for PTSD.

Charvet, L., Shaw, M., Dobbs, B., Frontario, A., Sherman, K., Bikson, M., ... Kasschau, M. (2018). Remotely Supervised Transcranial Direct Current Stimulation Increases the Benefit of At-Home Cognitive Training in Multiple Sclerosis. Neuromodulation, 21(4), 383–389. doi:10.1111/ner.12583

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Abstract

Objective: To explore the efficacy of remotely-supervised transcranial direct current stimulation (RS-tDCS) paired with cognitive training (CT) exercise in participants with multiple sclerosis (MS).
Methods: In a feasibility study of RS-tDCS in MS, participants completed ten sessions of tDCS paired with CT (1.5 mA × 20 min, dorsolateral prefrontal cortex montage). RS-tDCS participants were compared to a control group of adults with MS who underwent ten 20-min CT sessions through the same remotely supervised procedures. Cognitive outcomes were tested by composite scores measuring change in performance on standard tests (Brief International Cognitive Assessment in MS or BICAMS), basic attention (ANT-I Orienting and Attention Networks, Cogstate Detection), complex attention (ANT-I Executive Network, Cogstate Identification and One-Back), and intra-individual response variability (ANT-I and Cogstate identification; sensitive markers of disease status).
Results: After ten sessions, the tDCS group (n = 25) compared to the CT only group (n = 20) had significantly greater improvement in complex attention (p = 0.01) and response variability (p = 0.01) composites. The groups did not differ in measures of basic attention (p =0.95) or standard cognitive measures (p = 0.99).
Conclusions: These initial findings indicate benefit for RS-tDCS paired with CT in MS. Exploratory analyses indicate that the earliest tDCS cognitive benefit is seen in complex attention and response variability. Telerehabilitation using RS-tDCS combined with CT may lead to improved outcomes in MS.

Corti, C., Poggi, G., Romaniello, R., Strazzer, S., Urgesi, C., Borgatti, R., & Bardoni, A. (2018). Feasibility of a home-based computerized cognitive training for pediatric patients with congenital or acquired brain damage: An explorative study. PLoS ONE, 13(6), 1–16. doi:10.1371/journal.pone.0199001

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Abstract

Objectives: Pediatric brain damage is associated with various cognitive deficits. Cognitive rehabilitation may prevent and reduce cognitive impairment. In recent years, home-based computerized cognitive training (CCT) has been introduced in clinical practice to increase treatment opportunities for patients (telerehabilitation). However, limited research has been conducted thus far on investigating the effects of remote CCT for the juvenile population in contexts other than English-speaking countries. The aim of the present study was to investigate the feasibility of a home-based CCT in a group of Italian adolescents with brain damage. A commercially available CCT (Lumosity) developed in the English language was used due to the lack of telerehabilitation programs in the Italian language that allow stimulation of multiple cognitive domains and, at the same time, remote automatic collection of data. Thus, this investigation provides information on the possibility of introducing CCT programs available in foreign languages in countries with limited investment in the telerehabilitation field.
Methods: 32 adolescents aged 11–16 with a diagnosis of congenital or acquired (either traumatic or non-traumatic) brain damage participated in the study. They received 40 training sessions (5 days/week for 8 weeks). Before starting the training program, they received face-to-face demonstration of training exercises and written instructions in their mother tongue. The feasibility of both training and study design and procedures was assessed through 9 criteria taken from extant literature.
Results: All 9 feasibility criteria were met. 31 out of the 32 participants demonstrated adherence to the training program. 94.2% of training sessions were completed in the recommended timeframe. No significant technical issue was found.
Conclusions: Telerehabilitation seems to be a feasible practice for adolescents with brain damage. A training program developed in a foreign language can be used to counter the unavailability of programs in patients’ mother tongue.

McAdams-DeMarco, M.A., Konel, J., Warsame, F., Ying, H., Fernández, M. G., Carlson, M. C., ... Segev, D. L. (2018). Intradialytic Cognitive and Exercise Training May Preserve Cognitive Function. Kidney International Reports, 3(1), 81–88. doi:10.1016/j.ekir.2017.08.006

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Introduction: Cognitive decline is common and increases mortality risk in hemodialysis patients. Intradialytic interventions like cognitive training (CT) and exercise training (ET) may preserve cognitive function.
Methods: We conducted a pilot randomized controlled trial of 20 hemodialysis patients to study the impact of 3 months of intradialytic CT (tablet-based brain games) (n = 7), ET (foot peddlers) (n = 6), or standard of care (SC) (n = 7) on cognitive function. Global cognitive function was measured by the Modified Mini Mental Status Exam (3MS), psychomotor speed was measured by Trail Making Tests A and B (TMTA and TMTB), and executive function was assessed by subtracting (TMTB − TMTA). Lower 3MS scores and slower TMTA and TMTB times reflected worse cognitive function. P values for differences were generated using analysis of variance, and 95% confidence intervals (CIs) and P values were generated from linear regression.
Results: Patients with SC experienced a decrease in psychomotor speed and executive function by 3 months (TMTA: 15 seconds; P = 0.055; TMTB: 47.4 seconds; P = 0.006; TMTB − TMTA; 31.7 seconds; P = 0.052); this decline was not seen among those with CT or ET (all P > 0.05). Compared with SC, the difference in the mean change in 3MS score was −3.29 points (95% CI: −11.70 to 5.12; P = 0.42) for CT and 4.48 points (95% CI: −4.27 to 13.22; P = 0.30) for ET. Compared with SC, the difference in mean change for TMTA was −15.13 seconds (95% CI: −37.64 to 7.39; P = 0.17) for CT and −17.48 seconds (95% CI: −41.18 to 6.22; P = 0.14) for ET, for TMTB, the difference was −46.72 seconds (95% CI: −91.12 to −2.31; P = 0.04) for CT and −56.21 seconds (95% CI: −105.86 to −6.56; P = 0.03) for ET, and for TMTB – TMTA, the difference was −30.88 seconds (95% CI: −76.05 to 14.28; P = 0.16) for CT and −34.93 seconds (95% CI: −85.43 to 15.56; P = 0.16) for ET.
Conclusion: Preliminary findings of our pilot study suggested that cognitive decline in psychomotor speed and executive function is possibly prevented by intradialytic CT and ET. These preliminary pilot findings should be replicated.

Weiner, M. W., Nosheny, R., Camacho, M., Truran‐Sacrey, D., Mackin, R. S., Flenniken, D., ... & Veitch, D. (2018). The Brain Health Registry: an internet‐based platform for recruitment, assessment, and longitudinal monitoring of participants for neuroscience studies. Alzheimer's & Dementia, 14(8), 1063-1076. doi:10.1016/j.jalz.2018.02.021

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Abstract

Introduction: Recruitment, assessment, and longitudinal monitoring of participants for neuroscience studies and clinical trials limit the development of new treatments. Widespread Internet use allows data capture from participants in an unsupervised setting. The Brain Health Registry, a website and online registry, collects data from participants and their study partners.

Methods: The Brain Health Registry obtains self and study partner report questionnaires and neuropsychological data, including the Cogstate Brief Battery, Lumos Labs Neurocognitive Performance Test, and MemTrax Memory Test. Participants provide informed consent before participation.

Results: Baseline and longitudinal data were obtained from nearly 57,000 and 28,000 participants, respectively. Over 18,800 participants were referred to, and nearly 1800 were enrolled in, clinical Alzheimer's disease and aging studies, including five observational studies and seven intervention trials.

Discussion: Online assessments of participants and study partners provide useful information at relatively low cost for neuroscience studies and clinical trials and may ultimately be used in routine clinical practice.

Withiel, T.D., Sharp, V.L., Wong, D., Ponsford, J.L., Warren, N., & Stolwyk, R. J. (2020). Understanding the experience of compensatory and restorative memory rehabilitation: A qualitative study of stroke survivors. Neuropsychological Rehabilitation, 30(3), 503–522. doi:10.1080/09602011.2018.1479275

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Memory impairment is common following stroke. Memory skills groups (MSGs) utilising compensatory strategies and computerised cognitive training (CCT) are two rehabilitation approaches available to improve memory function; however, there is no consensus as to which is more effective following stroke. This study aimed to explore and contrast the qualitative experiences of 20 stroke survivors (Mage = 61.90, SD = 10.48, range: 34–77 years) who received six weeks’ training in MSG (manualised memory skills group, n = 10) or individual-CCT (LumosityTM, n = 10). Using semi-structured interviews, data were collected and analysed thematically, adopting a critical realist approach. Six themes were identified: (1) Facilitators and barriers to intervention engagement, (2) Improving knowledge and understanding, (3) Connecting with others, (4) Perception of the intervention, (5) Impact on everyday memory and (6) Impact on emotions and sense of purpose. Encouragingly, most participants valued and enjoyed participating in the memory interventions, irrespective of rehabilitation approach. MSG participants reported learning and sharing with similar others as important to the experience and described everyday memory improvements. CCT participants described enjoyment of its game-like nature, yet reported frustration associated with game-specific characteristics, and did not report everyday memory improvements.

Withiel, T.D., Wong, D., Ponsford, J.L., Cadilhac, D.A., & Stolwyk, R. J. (2020). Feasibility and effectiveness of computerised cognitive training for memory dysfunction following stroke: A series of single case studies. Neuropsychological Rehabilitation, 30(5), 829–852. doi:10.1080/09602011.2018.1503083

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Computerised cognitive training (CCT) approaches to memory rehabilitation represent an attractive alternative to traditional approaches; however, there is limited empirical evidence to support their use. An AB with follow up single case design was repeated across five participants to explore the feasibility and effectiveness of CCT on subjective memory in patients with stroke. Target behaviour was subjective everyday and prospective memory failures which were assessed weekly. Following baseline (three weeks), participants completed six weeks of LumosityTM training in their homes. Data were analysed visually and statistically. The frequency of prospective memory failures decreased during intervention for one participant, while the frequency of prospective and everyday memory failures decreased significantly during the follow up period for another participant. Yet, significantly more everyday and prospective memory failures were reported following training by one study participant. No significant change in subjective memory ratings was found for remaining participants. Regarding secondary outcomes, meaningful changes on objective measures of memory were not observed, despite considerable inter-individual variability. Three participants reported improvement in individualised memory goals, while two participants described a decline. Overall, LumosityTM training appears feasible; however, no consistent evidence to support effectiveness of this CCT on subjective or objective memory was found.

2017

Ballesteros, S., Mayas, J., Ruiz-Marquez, E., Prieto, A., Toril, P., Ponce de Leon, L., ... Reales Avilés, J. M. (2017). Effects of Video Game Training on Behavioral and Electrophysiological Measures of Attention and Memory: Protocol for a Randomized Controlled Trial. JMIR Research Protocols, 6(1), e8. doi:10.2196/resprot.6570

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Abstract

Background: Neuroplasticity-based approaches seem to offer promising ways of maintaining cognitive health in older adults and postponing the onset of cognitive decline symptoms. Although previous research suggests that training can produce transfer effects, this study was designed to overcome some limitations of previous studies by incorporating an active control group and the assessment of training expectations.
Objective: The main objectives of this study are (1) to evaluate the effects of a randomized computer-based intervention consisting of training older adults with nonaction video games on brain and cognitive functions that decline with age, including attention and spatial working memory, using behavioral measures and electrophysiological recordings (event-related potentials [ERPs]) just after training and after a 6-month no-contact period; (2) to explore whether motivation, engagement, or expectations might account for possible training-related improvements; and (3) to examine whether inflammatory mechanisms assessed with noninvasive measurement of C-reactive protein in saliva impair cognitive training-induced effects. A better understanding of these mechanisms could elucidate pathways that could be targeted in the future by either behavioral or neuropsychological interventions.
Methods: A single-blinded randomized controlled trial with an experimental group and an active control group, pretest, posttest, and 6-month follow-up repeated measures design is used in this study. A total of 75 cognitively healthy older adults were randomly distributed into experimental and active control groups. Participants in the experimental group received 16 1-hour training sessions with cognitive nonaction video games selected from Lumosity, a commercial brain training package. The active control group received the same number of training sessions with The Sims and SimCity, a simulation strategy game.
Results: We have recruited participants, have conducted the training protocol and pretest assessments, and are currently conducting posttest evaluations. The study will conclude in the first semester of 2017. Data analysis will take place during 2017. The primary outcome is transfer of benefit from training to attention and working memory functions and the neural mechanisms underlying possible cognitive improvements.
Conclusions: We expect that mental stimulation with video games will improve attention and memory both at the behavioral level and in ERP components promoting brain and mental health and ext

Bennike, I.H., Wieghorst, A. & Kirk, U. Online-based Mindfulness Training Reduces Behavioral Markers of Mind Wandering. J Cogn Enhanc 1, 172–181 (2017). doi:10.1007/s41465-017-0020-9

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It is estimated that people spend almost half their waking hours lost in stimulus-independent thought, or mind wandering, which in turn has been shown to negatively impact well-being. This has sparked a rise in the number of cognitive training platforms that aim to boost executive functioning, yet it is unclear whether mind wandering can be reduced through online training. The current study aimed to investigate whether behavioral markers of mind wandering can be reduced through two short-term online-based interventions: mindfulness meditation and brain training. Using a randomized controlled design, we assigned one group of participants to 30 days of mindfulness training (n = 54) and another to 30 days of brain training (n = 41). Mind wandering and dispositional mindfulness were assessed pre- and post-intervention via the Sustained Attention to Response Task (SART) and the Mindful Attention to Awareness Scale (MAAS), respectively. We found significant reductions in mind wandering and significant increases in dispositional mindfulness in the mindfulness training group but not the brain training group. A lack of any significant change in the brain training group may be driven by methodological limitations such as self-report bias. These results indicate that short online mindfulness-based interventions may be effective in reducing mind wandering.

Clark, C. M., Lawlor-Savage, L., & Goghari, V. M. (2017). Working memory training in healthy young adults: Support for the null from a randomized comparison to active and passive control groups. PLoS ONE, 12(5), 1–25. doi:10.1371/journal.pone.0177707

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Training of working memory as a method of increasing working memory capacity and fluid intelligence has received much attention in recent years. This burgeoning field remains highly controversial with empirically-backed disagreements at all levels of evidence, including individual studies, systematic reviews, and even meta-analyses. The current study investigated the effect of a randomized six week online working memory intervention on untrained cognitive abilities in a community-recruited sample of healthy young adults, in relation to both a processing speed training active control condition, as well as a no-contact control condition. Results of traditional null hypothesis significance testing, as well as Bayesian factor analyses, revealed support for the null hypothesis across all cognitive tests administered before and after training. Importantly, all three groups were similar at pre-training for a variety of individual variables purported to moderate transfer of training to fluid intelligence, including personality traits, motivation to train, and expectations of cognitive improvement from training. Because these results are consistent with experimental trials of equal or greater methodological rigor, we suggest that future research re-focus on: 1) other promising interventions known to increase memory performance in healthy young adults, and; 2) examining sub-populations or alternative populations in which working memory training may be efficacious.

Guerra-Carrillo, B., Katovich, K., & Bunge, S. A. (2017). Does higher education hone cognitive functioning and learning efficacy? Findings from a large and diverse sample. PLoS ONE, 12(8), 1–17. doi:10.1371/journal.pone.0182276

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Attending school is a multifaceted experience. Students are not only exposed to new knowledge but are also immersed in a structured environment in which they need to respond flexibly in accordance with changing task goals, keep relevant information in mind, and constantly tackle novel problems. To quantify the cumulative effect of this experience, we examined retrospectively and prospectively, the relationships between educational attainment and both cognitive performance and learning. We analyzed data from 196,388 subscribers to an online cognitive training program. These subscribers, ages 15–60, had completed eight behavioral assessments of executive functioning and reasoning at least once. Controlling for multiple demographic and engagement variables, we found that higher levels of education predicted better performance across the full age range, and modulated performance in some cognitive domains more than others (e.g., reasoning vs. processing speed). Differences were moderate for Bachelor’s degree vs. High School (d = 0.51), and large between Ph.D. vs. Some High School (d = 0.80). Further, the ages of peak cognitive performance for each educational category closely followed the typical range of ages at graduation. This result is consistent with a cumulative effect of recent educational experiences, as well as a decrement in performance as completion of schooling becomes more distant. To begin to characterize the directionality of the relationship between educational attainment and cognitive performance, we conducted a prospective longitudinal analysis. For a subset of 69,202 subscribers who had completed 100 days of cognitive training, we tested whether the degree of novel learning was associated with their level of education. Higher educational attainment predicted bigger gains, but the differences were small (d = 0.04–0.37). Altogether, these results point to the long-lasting trace of an effect of prior cognitive challenges but suggest that new learning opportunities can reduce performance gaps related to one’s educational history.

Harris, A. W., Kosic, T., Xu, J., Walker, C., Gye, W., & Redoblado Hodge, A. (2017). Web-Based Cognitive Remediation Improves Supported Employment Outcomes in Severe Mental Illness: Randomized Controlled Trial. JMIR Mental Health, 4(3), e30. doi:10.2196/mental.6982

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Background: Finding work is a top priority for most people; however, this goal remains out of reach for the majority of individuals with a severe mental illness (SMI) who remain on benefits or are unemployed. Supported employment (SE) programs aimed at returning people with a severe mental illness to work are successful; however, they still leave a significant number of people with severe mental illness unemployed. Cognitive deficits are commonly found in SMI and are a powerful predictor of poor outcome. Fortunately, these deficits are amenable to treatment with cognitive remediation therapy (CRT) that significantly improves cognition in SMI. CRT combined with SE significantly increases the likelihood of individuals with severe mental illness obtaining and staying in work. However, the availability of CRT is limited in many settings.

Objective: The aim of this study was to examine whether Web-based CRT combined with a SE program can improve the rate return to work of people with severe mental illness.

Methods: A total of 86 people with severe mental illness (mean age 39.6 years; male: n=55) who were unemployed and who had joined a SE program were randomized to either a Web-based CRT program (CogRem) or an Internet-based control condition (WebInfo). Primary outcome measured was hours worked over 6 months post treatment.

Results: At 6 months, those participants randomized to CogRem had worked significantly more hours (P=.01) and had earned significantly more money (P=.03) than those participants randomized to the WebInfo control condition. No change was observed in cognition.

Conclusions: This study corroborates other work that has found a synergistic effect of combining CRT with a SE program and extends this to the use of Web-based CRT. The lack of any improvement in cognition obscures the mechanism by which an improved wage outcome for participants randomized to the active treatment was achieved. However, the study substantially lowers the barrier to the deployment of CRT with other psychosocial interventions for severe mental illness.

Richards, A., Inslicht, S. S., Metzler, T. J., Mohlenhoff, B. S., Rao, M. N., O’Donovan, A., & Neylan, T. C. (2017). Sleep and cognitive performance from teens to old age: More is not better. Sleep, 40(1). doi:10.1093/sleep/zsw029

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Objectives: To determine the interaction of age and habitual sleep duration in predicting cognitive performance in a large sample of participants aged 15 to 89 years.
Methods: This study is a cross-sectional analysis of performance data gathered between January 2012 and September 2013. First-time players (N = 512823) of three internet cognitive training games measuring processing speed, working memory, visuospatial memory, and arithmetic participated in the study.
Results: Performance was based on a measure of speed and accuracy for each game. The relationship between performance and self-reported habitual sleep duration was examined in the sample as a whole and across 10-year age groups starting at age 15 and ending at 75 and older. Performance peaked at 7 h of sleep duration for all three games in the sample as a whole, and the decrements in performance for sleep durations greater than 7 h were either comparable or greater in the youngest as compared to the oldest age groups.
Conclusions: These findings challenge the hypothesis that deteriorating cognitive performance with long sleep duration is driven by medical comorbidities associated with aging. Further, these data are consistent with an optimal dose model of sleep and suggest that the model for the homeostatic recovery of cognitive function as a function of sleep duration should incorporate a curvilinear decline with longer duration sleep, indicating that there may be a cost to increased sleep. Replication and further research is essential for clarifying the sleep duration–cognition relationship in youth and adults of all ages.

2016

Lathan, C., Wallace, A.S., Shewbridge, R., Ng, N., Morrison, G., & Resnick, H.E. (2016). Cognitive Health Assessment and Establishment of a Virtual Cohort of Dementia Caregivers. Dementia and Geriatric Cognitive Disorders Extra, 6(1), 98–107. doi:10.1159/000444390

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Background: Many factors impact caregivers' cognitive health and, by extension, their ability to provide care. This study examined the relationship between psychosocial factors and cognitive performance among dementia caregivers and established a virtual cohort of caregivers for future research.
Methods: Data on 527 caregivers were collected via a Web-based survey that assessed cognitive performance. Caregiver data were compared to corresponding data from 527 age-, race-, gender-, and education-matched controls from a normative database. Caregiver self-reported sleep, stress, health, and social support were also assessed.
Results: Caregivers performed significantly worse than controls on 3 of 5 cognitive subtests. Stress, sleep, perceived support, self-rated health, years of caregiving, race, and gender were significant predictors of cognitive performance.
Conclusion: In this sample of dementia caregivers, psychosocial factors interacted in complex ways to impact cognitive performance. Further investigation is needed to better understand how these factors affect cognitive performance among caregivers. This could be accomplished by the establishment of a virtual cohort that facilitates the development of digital tools to support the evaluation and management of caregiver needs in a manner that helps them remain effective in their caregiving roles.

Rattray, B., & Smee, D.J. (2016). The effect of high and low exercise intensity periods on a simple memory recognition test. Journal of Sport and Health Science, 5(3), 342–348. doi:10.1016/j.jshs.2015.01.005

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Purpose: The purpose of this study was to investigate the effect of variable intensities on a simple memory recognition task during exercise.
Methods: Twenty active participants took part in initial testing, a familiarization trial and then four 60 min cycling interventions in a randomized order. Interventions consisted of no exercise (control), constant exercise at 90% ventilatory threshold (constant) and 2 trials that initially mimicked the constant trial, but then included periods of high (∼90% VO2peak) and low intensities (∼50%VO2peak). Cardiorespiratory measures and capillary blood samples were taken throughout. A short tablet-based cognitive task was completed prior to and during (50 and 55 min into exercise) each intervention.
Results: The exercise conditions facilitated response time (p = 0.009), although the extent of this effect was not as strong in the variable exercise conditions (p = 0.011–0.089). High intensity exercise periods resulted in some cognitive regression back towards control trial performance. Elevations in cardiorespiratory measures and periods of hypocapnia could not explain changes in cognitive performance.
Conclusion: Changes in cognitive performance with variations in exercise intensity are likely to have implications for sport and occupational settings. The timing of cognitive tests to exercise intensity changes as well as use of short cognitive assessments will be important for future work.

Thompson, P.J., Conn, H., Baxendale, S.A., Donnachie, E., McGrath, K., Geraldi, C., & Duncan, J. S. (2016). Optimizing memory function in temporal lobe epilepsy. Seizure, 38, 68-74. doi:10.1016/j.seizure.2016.04.008

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PURPOSE: The study aimed to assess whether engagement in a memory training programme and performing internet brain training exercises improve memory function in people with temporal lobe epilepsy (TLE).
METHODS: Seventy-seven people with TLE, complaining of memory difficulties, completed the study. Participants ranged in age from 19 to 67 years and 40 had left TLE. Participants were randomised to one of four conditions; Group 1: traditional memory training, Group 2: Lumosity, an on-line cognitive training programme, Group 3: traditional memory training and Lumosity, and Group 4: no training. Memory efficiency and mood were assessed at baseline and three months later.
RESULTS: Group analyses indicated improved verbal recall after training (p<0.001) and improved subjective ratings (p<0.007). More participants reported a lessening of the memory burden (p<0.007) after training; differences were significant between Groups 1 and 3 compared to Group 4. Lumosity use was not associated with changes in the memory outcome measures but there was a relationship with depression ratings and the number of memory games played (p<0.01). Conventional memory training, IQ, and post-surgical status were associated with positive memory outcomes.
CONCLUSIONS: The study indicates traditional memory rehabilitation techniques can help reduce the burden of memory impairment in TLE. There was no evidence that Lumosity the on-line cognitive training programme had specific advantages. Positive change was not universal and larger studies will be required to explore factors associated with successful outcomes.

Toril, P., Reales, J.M., Mayas, J., & Ballesteros, S. (2016). Video game training enhances visuospatial working memory and episodic memory in older adults. Frontiers in human neuroscience, 10, 206. doi:10.3389/fnhum.2016.00206

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In this longitudinal intervention study with experimental and control groups, we investigated the effects of video game training on the visuospatial working memory (WM) and episodic memory of healthy older adults. Participants were 19 volunteer older adults, who received 15 1-h video game training sessions with a series of video games selected from a commercial package (Lumosity), and a control group of 20 healthy older adults. The results showed that the performance of the trainees improved significantly in all the practiced video games. Most importantly, we found significant enhancements after training in the trained group and no change in the control group in two computerized tasks designed to assess visuospatial WM, namely the Corsi blocks task and the Jigsaw puzzle task. The episodic memory and short-term memory of the trainees also improved. Gains in some WM and episodic memory tasks were maintained during a 3-month follow-up period. These results suggest that the aging brain still retains some degree of plasticity, and that video game training might be an effective intervention tool to improve WM and other cognitive functions in older adults.

Torous, J., Staples, P., Fenstermacher, E., Dean, J., & Keshavan, M. (2016). Barriers, benefits, and beliefs of brain training smartphone apps: an internet survey of younger US consumers. Frontiers in human neuroscience, 10, 180. doi:10.3389/fnhum.2016.00180

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Abstract

Background: While clinical evidence for the efficacy of brain training remains in question, numerous smartphone applications (apps) already offer brain training directly to consumers. Little is known about why consumers choose to download these apps, how they use them, and what benefits they perceive. Given the high rates of smartphone ownership in those with internet access and the younger demographics, we chose to approach this question first with a general population survey that would capture primarily this demographic.
Method: We conducted an online internet-based survey of the US population via mTurk regarding their use, experience, and perceptions of brain training apps. There were no exclusion criteria to partake although internet access was required. Respondents were paid 20 cents for completing each survey. The survey was offered for a 2-week period in September 2015.
Results: 3125 individuals completed the survey and over half of these were under age 30. Responses did not significantly vary by gender. The brain training app most frequently used was Lumosity. Belief that a brain-training app could help with thinking was strongly correlated with belief it could also help with attention, memory, and even mood. Beliefs of those who had never used brain-training apps were similar to those who had used them. Respondents felt that data security and lack of endorsement from a clinician were the two least important barriers to use.
Discussion: Results suggest a high level of interest in brain training apps among the US public, especially those in younger demographics. The stability of positive perception of these apps among app-naïve and app-exposed participants suggests an important role of user expectations in influencing use and experience of these apps. The low concern about data security and lack of clinician endorsement suggest apps are not being utilized in clinical settings. However, the public’s interest in the effectiveness of apps suggests a common theme with the scientific community’s concerns about direct to consumer brain training programs.

Wentink, M.M., Berger, M.A.M., de Kloet, A.J., Meesters, J., Band, G.P.H., Wolterbeek, R., ... & Vliet Vlieland, T.P.M. (2016). The effects of an 8-week computer-based brain training programme on cognitive functioning, QoL and self-efficacy after stroke. Neuropsychological rehabilitation, 26(5-6), 847-865. doi:10.1080/09602011.2016.1162175

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Abstract

Cognitive impairment after stroke has a direct impact on daily functioning and quality of life (QoL) of patients and is associated with higher mortality and healthcare costs. The aim of this study was to determine the effect of a computer-based brain training programme on cognitive functioning, QoL and self-efficacy compared to a control condition in stroke patients. Stroke patients with self-perceived cognitive impairment were randomly allocated to the intervention or control group. The intervention consisted of an 8-week brain training programme (Lumosity Inc.®). The control group received general information about the brain weekly. Assessments consisted of a set of neuropsychological tests and questionnaires. In addition, adherence with trained computer tasks was recorded. No effect of the training was found on cognitive functioning, QoL or self-efficacy when compared to the control condition, except for very limited effects on working memory and speed. This study found very limited effects on neuropsychological tests that were closely related to trained computer tasks, but no transfers to other tests or self-perceived cognitive failures, QoL or self-efficacy. These findings warrant the need for further research into the value of computer-based brain training to improve cognitive functioning in the chronic phase after stroke.

2015

Charvet, L., Shaw, M., Haider, L., Melville, P., & Krupp, L. (2015). Remotely-delivered cognitive remediation in multiple sclerosis (MS): protocol and results from a pilot study. Multiple Sclerosis Journal - Experimental, Translational and Clinical, 1, 205521731560962. doi:10.1177/2055217315609629

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Abstract

BACKGROUND: 

Cognitive impairment represents a critical unmet treatment need in multiple sclerosis (MS). Cognitive remediation is promising but traditionally requires multiple clinic visits to access treatment. Computer-based programs provide remote access to intensive and individually-adapted training.

OBJECTIVE: 

Our goal was to develop a protocol for remotely-supervised cognitive remediation that enables individuals with MS to participate from home while maintaining the standards for clinical study.

METHODS:

MS participants (n = 20) were randomized to either an active cognitive remediation program (n = 11) or a control condition of ordinary computer games (n = 9). Participants were provided study laptops to complete training for five days per week over 12 weeks, targeting a total of 30 hours. Treatment effects were measured with composite change via scores of a repeated neuropsychological battery.

RESULTS: 

Compliance was high with an average of 25.0 hours of program use (80% of the target) and did not differ between conditions (25.7 vs. 24.2 mean hours, p = 0.80). The active vs. control participants significantly improved in both the cognitive measures (mean composite z-score change of 0.46 ± 0.59 improvement vs. −0.14 ± 0.48 decline,p = 0.02) and motor tasks (mean composite z-score change of 0.40 ± 0.71improvement vs. −0.64 ± 0.73 decline, p = 0.005).

CONCLUSIONS: 

Remotely-supervised cognitive remediation is feasible for clinical study with potential for meaningful benefit in MS.

Donner, Y., & Hardy, J. L. (2015). Piecewise power laws in individual learning curves. Psychonomic Bulletin and Review, 22(5), 1308–1319. doi:10.3758/s13423-015-0811-x

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Abstract

The notion that human learning follows a smooth power law (PL) of diminishing gains is well-established in psychology. This characteristic is observed when multiple curves are averaged, potentially masking more complex dynamics underpinning the curves of individual learners. Here, we analyzed 25,280 individual learning curves, each comprising 500 measurements of cognitive performance taken from four cognitive tasks. A piecewise PL (PPL) model explained the individual learning curves significantly better than a single PL, controlling for model complexity. The PPL model allows for multiple PLs connected at different points in the learning process. We also explored the transition dynamics between PL curve component pieces. Performance in later pieces typically surpassed that in earlier pieces, after a brief drop in performance at the transition point. The transition rate was negatively associated with age, even after controlling for overall performance. Our results suggest at least two processes at work in individual learning curves: locally, a gradual, smooth improvement, with diminishing gains within a specific strategy, which is modeled well as a PL; and globally, a discrete sequence of strategy shifts, in which each strategy is better in the long term than the ones preceding it. The piecewise extension of the classic PL of practice has implications for both individual skill acquisition and theories of learning.

Geyer, J., Insel, P., Farzin, F., Sternberg, D., Hardy, J. L., Scanlon, M., ... Weiner, M. W. (2015). Evidence for age-associated cognitive decline from Internet game scores. Alzheimer’s and Dementia: Diagnosis, Assessment and Disease Monitoring, 1(2), 260–267. doi:10.1016/j.dadm.2015.04.002

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Abstract

INTRODUCTION:

Lumosity's Memory Match (LMM) is an online game requiring visual working memory. Change in LMM scores may be associated with individual differences in age-related changes in working memory.

METHODS:

Effects of age and time on LMM learning and forgetting rates were estimated using data from 1890 game sessions for users aged 40 to 79 years.

RESULTS:

There were significant effects of age on baseline LMM scores (β = −.31, standard error or SE = .02, P < .0001) and lower learning rates (β = −.0066, SE = .0008, P < .0001). A sample size of 202 subjects/arm was estimated for a 1-year study for subjects in the lower quartile of game performance.

DISCUSSION:

Online memory games have the potential to identify age-related decline in cognition and to identify subjects at risk for cognitive decline with smaller sample sizes and lower cost than traditional recruitment methods.

Hardy, J.L., Nelson, R.A., Thomason, M.E., Sternberg, D.A., Katovich, K., Farzin, F., & Scanlon, M. (2015). Enhancing cognitive abilities with comprehensive training: A large, online, randomized, active-controlled trial. PLoS ONE, 10(9), 1–17. doi:10.1371/journal.pone.0134467

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Abstract

BACKGROUND:

A variety of studies have demonstrated gains in cognitive ability following cognitive training interventions. However, other studies have not shown such gains, and questions remain regarding the efficacy of specific cognitive training interventions. Cognitive training research often involves programs made up of just one or a few exercises, targeting limited and specific cognitive endpoints. In addition, cognitive training studies typically involve small samples that may be insufficient for reliable measurement of change. Other studies have utilized training periods that were too short to generate reliable gains in cognitive performance.

METHODS:

The present study evaluated an online cognitive training program comprised of 49 exercises targeting a variety of cognitive capacities. The cognitive training program was compared to an active control condition in which participants completed crossword puzzles. All participants were recruited, trained, and tested online (N = 4,715 fully evaluable participants). Participants in both groups were instructed to complete one approximately 15-minute session at least 5 days per week for 10 weeks.

RESULTS:

Participants randomly assigned to the treatment group improved significantly more on the primary outcome measure, an aggregate measure of neuropsychological performance, than did the active control group (Cohen’s d effect size = 0.255; 95% confidence interval = [0.198, 0.312]). Treatment participants showed greater improvements than controls on speed of processing, short-term memory, working memory, problem solving, and fluid reasoning assessments. Participants in the treatment group also showed greater improvements on self-reported measures of cognitive functioning, particularly on those items related to concentration compared to the control group (Cohen’s d = 0.249; 95% confidence interval = [0.191, 0.306]).

CONCLUSION:

Taken together, these results indicate that a varied training program composed of a number of tasks targeted to different cognitive functions can show transfer to a wide range of untrained measures of cognitive performance.

Lim, D., Condon, P., & DeSteno, D. (2015). Mindfulness and compassion: an examination of mechanism and scalability. PloS one, 10(2), e0118221. doi:10.1371/journal.pone.0118221

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Abstract

Emerging evidence suggests that meditation engenders prosocial behaviors meant to benefit others. However, the robustness, underlying mechanisms, and potential scalability of such effects remain open to question. The current experiment employed an ecologically valid situation that exposed participants to a person in visible pain. Following three-week, mobile-app based training courses in mindfulness meditation or cognitive skills (i.e., an active control condition), participants arrived at a lab individually to complete purported measures of cognitive ability. Upon entering a public waiting area outside the lab that contained three chairs, participants seated themselves in the last remaining unoccupied chair; confederates occupied the other two. As the participant sat and waited, a third confederate using crutches and a large walking boot entered the waiting area while displaying discomfort. Compassionate responding was assessed by whether participants gave up their seat to allow the uncomfortable confederate to sit, thereby relieving her pain. Participants’ levels of empathic accuracy was also assessed. As predicted, participants assigned to the mindfulness meditation condition gave up their seats more frequently than did those assigned to the active control group. In addition, empathic accuracy was not increased by mindfulness practice, suggesting that mindfulness-enhanced compassionate behavior does not stem from associated increases in the ability to decode the emotional experiences of others.

Morrison, G.E., Simone, C.M., Ng, N.F., & Hardy, J.L. (2015). Reliability and validity of the NeuroCognitive Performance Test, A web-based neuropsychological assessment. Frontiers in Psychology, 6(NOV), 1–15. doi:10.3389/fpsyg.2015.01652

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Abstract

The NeuroCognitive Performance Test (NCPT) is a brief, repeatable, web-based cognitive assessment platform that measures performance across several cognitive domains. The NCPT platform is modular and includes 18 subtests that can be arranged into customized batteries. Here we present normative data from a sample of 130,140 healthy volunteers for an NCPT battery consisting of 8 subtests. Participants took the NCPT remotely and without supervision. Factor structure and effects of age, education, and gender were evaluated with this normative dataset. Test-retest reliability was evaluated in a subset of participants who took the battery again an average of 78.8 days later. The eight NCPT subtests group into 4 putative cognitive domains, have adequate to good test-retest reliability, and are sensitive to expected age- and education-related cognitive effects. Concurrent validity to standard neuropsychological tests was demonstrated in 73 healthy volunteers. In an exploratory analysis the NCPT battery could differentiate those who self-reported Mild Cognitive Impairment or Alzheimer's disease from matched healthy controls. Overall these results demonstrate the reliability and validity of the NCPT battery as a measure of cognitive performance and support the feasibility of web-based, unsupervised testing, with potential utility in clinical and research settings.

O’Connor, P.J., Tomporowski, P.D., & Dishman, R.K. (2015). Age Moderates the Association of Aerobic Exercise with Initial Learning of an Online Task Requiring Cognitive Control. Journal of the International Neuropsychological Society, 21(10), 802–815. doi:10.1017/S1355617715000685

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Abstract

The aim of this study was to examine whether people differed in change in performance across the first five blocks of an online flanker task and whether those trajectories of change were associated with self-reported aerobic or resistance exercise frequency according to age. A total of 8752 men and women aged 13-89 completed a lifestyle survey and five 45-s games (each game was a block of ~46 trials) of an online flanker task. Accuracy of the congruent and incongruent flanker stimuli was analyzed using latent class and growth curve modeling adjusting for time between blocks, whether the blocks occurred on the same or different days, education, smoking, sleep, caffeinated coffee and tea use, and Lumosity training status ("free play" or part of a "daily brain workout"). Aerobic and resistance exercise were unrelated to first block accuracies. For the more cognitively demanding incongruent flanker stimuli, aerobic activity was positively related to the linear increase in accuracy [B=0.577%, 95% confidence interval (CI), 0.112 to 1.25 per day above the weekly mean of 2.8 days] and inversely related to the quadratic deceleration of accuracy gains (B=-0.619% CI, -1.117 to -0.121 per day). An interaction of aerobic activity with age indicated that active participants younger than age 45 had a larger linear increase and a smaller quadratic deceleration compared to other participants. Age moderates the association between self-reported aerobic, but not self-reported resistance, exercise and changes in cognitive control that occur with practice during incongruent presentations across five blocks of a 45-s online, flanker task.

Schofield, H., Loewenstein, george, Kopsic, J., & Volpp, K.G. (2016). Comparing the effectiveness of individualistic, altruistic, and competitive incentives in motivating completion of mental exercises. Physiology & Behavior, 176(1), 139–148. doi:10.1016/j.jhealeco.2015.09.007

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Abstract

This study examines the impact of individually oriented, purely altruistic, and a hybrid of competitive and cooperative monetary reward incentives on older adults' completion of cognitive exercises and cognitive function. We find that all three incentive structures approximately double the number of exercises completed during the six-week active experimental period relative to a no incentive control condition. However, the altruistic and cooperative/competitive incentives led to different patterns of participation, with significantly higher inter-partner correlations in utilization of the software, as well as greater persistence once incentives were removed. Provision of all incentives significantly improved performance on the incentivized exercises. However, results of an independent cognitive testing battery suggest no generalizable gains in cognitive function resulted from the training.

Shute, V.J., Ventura, M., & Ke, F. (2015). The power of play: The effects of Portal 2 and Lumosity on cognitive and noncognitive skills. Computers & education, 80, 58-67. doi:10.1016/j.compedu.2014.08.013

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Abstract

In this study, we tested 77 undergraduates who were randomly assigned to play either a popular video game (Portal 2) or a popular brain training game (Lumosity) for 8 h. Before and after gameplay, participants completed a set of online tests related to problem solving, spatial skill, and persistence. Results revealed that participants who were assigned to play Portal 2 showed a statistically significant advantage over Lumosity on each of the three composite measures—problem solving, spatial skill, and persistence. Portal 2 players also showed significant increases from pretest to posttest on specific small- and large-scale spatial tests while those in the Lumosity condition did not show any pretest to posttest differences on any measure. Results are discussed in terms of the positive impact video games can have on cognitive and noncognitive skills.

2014

Ballesteros, S., Prieto, A., Mayas, J., Toril, P., Pita, C., de León, L. P., ... Waterworth, J. (2014). Brain training with non-action video games enhances aspects of cognition in older adults: A randomized controlled trial. Frontiers in Aging Neuroscience, 6(OCT), 1–14. doi:10.3389/fnagi.2014.00277

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Abstract

Age-related cognitive and brain declines can result in functional deterioration in many cognitive domains, dependency, and dementia. A major goal of aging research is to investigate methods that help to maintain brain health, cognition, independent living and wellbeing in older adults. This randomized controlled study investigated the effects of 20 1-h non-action video game training sessions with games selected from a commercially available package (Lumosity) on a series of age-declined cognitive functions and subjective wellbeing. Two groups of healthy older adults participated in the study, the experimental group who received the training and the control group who attended three meetings with the research team along the study. Groups were similar at baseline on demographics, vocabulary, global cognition, and depression status. All participants were assessed individually before and after the intervention, or a similar period of time, using neuropsychological tests and laboratory tasks to investigate possible transfer effects. The results showed significant improvements in the trained group, and no variation in the control group, in processing speed (choice reaction time), attention (reduction of distraction and increase of alertness), immediate and delayed visual recognition memory, as well as a trend to improve in Affection and Assertivity, two dimensions of the Wellbeing Scale. Visuospatial working memory (WM) and executive control (shifting strategy) did not improve. Overall, the current results support the idea that training healthy older adults with non-action video games will enhance some cognitive abilities but not others.

Dannhauser, T.M., Cleverley, M., Whitfield, T.J., Fletcher, B.C., Stevens, T., & Walker, Z. (2014). A complex multimodal activity intervention to reduce the risk of dementia in mild cognitive impairment–ThinkingFit: pilot and feasibility study for a randomized controlled trial. BMC psychiatry, 14(1), 1-9. doi:10.1186/1471-244X-14-129

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Abstract

BACKGROUND:

Dementia affects 35 million people worldwide and is currently incurable. Many cases may be preventable because regular participation in physical, mental and social leisure activities during middle age is associated with up to 47% dementia risk reduction. However, the majority of middle-aged adults are not active enough. MCI is therefore a clear target for activity interventions aimed at reducing dementia risk. An active lifestyle during middle age reduces dementia risk but it remains to be determined if increased activity reduces dementia risk when MCI is already evident. Before this can be investigated conclusively, complex multimodal activity programmes are required that (1) combine multiple health promoting activities, (2) engage people with MCI, and (3) result in sufficient adherence rates.

METHODS:

We designed the ThinkingFit programme to engage people with MCI in a complex intervention comprised of three activity components: physical activity, group-based cognitive stimulation (GCST) and individual cognitive stimulation (ICST). Engagement and adherence was promoted by applying specific psychological techniques to enhance behavioural flexibility in an early pre-phase and during the course of the intervention. To pilot the intervention, participants served as their own controls during a 6- to 12-week run-in period, which was followed by 12 weeks of activity intervention.

RESULTS:

Out of 212 MCI patients screened, 163 were eligible, 70 consented and 67 completed the intervention (mean age 74 years). Activity adherence rates were high: physical activity = 71%; GCST = 83%; ICST = 67%. Significant treatment effects (p < .05) were evident on physical health outcomes (decreased BMI and systolic blood pressure, [pre/post values of 26.3/25.9 kg/m2 and 145/136 mmHg respectively]), fitness (decreased resting and recovery heart rate [68/65 bpm and 75/69 bpm]), and cognition (improved working memory [5.3/6.3 items]).

CONCLUSIONS:

We found satisfactory recruitment, retention and engagement rates, coupled with significant treatment effects in elderly MCI patients. It appears feasible to conduct randomized controlled trials of the dementia prevention potential of complex multimodal activity programmes like ThinkingFit.

TRIAL REGISTRATION:

ClinicalTrials.gov registration nr: NCT01603862; date: 17/5/2012.

Hooker, C.I., Carol, E.E., Eisenstein, T.J., Yin, H., Lincoln, S. H., Tully, L. M., ... & Seidman, L. J. (2014). A pilot study of cognitive training in clinical high risk for psychosis: initial evidence of cognitive benefit. Schizophrenia research, 157, 314. doi:10.1016/j.schres.2014.05.034

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Abstract

This study investigated the feasibility and potential behavioral benefits of 40hours/8weeks of computer-based TCT in a single group of CHR participants. Cognitive and functional outcome were assessed with measures recommended for clinical trials, including the MATRICS Consensus Cognitive Battery (MCCB) and Global Functioning (GF): Role and Social scales(Cornblatt et al., 2007). Training performance was analyzed to: verify the relationship between training engagement and treatment outcome; identify an early predictor of treatment response; and evaluate intervention length.

Mayas, J., Parmentier, F.B., Andres, P., & Ballesteros, S. (2014). Plasticity of attentional functions in older adults after non-action video game training: a randomized controlled trial. PLoS one, 9(3), e92269. doi:10.1371/journal.pone.0092269

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Abstract

A major goal of recent research in aging has been to examine cognitive plasticity in older adults and its capacity to counteract cognitive decline. The aim of the present study was to investigate whether older adults could benefit from brain training with video games in a cross-modal oddball task designed to assess distraction and alertness. Twenty-seven healthy older adults participated in the study (15 in the experimental group, 12 in the control group. The experimental group received 20 1-hr video game training sessions using a commercially available brain-training package (Lumosity) involving problem solving, mental calculation, working memory and attention tasks. The control group did not practice this package and, instead, attended meetings with the other members of the study several times along the course of the study. Both groups were evaluated before and after the intervention using a cross-modal oddball task measuring alertness and distraction. The results showed a significant reduction of distraction and an increase of alertness in the experimental group and no variation in the control group. These results suggest neurocognitive plasticity in the old human brain as training enhanced cognitive performance on attentional functions.

Tartaglione, E.V., Derleth, M., Yu, L., & Ioannou, G.N. (2014). Can computerized brain training games be used to identify early cognitive impairment in cirrhosis?. American Journal of Gastroenterology, 109(3), 316-323. doi:10.1038/ajg.2013.306

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Abstract

OBJECTIVES:

We evaluated whether commercially available, computerized “brain-training” games can be used to identify subtle cognitive impairments in patients with cirrhosis.

METHODS:

We compared patients with cirrhosis who did not have overt encephalopathy (n=31), patients with pre-cirrhotic chronic liver disease (n=28), and normal controls without liver disease (n=16) with respect to their scores on the number connection test-A (NCT-A), the Inhibitory Control Test (ICT), and five, short (~2.5 min), brain-training games that were administered on an Apple iPad and tested different cognitive domains.

RESULTS:

Patients with cirrhosis had similar scores to patients with pre-cirrhotic liver disease and slightly worse scores than normal controls in the NCT-A and the ICT, although these differences were not statistically significant. In contrast, patients with cirrhosis had significantly worse scores than patients with pre-cirrhotic liver disease and even more so than normal controls in all five of the brain-training games. After adjustment for age and educational attainment, these differences remained significant for two of the tests, “Color Match” which is a version of the Stroop test and measures selective attention, and “Memory Matrix”, which measures visuospatial memory. The area under the receiver operating characteristic curve discriminating cirrhosis from pre-cirrhotic liver disease was 0.56 (95% confidence interval (CI) 0.41–0.72) for the ICT and 0.58 (95% CI 0.43–0.73) for the NCT-A, indicating no discrimination, while it was 0.75 (95% CI 0.63–0.87) for “Color Match” and 0.77 (95% CI 0.64–0.90) for “Memory Matrix”, indicating good discrimination.

CONCLUSIONS:

Short, brain-training games administered on an iPad can be used as psychometric tests to detect subtle cognitive impairments in patients with cirrhosis without overt encephalopathy that could not be detected by the NCT-A or the ICT.

2013

Kesler, S., Hosseini, S.H., Heckler, C., Janelsins, M., Palesh, O., Mustian, K., & Morrow, G. (2013). Cognitive training for improving executive function in chemotherapy-treated breast cancer survivors. Clinical breast cancer, 13(4), 299-306. doi:10.1016/j.clbc.2013.02.004

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Abstract

BACKGROUND:

A majority of breast cancer (BC) survivors, particularly those treated with chemotherapy, experience long-term cognitive deficits that significantly reduce quality of life. Among the cognitive domains most commonly affected include executive functions (EF), such as working memory, cognitive flexibility, multitasking, planning, and attention. Previous studies in other populations have shown that cognitive training, a behavioral method for treating cognitive deficits, can result in significant improvements in a number of cognitive skills, including EF.

MATERIALS AND METHODS:

In this study, we conducted a randomized controlled trial to investigate the feasibility and preliminary effectiveness of a novel, online EF training program in long-term BC survivors. A total of 41 BC survivors (21 active, 20 wait list) completed the 48 session training program over 12 weeks. The participants were, on average, 6 years after therapy.

RESULTS:

Cognitive training led to significant improvements in cognitive flexibility, verbal fluency and processing speed, with marginally significant downstream improvements in verbal memory as assessed via standardized measures. Self-ratings of EF skills, including planning, organizing, and task monitoring, also were improved in the active group compared with the wait list group.

CONCLUSIONS:

Our findings suggest that EF skills may be improved even in long-term survivors by using a computerized, home-based intervention program. These improvements may potentially include subjective EF skills, which suggest a transfer of the training program to real-world behaviors.

Rattray, B., & Smee, D. (2013). Exercise improves reaction time without compromising accuracy in a novel easy-to-administer tablet-based cognitive task. Journal of Science and Medicine in Sport, 16(6), 567-570. https://doi.org/10.1016/j.jsams.2012.12.007

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Abstract

OBJECTIVES:

Moderate intensity aerobic exercise is known to facilitate cognitive performance but new technologies enable increasing opportunities to investigate this phenomenon under different circumstances. This study aimed to describe the effect of exercise on executive function assessed though a novel tablet-based test.

DESIGN:

Twenty healthy, active participants volunteered to take part in the randomised fully controlled trial.

METHODS:

Participants undertook an initial test of maximal aerobic capacity as well as ventilatory threshold during an incremental cycle test. A touch screen tablet computer was placed in the middle of the handlebars at an angle of approximately 45°, and participants were asked to complete the response-inhibition cognitive task (Speed Match, Lumos Labs Inc.) at set time points. A full familiarisation trial was performed prior to subsequent visits, in which participants completed either the control (no exercise) and exercise (90% ventilatory threshold (VT)) trials in a randomised order. During the 1 h trials, the cognitive task was performed prior to, during and post the intervention. Reaction time and accuracy of participant responses were recorded.

RESULTS:

Performing the cognitive task resulted in elevated heart rates and ventilation rates during control and exercise. Exercise facilitated performance in the executive function task such that reaction time was enhanced with no change in accuracy. A range of reliability measures are also reported.

CONCLUSIONS:

This method of assessing executive function during exercise displays face validity and provides promise for further investigation of cognitive function using a simple, short duration, easily administered and widely available test.

Schneider, S., Abeln, V., Popova, J., Fomina, E., Jacubowski, A., Meeusen, R., & Strüder, H. K. (2013). The influence of exercise on prefrontal cortex activity and cognitive performance during a simulated space flight to Mars (MARS500). Behavioural brain research, 236, 1-7. doi:10.1016/j.bbr.2012.08.022

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Abstract

With respect to the plans of national and internationals space agencies to send people to Mars or Moon, long-term isolation studies are performed to learn about the psycho-physiological and psycho-social limitations of such missions. From June 3rd 2010 to November 4th 2011 six participants lived under totally isolated and confined conditions in the MARS500 habitat located in Moscow. Despite the possibility to mimic the condition of space travel, this study allowed for experimental conditions under very reliable and traceable conditions. As exercise is widely discussed to have a positive impact on neuro-cognitive performance, this study aimed to test the effect of different exercise protocol (endurance/strength orientated) on brain cortical activity and cognitive performance. Brain cortical activity was recorded using a 16 channel EEG before and after exercise across the 520 days of confinement. Cognitive performance was assessed using three commercially available brain games. Following the theory of transient hypofrontality, results show a significant decrease of frontal brain cortical activity after exercise (p<.05) which was most expressed after endurance orientated protocols. Cognitive performance was improved following running sessions on an active treadmill (p<.05). Results let us assume that not exercise per se acts as a neuro-enhancer. It is more likely that a general defocusing caused by an immersion into exercise is necessary to improve cognitive performance.

Sternberg, D.A., Ballard, K., Hardy, J.L., Katz, B., Doraiswamy, P.M., & Scanlon, M. (2013). The largest human cognitive performance dataset reveals insights into the effects of lifestyle factors and aging. Frontiers in human neuroscience, 7, 292. doi:10.3389/fnhum.2013.00292

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Abstract

Making new breakthroughs in understanding the processes underlying human cognition may depend on the availability of very large datasets that have not historically existed in psychology and neuroscience. Lumosity is a web-based cognitive training platform that has grown to include over 600 million cognitive training task results from over 35 million individuals, comprising the largest existing dataset of human cognitive performance. As part of the Human Cognition Project, Lumosity's collaborative research program to understand the human mind, Lumos Labs researchers and external research collaborators have begun to explore this dataset in order uncover novel insights about the correlates of cognitive performance. This paper presents two preliminary demonstrations of some of the kinds of questions that can be examined with the dataset. The first example focuses on replicating known findings relating lifestyle factors to baseline cognitive performance in a demographically diverse, healthy population at a much larger scale than has previously been available. The second example examines a question that would likely be very difficult to study in laboratory-based and existing online experimental research approaches at a large scale: specifically, how learning ability for different types of cognitive tasks changes with age. We hope that these examples will provoke the imagination of researchers who are interested in collaborating to answer fundamental questions about human cognitive performance.

Zickefoose, S., Hux, K., Brown, J., & Wulf, K. (2013). Let the games begin: A preliminary study using Attention Process Training-3 and Lumosity™ brain games to remediate attention deficits following traumatic brain injury. Brain injury, 27(6), 707-716. doi:10.3109/02699052.2013.775484

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Abstract

PRIMARY OBJECTIVE: Computer-based treatments for attention problems have become increasingly popular and available. The researchers sought to determine whether improved performance by survivors of severe traumatic brain injury (TBI) on two computer-based treatments generalized to improvements on comparable, untrained tasks and ecologically-plausible attention tasks comprising a standardized assessment. RESEARCH DESIGN: The researchers used an -A-B-A-C-A treatment design repeated across four adult survivors of severe TBI. METHODS AND PROCEDURES: Participants engaged in 8 weeks of intervention using both Attention Process Training-3 (APT-3) and Lumosity™ (2010) Brain Games. Two participants received APT-3 treatment first, while the other two received Lumosity™ treatment first. All participants received both treatments throughout the course of two, 1-month intervention phases. MAIN OUTCOMES AND RESULTS: Individual growth curve analyses showed participants made significant improvements in progressing through both interventions. However, limited generalization occurred: one participant demonstrated significantly improved performance on one of five probe measures and one other participant showed improved performance on some sub-tests of the Test of Everyday Attention; no other significant generalization results emerged. These findings call into question the assumption that intervention using either APT-3 or Lumosity™ will prompt generalization beyond the actual tasks performed during treatment.

2012

Koorenhof, L., Baxendale, S., Smith, N., & Thompson, P. (2012). Memory rehabilitation and brain training for surgical temporal lobe epilepsy patients: a preliminary report. Seizure, 21(3), 178-182. doi:10.1016/j.seizure.2011.12.001

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Abstract

The short term impact of a memory rehabilitation programme on verbal memory test performance and subjective ratings of memory in everyday life was assessed in healthy controls and left temporal lobe epilepsy (LTLE) surgical patients. The intervention involved training in the use of external and internal memory support strategies. Half of the sample in addition undertook computerised brain training exercises as homework. LTLE patients were seen either before surgery or 3–6 months after their operation. Improvements in verbal memory were observed in both groups. An effect of brain training was recorded but this did not occur in a consistent direction. Subjective ratings of memory indicated improvements that were significant for the LTLE group but not the controls. Positive changes in the memory outcome measures were associated with improvements in mood. Pre-operative memory rehabilitation was not associated with better outcomes than post-operative intervention. Further research is needed to explore the persistence of the changes observed and to explore if pre-operative rehabilitation offsets post-operative memory decline.

2011

Finn, M., & McDonald, S. (2011). Computerised cognitive training for older persons with mild cognitive impairment: a pilot study using a randomised controlled trial design. Brain Impairment, 12(3).

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Abstract

The results of a pilot randomised controlled trial of computerised cognitive training in older adults with mild cognitive impairment (MCI) are reported. Participants (N = 25) were randomised into either the treatment or waitlist training groups. Sixteen participants completed the 30-session computerised cognitive training program using exercises that target a range of cognitive functions including attention, processing speed, visual memory and executive functions. It was hypothesised that participants would improve with practice on the trained tasks, that the benefits of training would generalise to nontrained neuropsychological measures, and that training would result in improved perceptions of memory and memory functioning when compared with waitlist controls. Results indicated that participants were able to improve their performance across a range of tasks with training. There was some evidence of generalisation of training to a measure of visual sustained attention. There were no significant effects of training on self-reported everyday memory functioning or mood. The results are discussed along with suggestions for future research.

Hardy, J.L., Drescher, D., Sarkar, K., Kellett, G., & Scanlon, M. (2011). Enhancing visual attention and working memory with a web-based cognitive training program. Mensa Research Journal, 42(2), 13-20.

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Abstract

A variety of studies have demonstrated gains in cognitive ability following cognitive training interventions. However, other studies have not shown such gains, and questions remain regarding the efficacy of specific cognitive training interventions. Cognitive training research often involves programs made up of just one or a few exercises, targeting limited and specific cognitive endpoints. In addition, cognitive training studies typically involve small samples that may be insufficient for reliable measurement of change. Other studies have utilized training periods that were too short to generate reliable gains in cognitive performance. To address these considerations, the present study evaluated an online cognitive training program comprised of 49 distinct exercises targeting a variety of cognitive capacities. The cognitive training program was compared to an active control condition in which participants completed crossword puzzles. All participants were recruited, trained, and tested online (N=4,715 fully evaluable participants). Participants in both groups were instructed to complete one approximately 15-minute session at least 5 days per week for 10 weeks. Participants randomly assigned to the treatment group improved significantly more on the primary outcome measure, an aggregate measure of neuropsychological performance, than did the active control group. Treatment participants showed greater improvements than controls on speed of processing, short-term memory, working memory, problem solving, and fluid reasoning assessments. Participants in the treatment group also showed greater improvements

on self-reported measures of cognitive functioning, particularly on those items related to concentration. Taken together, these results indicate that a varied training program composed of a number of tasks targeted to different cognitive functions can show transfer to a wide range of untrained measures of cognitive performance.

Kesler, S.R., Lacayo, N.J., & Jo, B. (2011). A pilot study of an online cognitive rehabilitation program for executive function skills in children with cancer-related brain injury. Brain Injury, 25(1), 101-112. doi:10.3109/02699052.2010.536194

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Abstract

PRIMARY OBJECTIVES:

Children with a history of cancer are at increased risk for cognitive impairments, particularly in executive and memory domains. Traditional, in-person cognitive rehabilitation strategies may be unavailable and/or impractical for many of these children given difficulties related to resources and health status. The feasibility and efficacy of implementing a computerized, home-based cognitive rehabilitation curriculum designed to improve executive function skills was examined in these children.

METHODS:

A one-arm open trial pilot study of an original executive function cognitive rehabilitation curriculum was conducted with 23 paediatric cancer survivors aged 7-19.

RESULTS:

Compliance with the cognitive rehabilitation program was 83%, similar to that of many traditional programs. Following the cognitive intervention, participants showed significantly increased processing speed, cognitive flexibility, verbal and visual declarative memory scores as well as significantly increased pre-frontal cortex activation compared to baseline.

CONCLUSIONS:

These results suggest that a program of computerized cognitive exercises can be successfully implemented at home in young children with cancer. These exercises may be effective for improving executive and memory skills in this group, with concurrent changes in neurobiologic status.

Kesler, S.R., Sheau, K., Koovakkattu, D., & Reiss, A.L. (2011). Changes in frontal-parietal activation and math skills performance following adaptive number sense training: Preliminary results from a pilot study. Neuropsychological rehabilitation, 21(4), 433-454. doi: 10.1080/09602011.2011.578446

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Abstract

Number sense is believed to be critical for math development. It is putatively an implicitly learned skill and may therefore have limitations in terms of being explicitly trained, particularly in individuals with altered neurodevelopment. A case series study was conducted using an adaptive, computerised programme that focused on number sense and general problem-solving skills. The study was designed to investigate training effects on performance as well as brain function in a group of children with Turner syndrome who are at risk for math difficulties and altered development of math-related brain networks. Standardised measurements of math and math-related cognitive skills as well as functional magnetic resonance imaging (fMRI) were used to assess behavioural and neurobiological outcomes following training. Participants demonstrated significantly increased basic math skills, including number sense, and calculation as well as processing speed, cognitive flexibility and visual-spatial processing skills. With the exception of calculation, increased scores also were clinically significant (i.e., recovered) based on reliable change analysis. Participants additionally demonstrated significantly increased bilateral parietal lobe activation and decreased frontal-striatal and mesial temporal activation following the training programme. These findings show proof of concept for an accessible training approach that may be potentially associated with improved number sense, math and related skills, as well as functional changes in math-related neural systems, even among individuals at risk for altered brain development.