A recently published report funded by the National Institutes of Health (NIH) reviews the extensive literature on cognitive decline and Alzheimer’s disease in search of factors that might delay or prevent these age-related conditions. Of all the factors reviewed, including diet and dietary supplements, physical exercise, social engagement, and other leisure activities, only cognitive training was found to have a high level of evidence for being associated with a decreased risk of cognitive decline. So, if you want to engage in activities that are known to be associated with a reduced risk of cognitive decline, this report says that cognitive training is the only thing that currently fits the bill.

The nearly 800-page manuscript was prepared by the Duke Evidence-based Practice Center for the Agency of Healthcare Research and Quality (AHRQ), a part of the U.S. Department of Health and Human Services. This exhaustive report was created to support the NIH State-of-the-Science Conference “Preventing Alzheimer’s Disease and Cognitive Decline.” The conference brought together health experts with specific expertise in aging and age-related changes in cognition to discuss the current state of knowledge related to treatments for age-related cognitive decline and Alzheimer’s disease. The report takes a very conservative approach to its evaluation of risk factors and potential treatments for age-related problems of cognition. In fact, only cognitive training was found to have a high degree of evidence for reducing the risk of age-related cognitive decline. Hundreds of studies were reviewed, and while many studies offered evidence that was suggestive of reducing risks, most were correlational, rather than experimental, in nature. For instance, some studies showed a relationship between eating a “Mediterranean diet” and reduced risk of cognitive decline. But these studies typically just ask people about their diet and correlate these factors to cognitive performance. Conversely, there have been several randomized, controlled trials that have shown improved cognitive performance through cognitive training. This higher degree of rigor earned cognitive training the “high degree of evidence” designation in this report.

Of course, that’s not to say you shouldn’t take care of yourself in other ways. Other factors such as a diet high in vegetables and omega-3 fatty acids, physical activity, and some leisure activities were found to be associated with a decreased risk of cognitive decline, albeit with a low level of evidence. In other words, these things are likely good for your brain, but the authors did not feel there was enough evidence to say so definitively. Given that most of these lifestyle factors are good for you in other ways, there’s certainly no harm in eating better, getting more exercise, or spending more time with friends and family. If you want to see how your lifestyle may be affecting your brain health, take our Brain Grade test.

This report is just another reason to make cognitive training — like Lumosity.com — a regular part of your brain health routine.

Working memory training has been shown to be effective in improving fluid intelligence in humans. Now, research out of Rutgers has shown a similar effect in mice. This finding in mice reinforces the idea that brain enhancement through neuroplasticity is generally possible among mammals, and it opens up exciting possibilities for future research.

Researchers trained mice on a task that exercised working memory and attention, and measured their ability to perform a range of mentally challenging tasks before and after training. The mice that received focused brain training improved on measures of generalized cognitive function compared to control mice with no training. The researchers, who recently published this work in the prestigious journal Current Biology, imply that you can think of these tests as IQ tests for mice. In other words, working memory training seems to have actually made these mice smarter!

For training, the mice needed to simultaneously remember two maze configurations, and be able to make their way through either one. The mice then completed several tests to measure the effect of the training on their intelligence and ability to learn. The training made the mice better at tests that didn’t involve mazes at all, like learning how to avoid an unpleasant stimulus.

So, as in brain training studies in humans, the mice didn’t just get better at what they were practicing – they also became generally more intelligent. This transfer of training is the gold standard in assessing the effectiveness of brain training. Transfer implies that underlying brain systems are fundamentally changed by the learning, and it’s not just that the subject learned how to take the test.

This kind of transfer has been shown many times in human studies — including transfer from speed of processing training to driving ability, auditory processing training to memory performance, and working memory training to fluid intelligence — but, this is the first such result demonstrated in a non-human animal. This is significant for a few reasons. First of all, it implies that improvement in general cognitive function with brain training is a fundamental capacity of the mammalian brain, not just a human trait. Also, this paradigm allows for research that is difficult to perform on humans. The environment of mice can be very carefully controlled, eliminating many of the confounding variables inherent in research on humans. Researchers can breed mice to have certain characteristics and even knock out certain genes and replace them with others. This opens up the possibility of testing the effects of brain training on conditions like Alzheimer’s Disease, for which there are mouse models. Many new avenues of research are opened by the demonstration of this effect in mice.

This result represents an important milestone in study of brain training! It reinforces what we already know — the brain is highly adaptable and can be improved with training, and it gives us new avenues to explore. We’re looking forward to seeing what this team comes up with next.

Joe Hardy, PhD

This document describes the background brain science, the principles upon which the brain games and courses were designed, and some of the research done using Lumosity. The goal was to break down the science of Lumosity into terms that anyone can understand while creating a comprehensive and precise presentation of the research.

Check it out, and let us know what you think.

Joe Hardy, PhD

Training with cognitive exercises can improve targeted mental functions, conclude the authors of a review article published recently in the journal Alzheimer’s and Dementia.  The authors (Kathryn Papp and Stephen Walsh from the University of Connecticut and Peter Snyder from Brown University) reviewed ten randomized controlled trials involving cognitive training interventions in healthy adults published since 1992.  They find that specific abilities such as memory, reasoning, and speed of processing can be improved through targeted training programs.  This is an important conclusion, and it is consistent with the growing evidence in support of the effectiveness of cognitive training.

The authors point out that the benefits of cognitive training tend to be specific to the trained domain.  So, if you want improved memory — train on games designed to improve memory.  If you want improved attention — train with attention games, and so on.  The relationship to physical exercise is apparent.  If you want big biceps — do curls.  If you want ripped abs — do sit ups.  Lumosity was designed with these principles in mind.  This is why the site contains over 30 games targeting cognitive functions spanning speed of processing, memory, attention, flexibility, and problem solving — a complete gym for the brain.

It is also clear from this review that there is still much to learn.  Few of the studies have follow-up testing longer than a few months, and many of them lack measures of real-world benefits such as activities of daily living.  However, where longer follow-ups and real-world benefits are measured, benefits are seen to be long lasting and quite general.  For example, in the ACTIVE study of cognitive training in normal healthy older adults, benefits to activities of daily living are seen 5 years after the training intervention ended.

While there is still much to learn, the weight of the evidence is showing that cognitive training can be highly effective when properly designed and executed.

Can you actually become more intelligent?  For years, neuroscientists thought that this basically didn’t happen.  According to this view, you can take in more information and learn new things, but you can’t really become “more intelligent.”  Recent research conducted by scientists at the University of Michigan shows that this old view is probably dead wrong.

Susanne Jaeggi, Martin Buschkuehl, and their colleagues at Michigan did a study looking at what happens when people play a challenging working memory task called Dual N-Back.  They found that after training on this task for 25 minutes a day for a few weeks, the young adults in their study actually scored much better on tests of fluid intelligence – the ability to creatively solve new problems.  Fluid intelligence is part of standard IQ tests, so we can say that these subjects actually increased their intelligence following this training.

The Dual N-Back training is now available (free for a limited time) on Lumosity!  We have worked closely with Dr. Jaeggi and Dr. Buschkuehl to create a version of the Dual N-Back training that replicates what was used in their earlier study.  And, we’re going to support their ongoing research by hosting the program which will be used in their studies of intelligence training going forward.

Try it for yourself, but be warned: this training is not for the faint of heart. It’s hard! But the effort is worth it. After you’ve started, why not share your experiences with other users in our dual n-back forum?

Eating lots of fish, the ultimate brain food, was recently associated with reduced risk of stroke.

A study conducted by Jyrki Virtanen and his crew at the University of Kuopio in Finland found that people who ate more fish tended to have fewer strokes. Virtanen looked at a population of 2,313 participants over the age of 65 who had their brains scanned (via MRI) twice, with a 5-year lapse between scans. After analyzing answers the participants gave to diet-related questionnaires the researchers found that:

• Those eating fish 3 or more times a week had fewer sub-clinical infarcts or “mini-strokes” than those eating fish less than once a month.
• Consuming more fish was associated with more intact brain white matter.
• Fried fish is not so healthy, and seemed to negate the above benefits.

As seen in other research studying healthy brain food, omega-3 fatty acids, which are present in most fish oils, seem to be a key contributor to lowering the risk of stroke.

Reference: Virtanen, J. K., Siscovick, D. S., Longstreth, W. T., Kuller, L. H., & Mozaffarian, D. (2008). Fish consumption and risk of subclinical brain abnormalities on MRI in older adults. Neurology, 71(6), 439-446.

It seems that working memory training may work by physically altering the brain. Stockholm Brain Institute researchers put healthy people through working memory exercises for 35 minutes per day over a period of 5 weeks. Changes in dopamine receptor density were measured with positron emission tomography (PET) before and after the training.

Following working memory training, they found:

• An increase in the density of dopamine receptors.
• An improvement in working memory performance.

The neurotransmitter dopamine plays a central role in working memory. This research implies that improving working memory performance through several weeks of training might work by increasing the quantity of dopamine receptors in the brain.

References:
Buschkuehl, M., Jaeggi, S. M., Hutchison, S., Perrig-Chiello, P., Däpp, C., Müller, M., et al. (2008). Impact of working memory training on memory performance in old-old adults. Psychology and Aging, 23(4), 743-53.

Dahlin, E., Neely, A. S., Larsson, A., Bäckman, L., & Nyberg, L. (2008). Transfer of learning after updating training mediated by the striatum. Science (New York, N.Y.), 320(5882), 1510-2.

McNab, F., Varrone, A., Farde, L., Jucaite, A., Bystritsky, P., Forssberg, H., et al. (2009). Changes in cortical dopamine D1 receptor binding associated with cognitive training. Science (New York, N.Y.), 323(5915), 800-2.

A new study indicates that focusing too much might actually diminish your ability to pay attention. The researchers, based out of Carnegie Mellon University, used a phenomenon called the attentional blink as the center of their investigation.

An attentional blink is a deficit in visual attention which often occurs 200-500 milliseconds after the first of two visual items are presented during an experiment. The study looked at the ability of participants to detect that second visual item in the presence of visual distractions (moving grey dots).

Surprisingly, the distractors enhanced the ability of people to detect items often obscured by attentional blinks.

The authors hypothesize that the attentional blink phenomenon is due to an overexertion of control happening when target detection and memory consolidation overlap.

They surmise that the adding of distractors dissipates this overexertion of control, thereby enhancing performance.

So the next time you’re playing Speed Match you may want to try day dreaming a bit…it just might improve your score.

References:
Taatgen, N. A., Juvina, I., Schipper, M., Borst, J. P., & Martens, S. (n.d.). Too much control can hurt: A threaded cognition model of the attentional blink. Cognitive Psychology, In Press, Corrected Proof.

Salvucci, D. D., & Taatgen, N. A. (2008). Threaded cognition: An integrated theory of concurrent multitasking. Psychological
Review, 115(1), 101–130.

Newswise— Individuals with higher education levels appear to score higher on cognitive tests despite having evidence of brain plaques associated with Alzheimer’s disease, according to a report in the November issue of Archives of Neurology, one of the JAMA/Archives journals.

The cognitive reserve hypothesis holds that individuals with greater cognitive (thinking, learning and memory) abilities are able to delay symptoms of Alzheimer’s disease despite underlying changes in the brain, according to background information in the article. Education is commonly used as a substitute measure of cognitive reserve. “Adjusting for level of Alzheimer disease pathological burden determined at autopsy, greater education has been associated with better cognitive function during life,” the authors write. “Education interacts with Alzheimer disease pathological burden such that a greater pathological burden is required to show an effect on cognition among persons with more education.”

Catherine M. Roe, Ph.D., and colleagues at the Washington University School of Medicine, St. Louis, studied 37 individuals with dementia of the Alzheimer type and 161 individuals without dementia between 2003 and 2008. Participants reported their education history and took cognitive tests. They were injected with a marker known as carbon 11–labeled Pittsburgh Compound B ([11C]PiB) and then underwent a 60-minute positron emission tomography (PET) scan of the brain. Recent studies have shown that [11C]PiB adheres to beta-amyloid brain plaques associated with Alzheimer’s disease, allowing researchers to identify these characteristics of the disease in living patients.

The level of [11C]PiB uptake interacted significantly with years of education in predicting cognitive test scores. Among individuals whose brains took up higher levels of [11C]PiB, indicating the presence of beta-amyloid plaques, performance on the test increased with increasing education levels. Education was not associated with cognitive scores among those with low [11C]PiB uptake, indicating no plaques.

“The results support the hypothesis that cognitive reserve influences the association between Alzheimer disease pathological burden and cognition,” the authors write. “Based on autopsy data, there may be a ceiling effect when extensive beta-amyloid pathological burden is present as in late-stage dementia of the Alzheimer type. Presumably, as the Alzheimer disease pathological burden increases, a greater proportion of highly educated participants reaches the threshold for dementia and the initial advantage provided by cognitive reserve decreases. Longitudinal imaging of beta-amyloid pathology in vivo will soon allow us to determine whether these inferences from cross-sectional studies are accurate.”

Reference: Arch Neurol. 2008;65[11]:1467-1471

A recent research review to be published in the journal Progress in Neuropsychopharmacology & Biological Psychiatry shows a link between cigarette smoking and adverse changes in the function and physiology of the brain. Summarizing the findings of dozens of experiments, the review indicates that:

• Strokes are more prevalent in smokers than non-smokers.
• Gray matter (made up of brain cells) shrinks in long-term smokers.
• Smoking is associated with less integrity in the white matter connecting brain hemispheres.
• Puffing tobacco can be bad for neurotransmitters.

There are a few factors clouding the picture however. These include the fact that alcohol consumption often accompanies cigarette smoking and has also been shown to have detrimental effects on the brain.

In addition there is the question of which comes first: brain abnormalities or smoking habits. It is possible that preexisting brain abnormalities increase the likelihood of smoking and addiction.  The author suggested more research in order to answer these questions, as well as to determine if these symptoms are reversible after quitting.

References:

Domino, E. (2008). Tobacco Smoking and MRI/MRS Brain Abnormalities Compared to Nonsmokers. Progress in Neuro-Psychopharmacology and Biological Psychiatry, In press.