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.

Your brain is made up of 60% water and many of us may not be drinking enough of the clear wet stuff to keep our thinking “juicy.”

Not drinking enough water has detrimental effects on our brains. When your body lacks water, brain cells and other neurons shrink and biochemical processes involved in cellular communication slow. A drop of as little as 1 to 2% of fluid levels can result in slower processing speeds, impaired short-term memory, tweaked visual tracking and deficits in attention.

With proper hydration however, neurons work best and are capable of reacting faster.

What constitutes proper hydration is controversial. Some say that it is important to imbibe 8 tall glasses of water daily, while others claim that one should only drink when thirsty.

In fact, there is no one golden rule to staying well hydrated. The amount of water each of us needs varies from person to person as it depends on each individual’s physiology and lifestyle activities like diet and exercise.

Experiment and see what feels good. In today’s world of infinite distractions however, it is best not to leave hydration to your sense of thirst alone. It is also important to note that your ability to notice thirst typically diminishes with age.

Also of note:

• Sweating from exercise or high temperatures can result in more than 3 liters an hour of fluid loss.
• The maximum amount of water the body is capable of absorbing is 1 liter an hour or 330 milliliters every 20 min (the ideal amount to drink under high sweat conditions).
• Although good for energy, foods high in protein and sugar increase the body’s need for water.

Warning!

Drinking too much water is very dangerous! Over-hydration causes a sodium imbalance that can be fatal. It is common for marathon runners to be hospitalized because of overzealous hydration during the race.

Approach fluid consumption with moderation.

References:

Armstrong, L. E., & Epstein, Y. (1999). Fluid-electrolyte balance during labor and exercise: concepts and misconceptions. International Journal of Sport Nutrition, 9(1), 1-12.

Kleiner, S. M. (1999). Water: an essential but overlooked nutrient. Journal of the American Dietetic Association, 99(2), 200-6.

Lang, F., Busch, G. L., Ritter, M., Völkl, H., Waldegger, S., Gulbins, E., et al. (1998). Functional significance of cell volume regulatory mechanisms. Physiological Reviews, 78(1), 247-306.

Lieberman, H. R. (2007). Hydration and cognition: a critical review and recommendations for future research. Journal of the American College of Nutrition, 26(5 Suppl), 555S-561S.

Maughan, R. J., Shirreffs, S. M., & Watson, P. (2007). Exercise, heat, hydration and the brain. Journal of the American College of Nutrition, 26(5 Suppl), 604S-612S.

Murray, R. (1998). Rehydration strategies–balancing substrate, fluid, and electrolyte provision. International Journal of Sports Medicine, 19 Suppl 2, S133-5.

Suhr, J. A., Hall, J., Patterson, S. M., & Niinistö, R. T. (2004). The relation of hydration status to cognitive performance in healthy older adults. International Journal of Psychophysiology: Official Journal of the International Organization of Psychophysiology, 53(2), 121-5.

It turns out there may be a link between cardiovascular fitness and the size of one’s hippocampus, a portion of the brain important for the formation of new memories.

Researchers from the University of Illinois and the University of Pittsburgh, looked at the cardiovascular fitness of 165 adults between the ages of 59 and 81. They also measured (via MRI) the size of each participant’s hippocampus and tested for spatial reasoning abilities.

What they found:

• Elderly adults who are physically fit tend to have larger hippocampi than those who are less fit.
• Having a larger hippocampus is correlated with better performance on spatial memory tasks.

Exercise has been linked to hippocampus size and spatial memory in rodents, but this is the first study to demonstrate a similar relationship in humans.

This is good news because although variable between individuals, it is well established that the hippocampus typically shrinks with age and that this shrinkage is associated with subtle but definite declines in memory and spatial orientation.

References:

Erickson, K. I., Prakash, R. S., Voss, M. W., Chaddock, L., Hu, L., Morris, K. S., et al. (2009). Aerobic fitness is associated with hippocampal volume in elderly humans. Hippocampus.

Kitabatake, Y., Sailor, K. A., Ming, G., & Song, H. (2007). Adult neurogenesis and hippocampal memory function: new cells, more plasticity, new memories? Neurosurgery Clinics of North America, 18(1), 105-13, x.

A study of brain function in mice reveals that a stimulating environment improves the memory of their offspring. If this improvement also occurs in humans, a mother’s youthful experiences may help shape her childrens’ ability to learn. Here’s the press release, with the paper reference below the fold:

Newswise — A study reveals that the severity of learning disorders may
depend not only on the child’s environment but also – remarkably – on
the mother’s environment when she was young. The study in
memory-deficient mice, published in the February 4 issue of The
Journal of Neuroscience, was led by Larry Feig, PhD, professor of
biochemistry at Tufts University School of Medicine and member of the
biochemistry and neuroscience programs at the Sackler School of
Graduate Biomedical Sciences at Tufts University.

The researchers studied the brain function of pre-adolescent mice with
a genetically-created defect in memory. When these young mice were
enriched by exposure to a stimulating environment – including novel
objects, opportunities for social interaction and voluntary exercise –
for two weeks, the memory defect was reversed. The work showed that
this enhancement was remarkably long-lasting because it was passed on
to the offspring even though the offspring had the same genetic
mutation and were never exposed to an enriched environment.

Previous research has shown that environmental exposures during
pregnancy can affect offspring. “A striking feature of this study is
that enrichment took place during pre-adolescence, months before the
mice were even fertile, yet the effect reached into the next
generation,” said Feig.

“The offsprings’ improved memory was not the result of better
nurturing by mothers who were enriched when they were young. When the
offspring were raised by non-enriched foster mothers, the offspring
maintained the beneficial effect,” said co-author Junko Arai, PhD,
postdoctoral associate in Feig’s laboratory.

“The effect lasted until adolescence, when it waned, suggesting that
this process is designed specifically to aid the young brain,”
continued Shaomin Li, PhD, MD, co-author, former postdoctoral
associate in Feig’s laboratory, now at Brigham and Women’s Hospital.

“This example of ‘inheritance of acquired characters,’ was first
proposed by Lamarck in the early 1800s. However, it is incompatible
with classical Mendelian genetics, which states that we inherit
qualities from our parents through specific DNA sequences they
inherited from their parents. We now refer to this type of inheritance
as epigenetics, which involves environmentally-induced changes in the
structure of DNA and the chromosomes in which DNA resides that are
passed on to offspring,” said Feig.

Previous research by Feig and his team showed that a relatively brief
exposure to an enriched environment in both normal and
memory-deficient mice unlocks an otherwise latent biochemical control
mechanism that enhances a cellular process in nerve cells called
long-term potentiation (LTP), which is known to be involved in
learning and memory. This enhancement was detected in pre-adolescent
mice but not in adult mice, reflecting the brain’s higher plasticity
in the young.

Feig concluded that the transgenerational inheritance of the effect of
an enriched environment may be a mechanism that has evolved to protect
one’s offspring from deleterious effects of sensory deprivation, which
may be particularly potent in the young and exacerbated in the
learning disabled.

Junko Arai and Shaomin Li, first authors, contributed equally to the
paper. Dean M. Hartley, PhD, of Rush University Medical Center is also
an author.

The work was supported by the National Cancer Institute of the
National Institutes of Health because these findings were derived as
an offshoot of the Feig lab’s long-term experience working on Ras
proteins that are involved in cancer. Fundamental principles of how
Ras proteins function gained by studying its role in cancer expedited
subsequent studies on Ras function in the brain. This work highlights
how major breakthroughs can arise by allowing researches to follow new
leads that cross disciplines. The work was also supported by the Tufts
Center for Neuroscience Research.

Arai J, Li S, Hartley DM, and Feig LA. The Journal of Neuroscience.
2009. (February 4); 29(5): 1496-1502. “Transgenerational Rescue of a
Genetic Defect in Long-Term Potentiation and Memory Formation by
Juvenile Enrichment.” Published online February 3, 2009, doi:
10.1523/JNEUROSCI.5057-08.2009

About Tufts University School of Medicine
Tufts University School of Medicine and the Sackler School of Graduate
Biomedical Sciences at Tufts University are international leaders in
innovative medical education and advanced research. The School of
Medicine and the Sackler School are renowned for excellence in
education in general medicine, special combined degree programs in
business, health management, public health, bioengineering, and
international relations, as well as basic and clinical research at the
cellular and molecular level. Ranked among the top in the nation, the
School of Medicine is affiliated with six major teaching hospitals and
more than 30 health care facilities. The Sackler School undertakes
research that is consistently rated among the highest in the nation
for its impact on the advancement of medical science.

Data collected by Agnes Flöel and her crew at the University of Munster in Germany seems to give yet another reason to resist that second helping of chocolate cake.

The research compared short-term memory performance of overweight individuals who reduced their caloric intake by 30% over 3 months with individuals who maintained their regular diet over the same 3 months.

Results:

• After 3 months, those on the decreased calorie diet improved by 20% on short-term memory tests of word recall.
• Participants who did not change their caloric intake showed no improvements.

The study coincides with multiple other studies demonstrating improved brain plasticity in animals fed calorie restricted diets. Some possible mechanisms at work include:

• The modified action of neurotransmitters
• The stimulation of neurogenesis (production of neurons)
• Increases in cell metabolism

However, in the above study, there may be other factors at work. As all the participants were overweight to begin with, the improvements could simply be due to an increase in overall health (IE blood flow, increased oxygen etc). Studies “starving” healthy individuals seem to be called for in order to eliminate this possibility.

References:
Caloric restriction improves memory in elderly humans. (2009, January 26). . Retrieved January 27, 2009, from http://www.pnas.org/content/early/2009/01/26/0808587106.

Fontán-Lozano, A., Sáez-Cassanelli, J. L., Inda, M. C., de los Santos-Arteaga, M., Sierra-Domínguez, S. A., López-Lluch, G., et al. (2007). Caloric restriction increases learning consolidation and facilitates synaptic plasticity through mechanisms dependent on NR2B subunits of the NMDA receptor. The Journal of Neuroscience: The Official Journal of the Society for Neuroscience, 27(38), 10185-95. doi: 10.1523/JNEUROSCI.2757-07.2007.

Stranahan, A., & Mattson, M. (2008). Impact of Energy Intake and Expenditure on Neuronal Plasticity. Neuromolecular Medicine.

Recent findings have linked exercising regularly with increased cerebral blood flow and a greater number of blood vessels in the brain.

While it has been shown in the past that aerobic exercise might reduce cognitive decline, this study demonstrated a possible explanation: changes in the brain’s blood vessels and blood flow.

The researchers recruited 12 healthy adults, age 60 to 76. Six of the adults participated in aerobic exercise for three or more hours per week over 10 years, and six exercised less than one hour per week. All of the volunteers underwent MRI to determine cerebral blood flow and MR angiography to depict blood vessels in the brain.

Compared to the inactive group, the people who exercised regularly had more small blood vessels carrying blood through the brain, and the blood flowed in a more normal pattern.

Think you’re good at multitasking? Many people believe they get more done by doing several things at once, but usually they’re wrong. Every time you switch to a different activity, you must give up a moment to shift your attention to the new task at hand. Overall, doing more than one thing slows you down.

While it’s a good idea to avoid multitasking in your day-to-day activities, some multitasking is simply unavoidable. So, we’ve designed Brain Shift to help you become better at efficiently switching between different activities. You should still avoid multitasking when possible, but we hope this exercise will make you better at it for those times when you must.

You can find Brain Shift here: http://games.lumosity.com/brain_shift.html

Let us know what you think!

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.

This new exercise will work your mental flexibility, logical problem solving, and working memory abilities. We’re still putting the final touches on it, so send us your feedback so we can keep making it better.

You can find By the Rules here: http://games.lumosity.com/by_the_rules.html

The field of neuroscience is just beginning to understand some of the physiological foundations of how we learn. The following is a basic breakdown of what we think we might know.

Learning is the process by which new knowledge or skills sticks to our brains.  Its functional “sticky” unit is the neuron. Neurons are cells specially adapted to communicate with each other. Everything we experience is reflected in the brain by neurons which communicate to form what are called neural networks.  These networks can be pictured as overlapping 3-D road maps which span brain regions responsible for processing everything from the bitter-sweet taste of dark chocolate to why your neighbor is such a grump. As we learn, these neural “road maps” interact and shift while also fading or strengthening in relation to our experiences.

Whether it be recognizing a co-worker or changing a flat tire, learning entails the formation and strengthening of connections or synapses between neurons. Brief experiences typically leave connections tracing an ephemeral neural network. This might be envisioned as crisscrossing deer paths. Which, if left unused, fade quickly.

After repeated exposure to a learning experience, like the second time we change that flat tire, the associated neuronal connections are reinforced, resembling more a network of single lane country roads than deer paths.  And when it comes to daily practice and expertise in a skill, one can imagine that the guy at the local tire shop would have the neuronal equivalent of intersecting super-highways.

This strengthening of neural network connections is thought to be the physiological basis of learning.

Changing, strengthening and creating new neural networks tends to get more difficult with age. There is some research, however, indicating that it is possible to maintain our ability to learn, and possibly even ward off or lessen the impact of certain types of dementia. It appears that a significant amount of age related cognitive decline can be attributed to a tendency to stay within pre-established comfort zones; shying away from new and challenging experiences, which typically push the brain to grow (or at least not shrink as fast).

Here are some simple tips that could help maintain our brain’s ability to adapt.

• Stay Social- Reaching out and staying connected with friends and family engages the mind.

• Break a Sweat- It’s not only good for your body but your head as well.  Regular aerobic exercise is even capable of stimulating the formation of new neurons.

• Relax- Certain stress hormones are damaging to the brain in excess.

• Seek Challenges- Take that swing dance class, it’ll keep you on your toes in more ways than one. Do a variety of the Lumosity brain games – don’t just focus on your favorites.

• Eat Fruits and Veggies- You’ve heard it a million times before; this time it’s because they contain anti-oxidants and other substances protective of your head’s contents.

• Review Your Day- Take some evening time to review what you did, who you met, and what you read about. Start with the present and work your way back to breakfast or vice a versa.