Jeannine Hirtle's List: Brain Research

"B vitamins and the aging brain examined (8/19/2010)
Tags:
vitamin b, aging

B vitamins-B-6, B-12 and folate-all nourish the brain. But much remains to be discovered about the relation between these essential nutrients and our brainpower.

U.S. Department of Agriculture (USDA) nutritionist Lindsay H. Allen has collaborated in ongoing research that has taken a closer look at the role these nutrients may play in preventing decline in brain function. The investigations, led by Mary N. Haan of the University of California-San Francisco, are part of the multiyear Sacramento (Calif.) Area Latino Study on Aging, or "SALSA." Begun in 1996, the study attracted nearly 1,800 Hispanic seniors, ages 60 to 101, as volunteers.

According to Allen, the research is needed because many studies of B vitamins and brain function have given inconsistent or conflicting results. Allen is director of the Agricultural Research Service (ARS) Western Human Nutrition Research Center in Davis, Calif. ARS is the chief intramural scientific research agency of USDA. Scientists from the University of California-Davis (UCD) and the UCD Medical Center also are collaborating in the research.

An analysis of volunteers' blood samples showed that lower levels of one B vitamin, folate, were associated with symptoms of dementia and poor brain function, also called "cognitive decline," as determined by standard tests of memory and other factors. The impairments were detectable even though less than 1 percent of the volunteers were actually deficient in folate.

In women, but not men, low levels of folate were associated with symptoms of depression. In fact, female volunteers whose plasma folate levels were in the lowest third were more than twice as likely to have symptoms of depression as volunteers in the highest third. That finding provided new evidence of an association between lower blood folate and depression. Depression is already known to affect brain function.

In research with vitamin B-12, the SALSA team determined that a protein known as holo

"Memory researchers explain latest findings on improving the mind, stopping memory loss (8/20/2010)
Tags:
memory, memory loss

The ability to remember is not just to glimpse into the past; a sharp memory can help with creativity, productivity and even the ability to imagine the future, according to several psychologists.

Sleep, aging and brain chemistry research were all discussed during several presentations on memory at the 118th Annual Convention of the American Psychological Association.

The benefits of sleep are well-documented, but researcher Sara C. Mednick, PhD, and her colleagues are finding that certain stages of sleep actually have distinct roles in people's memory capacity. The REM (rapid eye movement) sleep stage -- where people's dreams are most vivid - is also important for people's memory systems, Mednick found.

Mednick, who is a leading sleep researcher at the University of California, San Diego, presented findings from a recent study during her presentation Friday. Using a creativity task called a Remote Associates Test, study participants were shown multiple groups of three words (e.g., cookie, heart, sixteen) and asked to find another word that can be associated with all three words. In this case, the answer would have been "sweet." Participants were tested once in the morning and again in the afternoon, either after a nap with REM sleep, one without REM sleep or a quiet rest period.

Although the quiet rest and non-REM sleep groups received the same words prior to the association task, they displayed no improvement on the Remote Associates Test. However, the REM sleep group improved by almost 40 percent over their morning performances. The authors hypothesize that the formation of associative networks from previously unassociated information in the brain, leading to creative problem-solving, is facilitated by changes to neurotransmitter systems during REM sleep.

"REM sleep is important for pulling together all the information we process on a daily basis and turning it into memories we can