Older news items (pre-2010) brought over from the old website
Exercise can aid recovery after brain radiation
A mouse study has found that exercise can prevent a decline in memory after whole-brain radiation treatment. Mice that had radiation plus access to a running wheel did as well at remembering where an escape hole in maze was as normal mice that didn't exercise. Irradiated mice that had no access to an exercise wheel eventually showed no particular preference for the section of the maze with the escape hole. The irradiated mice who didn’t exercise also showed depressive-like behavior, while those who exercised did not.
Wong-Goodrich, S.J. et al. 2009. Exercise promotes recovery from cognitive dysfunction, depressive-like behavior, and loss of hippocampal neurogenesis following whole-brain irradiation in adult mice. Presented October 20 at the annual Society for Neuroscience meeting in Chicago.
http://www.eurekalert.org/pub_releases/2009-10/dumc-eca101309.php
Older adults
Maintaining or Increasing Activity Levels May Slow Cognitive Decline in Elderly
A 7-year study of over 3000 seniors (70-79) using self-report physical activity (walking) found that 21% were consistently sedentary, 12% maintained their activity levels, 26% had declining levels, and 41% had increasing or fluctuating levels. After adjustment for age, sex, race, education, study site, diabetes, hypertension, smoking, alcohol consumption and baseline cognitive score, they found that those who were sedentary throughout the study had the lowest levels of cognitive function at the beginning and experienced the fastest rate of cognitive decline; cognitive decline also was faster in those whose physical activity levels consistently declined during the study period. However, sedentary elders who increased their physical activity improved their cognitive function, especially the ability to process complex information quickly.
Barnes, D.E. et al. 2009. The impact of changes in physical activity levels on rate of cognitive decline in a biracial cohort of non-demented elders. Presented at the Alzheimer's Association International Conference on Alzheimer's Disease July 11-16 in Vienna.
http://www.eurekalert.org/pub_releases/2009-07/aa-ah070209.php
Whether lifelong physical activity helps or hurts the aging brain depends on extent
A study of 90 post-menopausal women found that long-term strenuous activity was consistently associated with poorer performance on all eight cognitive tests, in particular tests of semantic memory, working memory, delayed verbal recall, and sustained attention. However, moderate physical activity was consistently associated with better performance on all eight of the tests, especially cognitive flexibility, working memory, and sustained attention.
Tierney, M.C. et al. 2009. Intensity of long-term physical activity and later life cognition in postmenopausal women. Presented at the Alzheimer's Association International Conference on Alzheimer's Disease July 11-16 in Vienna.
http://www.eurekalert.org/pub_releases/2009-07/aa-ah070209.php
Alzheimer's Gene May Reduce Benefits of Physical Activity for Cognitive Ability
A study of some 1800 seniors (60+) found that the association of physical activity with better cognitive function was significant only for those who didn’t carry any copies of the “Alzheimer’s gene” APOE-e4 (which is the majority of people), and was greater with age.
Obisesan, T.O., Hamilton, J. & Gillum, R.F. 2009. Aerobic-related physical activity interacting with apolipoprotein E genotypes, is associated with better cognitive function in a nationally representative sample: The Third National Health and Nutrition Examination Survey (NHANES III). Presented at the Alzheimer's Association International Conference on Alzheimer's Disease July 11-16 in Vienna.
http://www.eurekalert.org/pub_releases/2009-07/aa-ah070209.php
Physical fitness improves memory in seniors
A study of 165 older adults (59-81) has found a significant association between physical fitness and performance on certain spatial memory tests. Fitness was also strongly correlated with hippocampus size. Although rodent studies have shown that exercise increases hippocampus size and spatial memory, this is the first study to show that in humans. The findings provide more evidence for the benefits of physical exercise in preventing memory loss in older adults.
[404] Kramer, A. F., Erickson K. I., Prakash R. S., Voss M. W., Chaddock L., Hu L., et al.
(2009). Aerobic fitness is associated with hippocampal volume in elderly humans.
Hippocampus. 19(10), 1030 - 1039.
http://www.eurekalert.org/pub_releases/2009-02/uoia-pfi022409.php
Exercise prevents stem cell drop in middle age
Following mouse research showing that the creation of new brain cells (neurogenesis) in the dentate gyrus drops off dramatically by the time mice are middle aged and that exercise can significantly slow that trend, a new mouse study has confirmed these findings and found evidence that exercise has this effect by increasing the production of BDNF.
[990] Wu, C-W., Chang Y-T., Yu L., Chen H-ing., Jen C. J., Wu S-Y., et al.
(2008). Exercise enhances the proliferation of neural stem cells and neurite growth and survival of neuronal progenitor cells in dentate gyrus of middle-aged mice.
J Appl Physiol. 105(5), 1585 - 1594.
http://www.eurekalert.org/pub_releases/2008-11/aps-eib111708.php
Age differences in cognitive benefits of exercise and mental stimulation
A mouse study has found that while physical exercise (a running wheel) and mental stimulation (toys), singly and together, improved memory in old mice, exercise alone or exercise and stimulation improved memory in middle-aged mice but not stimulation alone, and only exercise alone benefited young mice. The results suggest that as we get old and maybe less able to exercise, cognitive stimulation can help to compensate, but exercise is central to memory reinforcement at all ages.
[751] Harburger, L. L., Nzerem C. K., & Frick K. M.
(2007). Single enrichment variables differentially reduce age-related memory decline in female mice.
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Behavioral Neuroscience. 121(4), 679 - 688.
Full text available at http://www.apa.org/journals/releases/bne1214679.pdf
http://www.eurekalert.org/pub_releases/2007-08/apa-eam080107.php
Fitness and childhood IQ indicators of cognitive ability in old age
Data from the Scottish Mental Survey of 1932 has revealed that physical fitness contributed more than 3% of the differences in cognitive ability in old age. The study involved 460 men and women, who were tested using the same cognitive test at age 79 that they had undergone at age 11. Physical fitness was defined by time to walk six meters, grip strength and lung function. Childhood IQ was also significantly related to lung function at age 79, perhaps because people with higher intelligence might respond more favorably to health messages about staying fit. But physical fitness was more important for cognitive ability in old age than childhood IQ. People in more professional occupations and with more education also had better fitness and higher cognitive test scores at 79.
[770] Deary, I. J., Whalley L. J., Batty D. G., & Starr J. M.
(2006). Physical fitness and lifetime cognitive change.
Neurology. 67(7), 1195 - 1200.
http://www.eurekalert.org/pub_releases/2006-10/aaon-fac100306.php
Exercise helps sustain mental activity as we age
A review of the research on the effects of exercise on brain functioning supports the view that physical exercise helps people maintain cognitive abilities well into older age. There’s also evidence that fitness training may improve some mental processes even more than moderate activity. The review examined three types of study: epidemiological studies, human intervention studies, and animal studies. All provide support for the benefits of physical activity for the aging brain.
Kramer, A.F., Colcombe, S.J., Erickson, K. & Scalf, P. 2006. Fitness Training and the Brain: From Molecules to Minds. Presented August 11 at the 114th Annual Convention of the American Psychological Association (APA).
http://www.eurekalert.org/pub_releases/2006-08/apa-ehs080106.php
Simple Lifestyle Changes May Improve Cognitive Function
A study involving 17 people (35–69 years) with mild self-reported memory complaints but normal baseline memory performance scores, has found that 2 weeks on a program combining a brain healthy diet plan (5 small meals a day; diet rich in omega-3 fats, antioxidants and low-glycemic carbohydrates like whole grains), relaxation exercises, cardiovascular conditioning (daily walks), and mental exercise (such as crosswords and brain teasers) resulted in participants' brain metabolism decreasing 5% in working memory regions (left dorsolateral prefrontal cortex), suggesting an increased efficiency. Compared to the control group, participants also performed better in verbal fluency.
Small, G.W. et al. 2006. Effects of a 14-Day Healthy Longevity Lifestyle Program on Cognition and Brain Function. American Journal of Geriatric Psychiatry, 14, 538-545.
http://www.newsroom.ucla.edu/page.asp?RelNum=7062
Review supports link between lifestyle factors and cognitive function in older adults
A review of 96 papers involving 36 very large, ongoing epidemiological studies in North America and Europe looking at factors involved in maintaining cognitive and emotional health in adults as they age has concluded that controlling cardiovascular risk factors, such as reducing blood pressure, reducing weight, reducing cholesterol, treating (or preferably avoiding) diabetes, and not smoking, is important for maintaining brain health as we age. The link between hypertension and cognitive decline was the most robust across studies. They also found a consistent close correlation between physical activity and brain health. However, they caution that more research is needed before specific recommendations can be made about which types of exercise and how much exercise are beneficial. They also found protective factors most consistently reported for cognitive health included higher education level, higher socio-economic status, emotional support, better initial performance on cognitive tests, better lung capacity, more physical exercise, moderate alcohol use, and use of vitamin supplements. Psychosocial factors, such as social disengagement and depressed mood, are associated with both poorer cognitive and emotional health in late life. Increased mental activity throughout life, such as learning new things, may also benefit brain health.
[296] Wagster, M., Hendrie H., Albert M., Butters M., Gao S., Knopman D. S., et al.
(2006). The NIH Cognitive and Emotional Health ProjectReport of the Critical Evaluation Study Committee.
Alzheimer's and Dementia. 2(1), 12 - 32.
http://www.eurekalert.org/pub_releases/2006-02/aa-nss021606.php
Fitness counteracts cognitive decline from hormone-replacement therapy
A study of 54 postmenopausal women (aged 58 to 80) suggests that being physically fit offsets cognitive declines attributed to long-term hormone-replacement therapy. It was found that gray matter in four regions (left and right prefrontal cortex, left parahippocampal gyrus and left subgenual cortex) was progressively reduced with longer hormone treatment, with the decline beginning after more than 10 years of treatment. Therapy shorter than 10 years was associated with increased tissue volume. Higher fitness scores were also associated with greater tissue volume. Those undergoing long-term hormone therapy had more modest declines in tissue loss if their fitness level was high. Higher fitness levels were also associated with greater prefrontal white matter regions and in the genu of the corpus callosum. The findings need to be replicated with a larger sample, but are in line with animal studies finding that estrogen and exercise have similar effects: both stimulate brain-derived neurotrophic factor.
[375] Erickson, K. I., Colcombe S. J., Elavsky S., McAuley E., Korol D. L., Scalf P. E., et al.
(2007). Interactive effects of fitness and hormone treatment on brain health in postmenopausal women.
Neurobiology of Aging. 28(2), 179 - 185.
http://www.eurekalert.org/pub_releases/2006-01/uoia-fcc012406.php
Lifestyle changes improve seniors’ memory surprisingly quickly
A small 14-day study found that those following a memory improvement plan that included memory training, a healthy diet, physical exercise, and stress reduction, showed a 5% decrease in brain metabolism in the dorsal lateral prefrontal region of the brain (involved in working memory) suggesting they were using their brain more efficiently. This change in activity was reflected in better performance on a cognitive measure controlled by this brain region, and participants reported that they felt their memory had improved. The memory training involved doing brainteasers, crossword puzzles and memory exercises. Diet involved eating 5 small meals daily (to prevent fluctuations in blood glucose levels) that were rich in omega-3 fats, low-glycemic index carbohydrates (e.g., whole grains) and antioxidants. Physical exercise involved brisk walking and stretching, and stress reduction involved stretching and relaxation exercises.
The study was presented at the American College of Neuropsychopharmacology's Annual Meeting on December 11-15, in Hawaii.
http://www.eurekalert.org/pub_releases/2005-12/g-nsf121205.php
Lifelong mild exercise decreases cellular aging in the brain
A rat study has provided evidence that regular, light exercise (say a daily 30-minute walk or a light 1-mile run) decreases cellular aging in the brain. Those rats who had had access to an exercise wheel during their lives showed fewer byproducts of oxidative stress in their brains, and their DNA at two years resembled that of their 6 month old counterparts.
The research was presented at the Society for Neuroscience's 35th annual meeting in Washington, D.C.
http://www.eurekalert.org/pub_releases/2005-11/uof-lea110905.php
Diet, exercise, stimulating environment helps old dogs learn
A new study of beagles provides more evidence that diet and mental stimulation are important in reducing or preventing age-related cognitive decline. The study, involving 48 older beagles (aged 7 to 11), compared four combinations of behavioral enrichment (regular exercise and lots of mental stimulation) and supplementation of diet with antioxidants had on a beagle's ability to learn: regular diet and regular experience; regular diet and enriched experience; regular experience and an enriched diet; and enriched diet and an enriched experience. The study followed the beagles over two years. Those in the groups with either an enriched diet or enriched environment did better than those without either, but those who had both the enriched diet and an enriched environment did noticeably better than all the rest.
[657] Milgram, N. W., Head E., Zicker S. C., Ikeda-Douglas C. J., Murphey H., Muggenburg B., et al.
(2005). Learning ability in aged beagle dogs is preserved by behavioral enrichment and dietary fortification: a two-year longitudinal study.
Neurobiology of Aging. 26(1), 77 - 90.
http://www.eurekalert.org/pub_releases/2005-01/uot-mtc011705.php
http://www.eurekalert.org/pub_releases/2005-01/nioa-des011805.php
Maintaining physical activity linked to less cognitive decline in older men
Longer and more intense physical activity may help people maintain their cognitive skills as they age, according to a 10-year study of 295 men, born between 1900 and 1920, from the Finland, Italy and Netherlands Elderly (FINE) Study. The study showed that over 10 years the cognitive decline in men who had reduced their daily physical activity by an hour or more was 2.6 times greater than the decline in men who maintained their activity. Men who performed their daily physical activity with a lower intensity 10 years later had a 3.6 times stronger decline than men who maintained the intensity level. Men who engaged in activities of the lowest intensity had up to 3.5 times greater decline than men who participated in activities with a higher intensity. There was no decline among those who increased the duration or intensity of their activities. Activities of medium-to-low intensity, such as walking three miles per day, was associated with less cognitive decline than the lowest-intensity activity like walking less than three miles per day.
van Gelder, B.M., Tijhuis, M.A.R., Kalmijn, S., Giampaoli, S., Nissinen, A. & Kromhout, D. 2004. Physical activity in relation to cognitive decline in elderly men: The FINE study. Neurology, 63, 2316-2321.
http://www.eurekalert.org/pub_releases/2004-12/aaon-mpa122104.php
Walking may protect elderly from dementia
A study of more than 2,200 Japanese-American men between the ages of 71 and 93 has found that elderly men who are sedentary or walk less than a quarter of a mile per day are nearly twice as likely to develop dementia and Alzheimer's disease compared to men who walk more than two miles per day. Those who walked less than a mile (and more than quarter of a mile) a day also showed a significantly greater risk of dementia than those walking more than two miles a day.
[327] Abbott, R. D., White L. R., Ross W. G., Masaki K. H., Curb D. J., & Petrovitch H.
(2004). Walking and Dementia in Physically Capable Elderly Men.
JAMA. 292(12), 1447 - 1453.
http://www.eurekalert.org/pub_releases/2004-09/uovh-wmp091504.php
Physical activity associated with better mental functioning in older women
Since 1986, 18,766 women, aged 70 to 81 years, have been questioned on their physical activity in biennial questionnaires. The women were divided into five groups depending on their average energy expenditures. Those in the highest activity grouping had a 20% lower risk of cognitive impairment than women in the lowest. Women who walked at an easy pace for at least 1.5 hours per week had higher cognitive scores than those who walked less than forty minutes per week.
[965] Weuve, J., Kang J H., Manson JA. E., Breteler M MB., Ware J. H., & Grodstein F.
(2004). Physical Activity, Including Walking, and Cognitive Function in Older Women.
JAMA. 292(12), 1454 - 1461.
http://www.eurekalert.org/pub_releases/2004-09/jaaj-pai091604.php
Music with exercise boosts mental performance
In the first study to look at the combined effects of music and short-term exercise on mental performance, researchers found that listening to music while exercising helped to increase scores on a verbal fluency test among cardiac rehabilitation patients. The study included 33 men and women in the final weeks of a cardiac rehabilitation program. Participants completed a verbal fluency test before and after two separate sessions of exercising on a treadmill. The workouts were scheduled a week apart and lasted about 30 minutes. Participants listened to classical music – Vivaldi's "The Four Seasons" – during one of the sessions. Participants reported feeling better emotionally and mentally after working out regardless of whether or not they listened to music. But the improvement in verbal fluency test performance after listening to music was more than double that of the non-music condition.
Emery, C.F., Hsiao, E.T., Hill, S.M. & Frid, D.J. 2003. Short-term effects of exercise and music on cognitive performance among participants in a cardiac rehabilitation program. Heart & Lung: The Journal of Acute and Critical Care, 32 (6), 368-373.
http://www.eurekalert.org/pub_releases/2004-03/osu-alm032304.php
Exercise improves attention and decision-making among seniors
An imaging study involving adults ranging in age from 58 to 78 before and after a six-month program of aerobic exercise, found specific functional differences in the middle-frontal and superior parietal regions of the brain that changed with improved aerobic fitness. Consistent with the functions of these brain regions, those who participated in the aerobic-exercise intervention significantly improved their performance on a computer-based decision-making task. Those doing toning and stretching exercises did increase activation in some areas of the brain but not in those tied to better performance. Their performance on the task was not significantly different after the exercise program. The aerobic exercise used in the study involved gradually increasing periods of walking over three months. For the final three months of the intervention program, each subject walked briskly for 45 minutes in three sessions each week.
[399] Elavsky, S., Colcombe S. J., Kramer A. F., Erickson K. I., Scalf P., McAuley E., et al.
(2004). Cardiovascular fitness, cortical plasticity, and aging.
Proceedings of the National Academy of Sciences of the United States of America. 101(9), 3316 - 3321.
http://www.eurekalert.org/pub_releases/2004-02/uoia-esf021104.php
High sugar blood levels linked to poor memory
A new study takes an important step in explaining cognitive impairment in diabetics, and suggests a possible cause for some age-related memory impairment. The study assessed non-diabetic middle-aged and elderly people. Those with impaired glucose tolerance (a pre-diabetic condition) had a smaller hippocampus and scored worse on tests for recent memory. These results were independent of age or overall cognitive performance. The brain uses glucose almost exclusively as a fuel source. The ability to get glucose from the blood is reduced in diabetes. The study raises the possibility that exercise and weight loss, which help control blood sugar levels, may be able to reverse some of the memory loss that accompanies aging.
[543] Convit, A., Wolf O. T., Tarshish C., & de Leon M. J.
(2003). Reduced glucose tolerance is associated with poor memory performance and hippocampal atrophy among normal elderly.
Proceedings of the National Academy of Sciences of the United States of America. 100(4), 2019 - 2022.
http://www.eurekalert.org/pub_releases/2003-02/nyum-hsb013003.php
Imaging study confirms link between exercise and cognitive function
A number of studies have suggested a link between exercise and cognitive function in older adults, but now an imaging study shows that there are actual anatomical differences in the brains of physically fit versus less fit older adults (over 55). Specifically, they found very distinct differences in the gray and white matter in the frontal, temporal, and parietal cortexes. With aging, these tissues shrink, a reduction closely matched by declines in cognitive performance. Fitness, it appears, slows that decline. A related study, published in March, suggests that women may benefit more from exercise than men.
Colcombe, S.J., Erickson, K.I., Raz, N., Webb, A.G., Cohen, N.J., McAuley, E. & Kramer, A.F. 2003. Aerobic Fitness Reduces Brain Tissue Loss in Aging Humans. Journal of Gerontology: Series A: Biological and Medical Sciences, 58, M176-M180.
http://www.eurekalert.org/pub_releases/2003-01/uoia-sif012703.php
Walking reduces cognitive decline in older women
A study that tested the cognitive abilities of 5,925 women who were 65 and older once and then again six to eight years later, found that the women who walked the least were most likely to develop cognitive decline -- 24 percent of them had significant declines in their test scores, compared to 17 percent of the most active group. The least active women walked an average of about a half mile per week, while the most active group walked an average of nearly 18 miles per week.
While any exercise appeared to be helpful, the benefit increased with every extra mile walked per week. Examples of activities that would reduce the risk of cognitive decline were: playing tennis twice a week, walking a mile per day, playing golf once a week.
The paper was presented by Kristine Yaffe at the American Academy of Neurology’s 53rd Annual Meeting in Philadelphia, May 5-11.
http://www.eurekalert.org/pub_releases/2001-05/AAoN-Wpwf-0805101.php
Aerobic exercise improves some mental processes in older adults
The team of Duke University Medical Center researchers who demonstrated in late 1999 that aerobic exercise is just as effective as medication in treating major depression in the middle-aged and elderly has now reported that the same exercise program also appears to improve the cognitive abilities of these patients. The researchers found significant improvements in the higher mental processes of memory and the so-called executive functions, which include planning, organization and the ability to mentally juggle different intellectual tasks at the same time. Attention and concentration did not appear to be affected. Because it has been theorised that a reduction in blood flow to the brain might be one of the reasons why the elderly – especially those with coronary artery disease or hypertension – might suffer some degree of cognitive decline, it is speculated that exercise might improve cognitive functioning in such patients by improving the flow of oxygen-rich blood to specific regions of the brain.
Khatri, P., Babyak, M., Herman, S., Baldewicz, T., Madden, D.J., Doraiswamy, ., Waugh, R., Krishnan, R. & Craighead, E. 2001. Effects of Exercise Training on Cognitive Functioning Among Depressed Older Men and Women. Journal of Aging and Physical Activity, 9 (1).
http://www.eurekalert.org/pub_releases/2001-01/DUMC-Aeic-1401101.php
124 previously sedentary adults, 60 to 75 years old, were randomly assigned to either aerobic (walking) or anaerobic (stretching and toning) exercise over a period of 6 months. Those who received aerobic training showed substantial improvements in performance on tasks requiring executive control (such as planning, scheduling, inhibition and working memory) compared with anaerobically trained subjects. Executive control processes are particularly affected by aging. The walking condition involved walking rapidly for 45 minutes three days a week.
Kramer, A.F., Hahn, S., Cohen, N.J., Banich, M.T., Mcauley, E., Harrison, C.R.,Chason, J., Vakil, E., Bardell, L., Boileau, R.A. & Colcombe, A. 1999. Ageing, fitness and neurocognitive function. Nature, 400, 418 - 419.
The benefits of physical exercise for cognitive and memory performance in the elderly have not been consistently demonstrated in research. This study, a longitudinal one (the Interdisciplinary Ageing (IDA) study), was designed to reduce perceived shortcomings of earlier research.
The 442 people ( 65 - 95 years old) involved in the study had had their medical data collected regularly since 1965. 46 volunteers from this group (18 women and 28 men; mean age73.2 years) participated in an eight-week resistance training program. The program involved a warm-up lasting 10 min, followed by eight resistance exercises on machines.
PParticipants displayed a significant increase in muscular strength directly after the training, and this was still significant one year later. However, there was no improvement in any subjective health ratings or psychological well-being measures, with the exception of a decrease inself-attentiveness (fewer self-centred thoughts; less anxiety about themselves and the future).
There was however a positive effect on cognitive function. Memory recall and recognition were both improved, and was still significant a year later. It is unlikely that this long-term improvement can be directly due to such a short-term physical training program, but perhaps the experience of mastering a new situation and changing established habits increased participants' motivation to seek new challenges. This openness and self-confidence could be responsible for participants staying physically, socially and mentally active and being self-reliant, all of which are prerequisites for optimal cognitive functioning.
Perrig-Chiello, P. 1998. The effects of resistance training on well-being and memory in elderly volunteers. Age and Ageing, 27
Dementia & MCI
Physical activity reduces MCI
A German study involving nearly 4000 older adults (55+) has found that physical activity significantly reduced the risk of developing mild cognitive impairment over a two-year period. Nearly 14% of those with no physical activity at the start of the study developed cognitive impairment, compared to 6.7% of those with moderate activity, and 5.1% of those with high activity. Moderate activity was defined as less than 3 times a week.
[248] Etgen, T., Sander D., Huntgeburth U., Poppert H., Forstl H., & Bickel H.
(2010). Physical Activity and Incident Cognitive Impairment in Elderly Persons: The INVADE Study.
Arch Intern Med. 170(2), 186 - 193.
http://www.eurekalert.org/pub_releases/2010-01/jaaj-paa012110.php
Exercise and Mediterranean-type diet associated with lower risk for Alzheimer's
A New York study involving 1880 elderly (average age 77) is the first to investigate both exercise and diet in connection with the later development of Alzheimer’s (within a five and a half year period). Participants were asked about their activity in the two weeks prior to the interview, about the regularity and duration, as well as the quality (vigorous, moderate, light). They were also asked about their food consumption over the previous year, and their responses grouped into nine food categories, the sum of which represented a Mediterranean-type diet score. Those who were very physically active had a 33% risk reduction of Alzheimer's; those who adhered more strongly to a Mediterranean-type diet had a 40% risk reduction. Those who did both had a 60% reduction. A Mediterranean-type diet is typically characterized by high intake of fish, vegetables, legumes, fruits, cereals and monounsaturated fatty acids; relatively low intake of dairy products, meats and saturated fats; and moderate alcohol consumption.
Scarmeas, N. et al. 2009. Physical Activity, Diet, and Risk of Alzheimer Disease. Journal of the American Medical Association, 302(6), 627-637.
Full text available at http://jama.ama-assn.org/cgi/content/full/302/6/627?home
http://www.eurekalert.org/pub_releases/2009-08/cumc-eam080609.php
Moderate exercise helps mild cognitive impairment
An Australian study involving 138 older adults (50 years and over) with mild cognitive impairment, has found that those who undertook to achieve 2 ½ hours of physical activity each week (three 50 minute sessions), ranging from walking, ballroom dancing to swimming, for a six month period, continually out-scored the control group on cognitive tests during the 18 month testing period — showing that memory improvement was still evident a year after the supervised exercise period.
[1212] Lautenschlager, N. T., Cox K. L., Flicker L., Foster J. K., van Bockxmeer F. M., Xiao J., et al.
(2008). Effect of Physical Activity on Cognitive Function in Older Adults at Risk for Alzheimer Disease: A Randomized Trial.
JAMA. 300(9), 1027 - 1037.
http://www.eurekalert.org/pub_releases/2008-09/ra-wtp090108.php
http://www.eurekalert.org/pub_releases/2008-09/uom-aow090108.php
http://www.eurekalert.org/pub_releases/2008-09/jaaj-emh082808.php
Exercise may slow brain shrinkage in early Alzheimer's
A study of 121 people age 60 and older, of whom 57 were in the early stages of Alzheimer's disease, has found that those with early Alzheimer's disease who were less physically fit (measured by cardiorespiratory fitness) had four times more brain shrinkage when compared to normal older adults than those who were more physically fit. The findings suggest the value of physical fitness in slowing down the progression of Alzheimer's disease. The association existed even after age, gender, severity of dementia, physical activity and frailty were accounted for. There was no relationship between higher fitness levels and brain changes in the group of people without dementia.
Burns, J.M. et al. 2008. Cardiorespiratory fitness and brain atrophy in early Alzheimer disease. Neurology, 71, 210-216.
http://www.eurekalert.org/pub_releases/2008-07/aaon-emp070808.php
Mental and physical exercise delays dementia
A study using genetically engineered mice has found providing the mice with an enriched environment that enhanced their mental and physical stimulation improved performance on memory tests at an early stage of Huntington's disease, when memory impairment has begun. Specific molecular changes were also observed at the synapses in the hippocampus. Those without increased mental and physical activity showed decreased levels of specific proteins that are expressed at the synapse, but those exposed to stimulation didn’t. The finding offers hope for slowing the progression of the disease, as well as other dementias.
Nithianantharajah, J., Barkus, C., Murphy, M. & Hannan, A.J. Gene–environment interactions modulating cognitive function and molecular correlates of synaptic plasticity in Huntington’s disease transgenic mice. Neurobiology of Disease, Published online ahead of print 24 November 2007
http://www.eurekalert.org/pub_releases/2008-01/ra-map012308.php
Walking and moderate exercise help prevent dementia
A four-year study involving 749 older adults has found that the top one-third of participants who exerted the most energy in moderate activities such as walking were significantly less likely to develop vascular dementia than those people in the bottom one-third of the group. Contrary to some reports, no such association was found with Alzheimer’s disease.
Ravaglia, G. et al. 2007. Physical activity and dementia risk in the elderly. Findings from a prospective Italian study. Neurology, published online ahead of print December 19
http://www.eurekalert.org/pub_releases/2007-12/aaon-wam121107.php
How mental and physical stimulation slows Alzheimer's
A new study reveals how mental and physical activity slows the cognitive decline seen in Alzheimer’s. In the study, genetically engineered mice were housed in either standard cages or ones with access to an enriched environment. After five months, the mice housed in the enriched environment had fewer Ab plaques, smaller plaque size, and reduced amyloid angiopathy compared to mice housed in standard cages. However there were no differences in the levels of soluble Ab peptide or the expression levels of its precursor protein (APP). Further investigation revealed differences suggesting that an enriched environment elicits protection via pathways that prevent Ab accumulation and enhance its clearance. The data confirm that an environment rich in mental and physical stimulation slows the progression of Alzheimer-like brain pathology.
Ambrée, O. et al. 2006. Reduction of amyloid angiopathy and A² plaque burden after enriched housing in TgCRND8 mice: involvement of multiple pathways. American Journal of Pathology, 169, 544-552.
http://www.sciencedaily.com/releases/2006/07/060724002331.php
Good physical function linked to Alzheimer's delay
A study following 2,288 older adults for six years found that those whose physical function was higher at the start of the study were three times less likely to develop dementia than were those whose physical function was lower.
Wang, L., Larson, E.B., Bowen, J.D. & van Belle, G. 2006. Performance-Based Physical Function and Future Dementia in Older People. Archives of Internal Medicine, 166, 1115-1120.
http://www.eurekalert.org/pub_releases/2006-05/ghcc-gpf051806.php
Exercise protects against Alzheimer's
A study following 1,740 seniors (aged 65 and older) over a six-year period, found that those who exercised three or more times a week had a 30 — 40% lower risk for developing dementia compared with those who exercised fewer than three times per week. Even modest amounts, such as walking 15 minutes a day, appear beneficial, and the more frail the person was, the more they benefited from regular exercise.
Larson, E.B., Wang, L., Bowen, J.D., McCormick, W.C., Teri, L., Crane, P., & Kukull, W. 2006. Exercise Is Associated with Reduced Risk for Incident Dementia among Persons 65 Years of Age and Older. Annals of Internal Medicine, 144 (2), 73-81.
http://www.eurekalert.org/pub_releases/2006-01/ghcc-eil011006.php
Exercise slows development of Alzheimer's-like brain changes in mice
Population-based studies have provided evidence that various lifestyle interventions might help slow the onset and progression of Alzheimer’s. A mouse study now provides a clue how that might work. Physical activity enhanced the learning ability of mice genetically engineered to develop amyloid plaques and decreased the level of plaque-forming beta-amyloid protein fragments in their brains. The mice were divided into mice with access to running wheels or no access. The findings are supported by another recent study that found that beta-amyloid levels decreased in the brains of another kind of transgenic mice when they were housed in groups and in environments that were enriched with running wheels, colored tunnels, and toys.
Adlard, P.A., Perreau, V.M., Pop, V. & Cotman, C.W. 2005. Voluntary Exercise Decreases Amyloid Load in a Transgenic Model of Alzheimer's Disease. Journal of Neuroscience, 25, 4217-4221.
http://www.eurekalert.org/pub_releases/2005-04/nioa-esd042605.php
Enriched environment delays onset of Alzheimer's in mice
A study of genetically engineered mice has found that an enriched environment, with more opportunities to exercise, explore and interact with others, can dramatically reduce levels of beta-amyloid peptides, hallmarks of Alzheimer's disease. The mice also showed greater activity for several genes involved in memory and learning, the growth of new nerve cells, cell survival, and the growth of new blood vessels within the brain. As with humans, mice in the enriched environment showed varying levels of activity. The most active were found to have the least beta-amyloid. Researchers suggested the reason may simply be a matter of blood flow; physical and mental activity can stimulate growth of new blood vessels and keep existing vessels open and functional.
Lazarov, O.et al. 2005. Environmental Enrichment Reduces Aβ Levels and Amyloid Deposition in Transgenic Mice. Cell, 120(5), 701-713.
http://www.eurekalert.org/pub_releases/2005-03/uocm-eed030705.php
Why diet, hormones, exercise might delay Alzheimer’s
A theory that changes in fat metabolism in the membranes of nerve cells play a role in Alzheimer's has been supported in a recent study. The study found significantly higher levels of ceramide and cholesterol in the middle frontal gyrus of Alzheimer's patients. The researchers suggest that alterations in fats (especially cholesterol and ceramide) may contribute to a "neurodegenerative cascade" that destroys neurons in Alzheimer's, and that the accumulation of ceramide and cholesterol is triggered by the oxidative stress brought on by the presence of the toxic beta amyloid peptide. The study also suggests a reason for why antioxidants such as vitamin E might delay the onset of Alzheimer's: treatment with Vitamin E reduced the levels of ceramide and cholesterol, resulting in "a significant decrease in the number of neurons killed by the beta amyloid and oxidative stress.
Cutler, R.G., Kelly, J., Storie, K., Pedersen, W.A., Tammara, A., Hatanpaa, K., Troncoso, J.C. & Mattson, M.P. 2004. Involvement of oxidative stress-induced abnormalities in ceramide and cholesterol metabolism in brain aging and Alzheimer's disease. PNAS, 101, 2070-5.
http://www.eurekalert.org/pub_releases/2004-02/aaft-nsm021004.php
Children & young adults
Aerobic fitness boosts IQ in teenage boys
Data from the 1.2 million Swedish men born between 1950 and 1976 who enlisted for mandatory military service at the age of 18 has revealed that on every measure of cognitive performance, average test scores increased according to aerobic fitness — but not muscle strength. The link was strongest for logical thinking and verbal comprehension, and the association was restricted to cardiovascular fitness. The results of the study also underline the importance of getting healthier between the ages of 15 and 18 while the brain is still changing — those who improved their cardiovascular health between 15 and 18 showed significantly greater intelligence scores than those who became less healthy over the same time period. Those who were fittest at 18 were also more likely to go to college. Although association doesn’t prove cause, the fact that the association was only with cardiovascular fitness and not strength supports a cardiovascular effect on brain function. Results from over 260,000 full-sibling pairs, over 3,000 sets of twins, and more than 1,400 sets of identical twins, also supports a causal relationship.
[819] Kuhn, H. G., Aberg M. A. I., Pedersen N. L., Toren K., Svartengren M., Backstrand B., et al.
(2009). Cardiovascular fitness is associated with cognition in young adulthood.
Proceedings of the National Academy of Sciences. 106(49), 20906 - 20911.
http://www.physorg.com/news179415275.html
http://www.telegraph.co.uk/science/science-news/6692474/Physical-health-leads-to-mental-health.html
Vigorous exercise helps children's grades
214 sixth graders were divided into two groups — one group took a general physical education class in the first semester, then a non-physical education course in the next semester. The other group did the classes in the other order. There was no difference in performance in academic classes between those taking the physical education course and those taking the non-physical. However, students who took part in more vigorous physical activities at least three times a week (such as soccer, skateboarding) did better in academic subjects (by around 10%). It’s worth noting that PE classes only averaged 19 minutes of moderate or vigorous activity; activity outside the classroom was assessed in 30 minute blocks. Only vigorous activity impacted academic performance.
[728] Coe, D P., Pivarnik J. M., Womack C. J., Reeves M. J., & Malina R. M.
(2006). Effect of physical education and activity levels on academic achievement in children.
Medicine and Science in Sports and Exercise. 38(8), 1515 - 1519.
http://www.sciencedaily.com/releases/2006/08/060803181914.php
Physically fit children appear to do better in classroom
Several studies in recent years have demonstrated that exercise may improve cognitive functioning in older adults. New research suggests the same may be true of children. Preliminary results from a series of studies over the past two years have found a strong relationship between academic achievement and fitness scores. One of these studies also found that fit children were faster and more accurate at a visual discrimination task than sedentary children.
The study was presented at the annual meeting of the Society for Psychophysiological Research in Santa Fe, N.M., Oct. 20-24.
http://www.eurekalert.org/pub_releases/2004-10/uoia-pfc101904.php
Lack of benefit
Whether lifelong physical activity helps or hurts the aging brain depends on extent
A study of 90 post-menopausal women found that long-term strenuous activity was consistently associated with poorer performance on all eight cognitive tests, in particular tests of semantic memory, working memory, delayed verbal recall, and sustained attention. However, moderate physical activity was consistently associated with better performance on all eight of the tests, especially cognitive flexibility, working memory, and sustained attention.
Tierney, M.C. et al. 2009. Intensity of long-term physical activity and later life cognition in postmenopausal women. Presented at the Alzheimer's Association International Conference on Alzheimer's Disease July 11-16 in Vienna.
http://www.eurekalert.org/pub_releases/2009-07/aa-ah070209.php
Alzheimer's Gene May Reduce Benefits of Physical Activity for Cognitive Ability
A study of some 1800 seniors (60+) found that the association of physical activity with better cognitive function was significant only for those who didn’t carry any copies of the “Alzheimer’s gene” APOE-e4 (which is the majority of people), and was greater with age.
Obisesan, T.O., Hamilton, J. & Gillum, R.F. 2009. Aerobic-related physical activity interacting with apolipoprotein E genotypes, is associated with better cognitive function in a nationally representative sample: The Third National Health and Nutrition Examination Survey (NHANES III). Presented at the Alzheimer's Association International Conference on Alzheimer's Disease July 11-16 in Vienna.
http://www.eurekalert.org/pub_releases/2009-07/aa-ah070209.php
Some people are 'immune' to exercise
In view of the apparent benefits of exercise for cognitive function suggested by recent research, it is worth noting that a study involving 742 people from 213 families has found that "There is astounding variation in the response to exercise. The vast majority will benefit in some way, but there will be a minority who will not benefit at all."
The results were reported at the Australian Health and Medical Research Congress in Sydney, Australia.
http://www.newscientist.com/news/news.jsp?id=ns99996735
