Stress raises risk of mental decline in older diabetics

Here’s an exciting little study, implying as it does that one particular aspect of information processing underlies much of the cognitive decline in older adults, and that this can be improved through training. No, it’s not our usual suspect, working memory, it’s something far less obvious: temporal processing.

Back in 2009, I reported briefly on a large Norwegian study that found that older adults who consumed chocolate, wine, and tea performed significantly better on cognitive tests. The association was assumed to be linked to the flavanols in these products. A new study confirms this finding, and extends it to older adults with mild cognitive impairment.

My recent reports on brain training for older adults (see, e.g., Review of working memory training programs finds no broader benefit; Cognitive training shown to help healthy older adults; Video game training benefits cognition in some older adults) converge on the idea that cognitive training can indeed be beneficial for older adults’

A review of three high quality trials comparing the putative benefits of omega-3 fatty acids for preventing age-related cognitive decline, has concluded that there is no evidence that taking fish oil supplements helps fight cognitive decline. The trials involved a total of 3,536 healthy older adults (60+). In two studies, participants were randomly assigned to receive gel capsules containing omega-3 PUFA or olive or sunflower oil for six or 24 months.

The latest finding from the large, long-running Health, Aging, and Body Composition (Health ABC) Study adds to the evidence that preventing or controlling diabetes helps prevent age-related cognitive decline.

A study designed to compare the relative benefits of exercise and diet control on Alzheimer’s pathology and cognitive performance has revealed that while both are beneficial, exercise is of greater benefit in reducing Alzheimer’s pathology and cognitive impairment.

I often talk about the importance of attitudes and beliefs for memory and cognition. A new honey bee study provides support for this in relation to the effects of aging on the brain, and suggests that this principle extends across the animal kingdom.

While the ‘Alzheimer’s gene’ is relatively common — the ApoE4 mutation is present in around 15% of the population — having two copies of the mutation is, thankfully, much rarer, at around 2%. Having two copies is of course a major risk factor for developing Alzheimer’s, and it has been thought that having a single copy is also a significant (though lesser) risk factor. Certainly there is quite a lot of evidence linking ApoE4 carriers to various markers of cognitive impairment.

The study involved 120 healthy older adults (60-79) from Shanghai, who were randomly assigned to one of four groups: one that participated in three sessions of tai chi every week for 40 weeks; another that instead had ‘social interaction’ sessions (‘lively discussions’); another in which participants engaged in walking around a track; and a non-intervention group included as a control. Brain scans were taken before and after the 40-week intervention, and cognitive testing took place at 20 weeks as well as these times.

I have reported previously on research suggesting that rapamycin, a bacterial product first isolated from soil on Easter Island and used to help transplant patients prevent organ rejection, might improve learning and memory. Following on from this research, a new mouse study has extended these findings by adding rapamycin to the diet of healthy mice throughout their life span. Excitingly, it found that cognition was improved in young mice, and abolished normal cognitive decline in older mice.