A study involving 65 older adults (59-80), who were very sedentary before the study (reporting less than two episodes of physical activity lasting 30 minutes or more in the previous six months), has found that those who joined a walking group improved their cognitive performance and the connectivity in important brain circuits after a year. However, those who joined a stretching and toning group showed no such improvement. The walking program involved three 40-minute walks at a moderate pace every week. The two affected brain circuits (the default mode network and the fronto-executive network) typically become less connected with age. It is worth emphasizing that the improvement was not evident at the first test, after six months, but only at the second 12-month test.

Interestingly, I noticed in the same journal issue a study into the long-term benefits of dancing for older adults. The study compared physical and cognitive performance of those who had engaged in amateur dancing for many years (average: 16.5 years) and those with no dancing or sporting engagement. The dancing group were overall significantly better than the other group on all tests: posture, balance, reaction time, motor behavior, cognitive performance. However, the best dancers weren’t any better than individuals in the other group; the group difference arose because none of the dancers performed poorly, while many of the other group did.

Following on from previous research with mice that demonstrated that a diet rich in methionine could increase the risk of developing Alzheimer's Disease through its effect on homocysteine levels, a new study has found that these effects were reversible if the mice then switched to a healthier diet. The mice, after five months on a methionine-rich diet, were divided into two groups, with one group continuing the diet and the second switching to the healthy diet for an additional two months. The cognitive impairment, and the build-up in amyloid plaques, was completely reversed after two months.

Methionine is an amino acid typically found in red meats, fish, beans, eggs, garlic, lentils, onions, yogurt and seeds. I note, however, that most of the items in this list are usually considered healthy! Fish, in particular, has been shown in a number of studies to reduce the risk of Alzheimer’s. The point is that methionine in itself is an essential amino acid and necessary for a healthy brain, but this indicates that, as with many foods, moderation is important. Clearly a balance is required; equally clearly, we still haven’t quite worked out the ‘perfect’ Alzheimer’s-prevention diet. Nevertheless, this study is welcome in demonstrating that diet can have such an effect on the brain, and adds to our knowledge of what makes a good diet for staving off dementia.

A small study suggests that the apathy shown by many Alzheimer's patients may not simply be due to memory or language problems, but to a decreased ability to experience emotions. The seven patients were asked to rate pictures of positive and negative scenes (such as babies and spiders) by putting a mark closer or further to either a happy face or a sad face emoticon. Closeness to the face indicated the strength of the emotion felt. Although most of the time the Alzheimer’s patients placed their mark in the appropriate direction, they did make more inappropriate choices than the control group, and typically also gave less intense judgments.

Both comprehension problems and depression were ruled out. A lower emotional response may result from damage to brain areas that produce neurotransmitters, which typically occurs early in Alzheimer’s. It may be that medication to replace or increase these neurotransmitters would improve emotional experience.

This finding is a warning that apathy should not be automatically taken to mean that the patient is depressed. The researchers, enabled by the small size of the study, tested more thoroughly for depression than is usually the case in large studies. It may be that in these studies, this apathy has often been confounded with depression — which may explain the inconsistencies in the research into depression and Alzheimer’s (see the news item just previous to this).

The finding may also help caregivers understand that any emotional indifference is not ‘personal’.

Anticholinergics are widely used for a variety of common medical conditions including insomnia, allergies, or incontinence, and many are sold over the counter. Now a large six-year study of older African-Americans has found that taking one anticholinergic significantly increased an individual's risk of developing mild cognitive impairment and taking two of these drugs doubled this risk. The risk was greater for those who didn’t have the ‘Alzheimer’s gene’, APOE-e4.

This class of drugs includes Benadryl®, Dramamine®, Excedrin PM®, Nytol®, Sominex®, Tylenol PM®, Unisom®, Paxil®, Detrol®, Demerol® and Elavil® (for a more complete list of medications with anticholinergic effects, go to http://www.indydiscoverynetwork.org/AnticholienrgicCognitiveBurdenScale....).

A review of the many recent studies into the effects of music training on the nervous system strongly suggests that the neural connections made during musical training also prime the brain for other aspects of human communication, including learning. It’s suggested that actively engaging with musical sounds not only helps the plasticity of the brain, but also helps provide a stable scaffolding of meaningful patterns. Playing an instrument primes the brain to choose what is relevant in a complex situation. Moreover, it trains the brain to make associations between complex sounds and their meaning — something that is also important in language. Music training can provide skills that enable speech to be better heard against background noise — useful not only for those with some hearing impairment (it’s a common difficulty as we get older), but also for children with learning disorders. The review concludes that music training tones the brain for auditory fitness, analogous to the way physical exercise tones the body, and that the evidence justifies serious investment in music training in schools.