aging

A number of studies have found evidence that fruits and vegetables help fight age-related cognitive decline, and this has been thought to be due to their antioxidant and anti-inflammatory effects. A new study shows there may be an additional reason why polyphenols benefit the aging brain. One reason why the brain works less effectively as it gets older is that the cells (microglia) that remove and recycle biochemical debris not only fail to do their housekeeping work, but they actually begin to damage healthy cells.

I have often spoken of the mantra: What’s good for your heart is good for your brain. The links between cardiovascular risk factors and cognitive decline gets more confirmation in this latest finding that people whose hearts pumped less blood had smaller brains than those whose hearts pumped more blood. The study involved 1,504 participants of the decades-long Framingham Offspring Cohort who did not have a history of stroke, transient ischemic attack or dementia. Participants were 34 to 84 years old.

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.

A very large study of older women has found that although there was a small downward trend in cognitive function (as measured by the MMSE) with increasing obesity, this trend was almost entirely driven by those with a waist-hip ratio below 0.78 — that is, for women who carry excess weight around their hips, known as pear shapes (as opposed to carrying it around the waist, called apple shapes).

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.

While brain training programs can certainly improve your ability to do the task you’re practicing, there has been little evidence that this transfers to other tasks. In particular, the holy grail has been very broad transfer, through improvement in working memory. While there has been some evidence of this in pilot programs for children with ADHD, a new study is the first to show such improvement in older adults using a commercial brain training program.

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.

A rat study demonstrates how specialized brain training can reverse many aspects of normal age-related cognitive decline in targeted areas. The month-long study involved daily hour-long sessions of intense auditory training targeted at the primary auditory cortex. The rats were rewarded for picking out the oddball note in a rapid sequence of six notes (five of them of the same pitch). The difference between the oddball note and the others became progressively smaller. After the training, aged rats showed substantial reversal of their previously degraded ability to process sound.

Another study has come out showing that older adults with low levels of vitamin D are more likely to have cognitive problems. The six-year study followed 858 adults who were age 65 or older at the beginning of the study. Those who were severely deficient in vitamin D were 60% more likely to have substantial cognitive decline, and 31% more likely to have specific declines in executive function, although there was no association with attention.

Subjective cognitive impairment (SCI), marked by situations such as when a person recognizes they can't remember a name like they used to or where they recently placed important objects the way they used to, is experienced by between one-quarter and one-half of the population over the age of 65. A seven-year study involving 213 adults (mean age 67) has found that healthy older adults reporting SCI are dramatically more likely to progress to MCI or dementia than those free of SCI (54% vs 15%). Moreover, those who had SCI declined significantly faster.