Part of the Women's Health Initiative study looking at the effect of hormone therapy on thinking and memory in postmenopausal women, involving over 1400 women, has found those who had high blood pressure at the start of the study (eight years earlier) had significantly higher amounts of white matter lesions. Damage to white matter seems to be an independent risk factor for dementia. The finding adds to evidence suggesting that preventing hypertension helps protect against dementia. High blood pressure is common in the U.S.
Latest Research News
A study (“Midlife in the United States”) assessing 3,343 men and women aged 32-84 (mean age 56), of whom almost 40% had at least a 4-year college degree, has found evidence that frequent cognitive activity can counteract the detrimental effect of poor education on age-related cognitive decline.
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.
A rat study has found that increased levels of magnesium in the brain improved many aspects of learning and memory in both young and old rats. Because it is difficult to boost brain magnesium levels with traditional oral supplements, the researchers developed a new magnesium compound, magnesium-L-threonate (MgT). The cognitive improvements were associated with an increase in synapses and improved synaptic plasticity.
No surprise to me (I’m hopeless at faces), but a twin study has found that face recognition is heritable, and that it is inherited separately from IQ. The findings provide support for a modular concept of the brain, suggesting that some cognitive abilities, like face recognition, are shaped by specialist genes rather than generalist genes. The study used 102 pairs of identical twins and 71 pairs of fraternal twins aged 7 to 19 from Beijing schools to calculate that 39% of the variance between individuals on a face recognition task is attributable to genetic effects.
It’s been suggested before that Down syndrome and Alzheimer's are connected. Similarly, there has been evidence for connections between diabetes and Alzheimer’s, and cardiovascular disease and Alzheimer’s. Now new evidence shows that all of these share a common disease mechanism. According to animal and cell-culture studies, it seems all Alzheimer's disease patients harbor some cells with three copies of chromosome 21, known as trisomy 21, instead of the usual two. Trisomy 21 is characteristic of all the cells in people with Down syndrome.
Consistent with studies showing that gender stereotypes can worsen math performance in females, a year-long study involving 17 first- and second-grade teachers and their 52 boy and 65 girl students has found that boys' math performance was not related to their (female) teacher's math anxiety while girls' math achievement was. Early elementary school teachers in the United States are almost exclusively female. Math achievement was unrelated to teacher math anxiety in both boys and girls at the beginning of the school year.
A European trial involving 225 patients with mild Alzheimer's has found that those who drank Souvenaid (a cocktail of uridine, choline and the omega-3 fatty acid DHA, plus B vitamins, phosopholipids and antioxidants) for 12 weeks were more likely to improve their performance in a delayed verbal recall task. 40% of the Souvenaid group showed improved performance compared to 24% of the placebo group. Those with the mildest cases of Alzheimer’s showed the most improvement. There was no improvement on the more general ADAS-cog test. Three further clinical trials, one in the U.S.
A mouse study has found that the diet of a pregnant mother, especially in regards to choline, can change the epigenetic switches that control brain development in the fetus. Pregnant mice received different diets during the period when a fetus develops its hippocampus. The genetic changes affected neurogenesis. The findings add to other research pointing to the effects of maternal diet on fetal development. Top sources of choline are eggs and meat. Fish and soy are also good sources.
‘Working memory’ is thought to consist of three components: one concerned with auditory-verbal processing, one with visual-spatial processing, and a central executive that controls both. It has been hypothesized that the relationships between the components changes as children develop. Very young children are more reliant on visuospatial processing, but later the auditory-verbal module becomes more dominant. It has also been found that the two sensory modules are not strongly associated in younger (5-8) American children, but are strongly associated in older children (9-12).