Another study adds to the growing evidence that a Mediterranean diet is good for the aging brain.
The New York study used data from 674 non-demented older adults (average age 80). It found that those who closely followed such a diet showed significantly less brain shrinkage. Specifically, total brain volume was an average 13.11 milliliters greater, with grey matter volume 5 millilitres greater, and white matter 6.4 millilitres greater.
A two-year study which involved metabolic testing of 50 people, suggests that Alzheimer's disease consists of three distinct subtypes, each one of which may need to be treated differently. The finding may help explain why it has been so hard to find effective treatments for the disease.
The subtypes are:
A study involving both mice and human cells adds to evidence that stress is a risk factor for Alzheimer's.
The study found that mice who were subjected to acute stress had more amyloid-beta protein in their brains than a control group. Moreover, they had more of a specific form of the protein, one that has a particularly pernicious role in the development of Alzheimer's disease.
When human neurons were treated with the stress hormone corticotrophin releasing factor (CRF), there was also a significant increase in the amyloid proteins.
Data from 23,572 Americans from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study has revealed that those who survived a stroke went on to have significantly faster rates of cognitive decline as they aged.
Participants, who were aged 45 years or older, had no history of cognitive impairment at the beginning of the population-based study. Over the next five to seven years, 515 of them (2%) had a stroke.
A study involving 382 older adults (average age 75) followed for around five years, has found that those who don’t get enough vitamin D may experience cognitive decline at a much faster rate than people who have adequate vitamin D.
Participants included 17.5% with dementia at the beginning of the study, 32.7% with MCI, and 49.5% cognitively healthy.
Those with dementia had lower levels of vitamin D than the other two groups.
Training in a mental imagery technique has been found to help multiple sclerosis patients in two memory domains often affected by the disease: autobiographical memory and episodic future thinking.
A study involving 218 participants aged 18-88 has looked at the effects of age on the brain activity of participants viewing an edited version of a 1961 Hitchcock TV episode (given that participants viewed the movie while in a MRI machine, the 25 minute episode was condensed to 8 minutes).
While many studies have looked at how age changes brain function, the stimuli used have typically been quite simple. This thriller-type story provides more complex and naturalistic stimuli.
A study involving 100 healthy older adults (aged 60-80) has found that those with higher levels of physical activity showed more variable spontaneous brain activity in certain brain regions (including the precuneus, hippocampus, medial and lateral prefrontal, and temporal cortices). Moreover, this relationship was positively associated with better white-matter structure.
Higher rates of activity when the brain is “at rest” have previously been shown to be associated with better cognitive performance in older adults, especially in IQ and memory.
A ten-year study involving 2,092 older adults (average age 76) has found that people tended to lose awareness of memory problems two to three years before the onset of dementia.
Being unaware of your own memory problems is common in dementia, but previous research has focused on those already diagnosed with dementia. In this study, participants had no cognitive impairment at the beginning of the study.
A large, five-year study challenges the idea that omega-3 fatty acids can slow age-related cognitive decline. The study, involving 4,000 older adults, was part of the Age-Related Eye Disease Study (AREDS), which established that daily high doses of certain antioxidants and minerals can help slow the progression of age-related macular degeneration. However, a follow-up study found the addition of omega-3 fatty acids to the AREDS formula made no difference.