The role of the catechol-O-methyltransferase (COMT) gene in cognitive function has been the subject of some debate. The gene, which affects dopamine, comes in two flavors: Val and Met. One recent study found no difference between healthy carriers of these two gene variants in terms of cognitive performance, but did find differences in terms of neural activity. Another found that, although the gene did not affect Alzheimer’s risk in its own, it acted synergistically with the Alzheimer’s gene variant to do so. Now an eight-year study of nearly 3000 adults in their 70s has revealed that the Met variant of the COMT gene was linked to a greater decline in cognitive function. This effect was more pronounced for African-Americans. This is interesting because it has been the Val genotype that in other research has been shown to have a detrimental effect. It seems likely that this genotype must be considered in its context (age, race, gender, and ApoE status have all been implicated in research).
Gene variant may protect memory and thinking skills in older people
Reference
Fiocco, A. J., Lindquist, K., Ferrell, R., Li, R., Simonsick, E., Nalls, M., … Study, F. the H. A. (2010). COMT genotype and cognitive function: An 8-year longitudinal study in white and black elders. Neurology, 74(16), 1296-1302. Retrieved from http://www.neurology.org/cgi/content/abstract/74/16/1296
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Does mental stimulation help fight age-related cognitive decline?
Can computer use, crafts and games slow or prevent age-related memory loss?
A study involving 2,000 healthy older adults (average age 78) found that mentally stimulating activities were linked to a lower risk or delay of MCI, and that the timing and number of these activities may also play a role.
During the study, 532 participants developed MCI.
Age differences in the allocation of study time
Journal Article
Dunlosky, J. & Connor, L.T. (1997). Age differences in the allocation of study time account for age differences in memory performance. Memory and Cognition, 25, 691-700.
- It is well-established that older adults commonly need to practice more than younger adults to achieve the same level of performance.
- It may be that such age deficits in remembering are at least partly due to poorer monitoring of their learning.
It has been well-established that, compared to younger adults, older adults require more practice to achieve the same level of performance1. Sometimes, indeed, they may need twice as much2.
In the present study, two groups of adult subjects were given paired items to learn during multiple study-test trials. During each trial items were presented at the subject's pace. Afterwards the subjects were asked to judge how likely they were to be able to recall each item in a test.
It was found that people were very good at accurately judging the likelihood of their correct recall. Correlations between judgments and the amount of time the subjects studied the items suggested that people were monitoring their learning and using this to allocate study time.
However, older adults (with a mean age of 67) used monitoring to a lesser degree than the younger adults (with a mean age of 22), and the results suggested that part of the reason for the deficit in recall commonly found with older adults is due to this factor.
References
1. For a review, see Kausler, D.H. 1994. Learning and memory in normal aging. New York: Academic Press.
2. Delbecq-Derousné, J. & Beauvois, M. 1989. Memory processes and aging: A defect of automatic rather than controlled processes? Archives of Gerontology & Geriatrics, 1 (Suppl), 121-150.
Salthouse, T.A. & Dunlosky, J. 1995. Analyses of adult age differences in associative learning. Zeitschrift für Psychologie, 203, 351-360
Distinguishing normal cognitive decline from more serious disorders
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Data from two longitudinal studies of older adults (a nationally representative sample of older adults, and the Alzheimer’s Disease Neuroimaging Initiative) has found that a brief cognitive test can distinguish memory decline associated with healthy aging from more serious memory disorders, years before obvious symptoms show up.
Moreover, the data challenge the idea that memory continues to decline through old age: after excluding the cognitively impaired, there was no evidence of further memory declines after the age of 69.
One Alzheimer's risk gene may begin to affect brains from childhood
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A gene linked to Alzheimer's has been linked to brain changes in childhood. This gene, SORL1, has two connections to Alzheimer’s: it carries the code for the sortilin-like receptor, which is involved in recycling some molecules before they develop into amyloid-beta; it is also involved in lipid metabolism, putting it at the heart of the vascular risk pathway.
Daily crosswords linked to sharper brain in later life
Data from more than 17,000 healthy people aged 50 and over has revealed that the more regularly participants engaged with word puzzles, the better they performed on tasks assessing attention, reasoning and memory.
Study participants took part in online cognitive tests, as well as being asked how frequently they did word puzzles such as crosswords. There was a direct relationship between the frequency of word puzzle use and the speed and accuracy of performance on nine cognitive tasks.
Sleep problems linked to age-related cognitive problems
Chronic insomnia linked to memory problems
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What causes word finding failures in young and older adults
Journal Article
Burke, D.M., MacKay, D.G., Worthley, J.S. & Wade, E. (1991). On the tip of the tongue: What causes word finding failures in young and older adults. Journal of Memory and Language, 30, 542-579.
- Failing to immediately retrieve well-known information does become more common with age.
- An increase in "tips of the tongue" is evident as early as the mid-thirties.
- The increase in memory failures applies to names of people and things; abstract words do not get harder to recall.
- The length of time before the missing word is recalled also increases with age.
- Older people tend to be less likely than younger people to actively pursue a missing word.
It is common for people to feel as they get older that they more frequently experience occasions when they cannot immediately retrieve a word they know perfectly well ("it's on the tip of my tongue").
Tips of the tongue (TOTs) do indeed increase with age, and this increase is evident as early as the mid-thirties. There are other differences however, in the TOT experiences as people age. For example, older adults are much more likely to "go blank" than either young or mid-age (35-45) adults. That is, younger adults are more likely to be able to retrieve some information about the target word.
At all ages, the most common type of word involved in TOTs is proper names. But while forgetting proper names and object names becomes more common as we get older, interestingly, abstract words are forgotten less.
The most common means of resolution at all ages is that the forgotten word simply "pops up", but as we get older, it takes longer before this happens. "Pop-ups" are relatively more common for older adults. It is suggested that this may be because they are less likely to actively attempt to retrieve the information. According to a questionnaire, older adults are more likely to simply relax and think about something else.
Memory complaints linked to higher risk of MCI & dementia
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Data from 6257 older adults (aged 55-90) evaluated from 2005-2012 has revealed that concerns about memory should be taken seriously, with subjective complaints associated with a doubled risk of developing mild cognitive impairment or dementia, and subjective complaints supported by a loved one being associated with a fourfold risk. Complaints by a loved one alone were also associated with a doubled risk. Among those with MCI, subjective complaints supported by a loved one were associated with a threefold risk of converting to dementia.