|
|
Specifically, the research performed at the University of Virginia states that the mental abilities of humans peak at the age of 22 years and then begins to decrease at the age of 27 years.
American psychologist Timothy A. Salthouse, from the Department of Psychology at the University of Virginia in Charlottesville (United States), is the author of this study
Dr. Salthouse, the director of the Salthouse Cognitive Aging Laboratory at the University of Virginia, studied 2,000 male and female adults between the ages of 18 to 60 years over a seven-year period.
The health of these people was considered good and the their educational background was considered well above average.
During the seven years of study, the participants were asked to perform twelve tests that are often asked of dementia and Alzheimer’s disease patients.
Such tests involve solving visual puzzles, identifying patterns in symbols and letters, and remembering words and details of stories.
Salthouse found that in nine of the twelve tests, the average age of peak performance was at 22 years.
Page two continues with more results from Dr. Salthouse.
In addition, this Virginia researcher found that in three tests of reasoning, spatial visualization, and speed of thinking the age at which these people scored much lower than their peak scores was at the age of 27 years.
|
According to the paper When does age-related cognitive decline begin?, cognitive aging—that is, the decline in the ability of the brain to think and process information—begins in “healthy educated adults when they are in their 20s and 30s.”
The paper was published online on February 24, 2009, and is in the April issue (volume 30, issue 4, pages 507-514) of the journal Neurobiology of Aging.
The author states in the abstract of his paper, “Cross-sectional comparisons have consistently revealed that increased age is associated with lower levels of cognitive performance, even in the range from 18 to 60 years of age.”
Salthouse disputes the validity of cross-sectional comparisons when applied to cognitive functioning of the brain in young and middle-aged adults because of the wide variance of ages in when these studies say cognitive decline begins.
He states that, “The results of the current project suggest that a major factor contributing to the discrepancy is the masking of age-related declines in longitudinal comparisons by large positive effects associated with prior test experience.”
The author adds, “Results from three methods of estimating retest effects in this project, together with results from studies comparing non-human animals raised in constant environments and from studies examining neurobiological variables not susceptible to retest effects, converge on a conclusion that some aspects of age-related cognitive decline begin in healthy educated adults when they are in their 20s and 30s.”
Page three concludes with a critique of Dr. Salthouse's conclusions.
The paper by Dr. Salthouse is not without its critics.
|
The authors--Lars-Göran Nilssonadef, Ola Sternängad, Michael Rönnlundbg, and LarsNybergcdef--state in their abstract, “Salthouse claims that cognitive aging starts around 20 years of age. The basis for this claim is cross-sectional data. He dismisses longitudinal data, which typically show the cognitive decline to start much later, around 60 years of age.”
They add, "He states that longitudinal data cannot be trusted because they are flawed. There is a confounding between the effects of maturation and retest effects. We challenge Salthouse’s strong claim ….”
Additional information is needed to verify the claims by Salthouse.
To minimize the declines of mental aging, it might be prudent, in addition, to verifying these claims, to institute anti-aging programs earlier than is currently done.
Even though we think that aging starts in ones 60s, it might, indeed, start gradually over a lifetime and actually begin in your twenties or thirties. More research is needed, in any case.
