Brain Decline Begins At Age 27

krou writes "The BBC is reporting that a new study suggests that our mental abilities start to dwindle at 27 after peaking at 22, and 27 could be seen as the 'start of old age.' The seven-year study, by Professor Timothy Salthouse of the University of Virginia, looked at 2,000 healthy people aged 18-60, and used a number of mental agility tests already used to spot signs of dementia. 'The first age at which there was any marked decline was at 27 in tests of brain speed, reasoning and visual puzzle-solving ability. Things like memory stayed intact until the age of 37, on average, while abilities based on accumulated knowledge, such as performance on tests of vocabulary or general information, increased until the age of 60.'"

Comments

Re:Noooooo!

[Sponge Bath]

The time is gone, the song is over,
Thought I'd something more to say.

39?

[chromis]

I always thought that the brain works best at 39 ;) http://science.slashdot.org/article.pl?sid=08/10/27/1630225

Re:Confounding Variable

[yali]

Googling the name of the journal, Neurobiology of Aging, leads to the abstract for this study:

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. However, the validity of cross-sectional comparisons of cognitive functioning in young and middle-aged adults has been questioned because of the discrepant age trends found in longitudinal and cross-sectional analyses. 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. 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.

In other words, the researchers were wayyyy ahead of slashdot. They analyzed both cross-sectional and prospective longitudinal designs. They modeled and controlled for potential confounds due to (a) sampling bias in cross-sectional comparisons (point raised by grandparent) and (b) practice-effect biases in longitudinal comparisons (because if you take any test twice, you'll probably do better the second time). They also validated their results with other methods (like neurobiological assessments). What they got was a convergence of results from multiple methods, which is exactly what good science is supposed to be.