Slashdot Mirror
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.'"
... or perhaps the reason they saw declining figures starting at the age of 27, is that older people who are more intelligent, tend to not have the time, choose not to waste the effort, and do not need the $100, to participate in these kinds of studies.
That's the problem with doing these kinds of studies as a point-measurement across an age-range. The test groups cannot possibly be equivalent, unless a VERY large sample is taken at random from the population. Frankly, I'll have trouble believing such a study unless it's a prospective study that tests the same volunteers across a span of their lifetime.