Sep 09 2009
Another Myth on Aging Busted
At one time it was standard developmental psychology material to profess that seniors lose up to 10% of their brain mass. I recall teaching it myself. I was wrong. Yikes. Seems you can’t even trust textbooks!
Scratch that. You shouldn’t have full confidence in everything in a textbook. Particularly those in the “softer” sciences.
One thing is for certain — science is exciting.
So how was this error made?
The belief that healthy older brains are substantially smaller than younger brains may stem from studies that did not screen out people whose undetected, slowly developing brain disease was killing off cells in key areas, according to new research. As a result, previous findings may have overestimated atrophy and underestimated normal size for the older brain.
Rather than normal aging causing a startlingly large change in brain mass, it seems that the pathological changes in the brains of a proportion of the elderly threw off the results. Minus those with some form of dementia (cognitive loss), the average loss is much smaller. So no, age itself won’t cause your braincase to become, in effect, one size too large.
[source]
