The conclusion belongs to a new study

Sep 15, 2009 14:43 GMT  ·  By

Many experts believe that the average human brain starts shrinking with old age, and that the trend continues until death. But a new study comes to disagree with them, stating that, in healthy individuals, no such regression can be found, regardless of age. The same paper hints at the fact that the diminishing of the brain starts only when the cognitive abilities of that specific person begin to deteriorate, LiveScience reports. Details of the new investigation are published in the September issue of the respected scientific journal Neuropsychology.

“The main issue is that maybe healthy people do not have as much atrophy as we always thought they had,” Maastricht University PhD candidate Saartje Burgmans, also the lead author of the new study, explains. The scientist believes that one of the main reasons why previous studies overestimated the amount by which the old brain started shrinking was because the researchers who conducted them failed to exclude people who were already beginning to develop conditions such as dementia, or other related illnesses. If they had been separated from the healthy participants, the conclusions of the new research would have been reached a long time ago.

“What we found is that when you exclude all those people [who] are suspicious for preclinical disease, and you just look at the healthy people who don't have any suspicious cognitive decline, then you see that there is a very small age effect in this group,” Burgmans says. In the study, participants were divided into two groups. The first, made up of healthy individuals, had 35 members, while the second, made up of people who had already begun to develop symptoms associated with dementia and related conditions, numbered 30 members.

By using brain Magnetic Resonance Imaging, the science team observed the effects of old age on seven brain regions that had been associated with cognition in previous investigations. In the healthy group, they noticed no statistically significant differences. In the other group, they noticed signs of decline in all seven areas. The investigation again revealed the importance of experts studying the aging brain taking into account the cognitive health of their test subjects over a number of years.