AARP Eye Center
You’re going to want to get up from your chair after you read this. A new study by UCLA researchers indicates a link between sitting for long periods and reduced thickness of a brain region integral to the formation of new memories.
In the study, published in the journal PLOS ONE, the researchers recruited 35 people between the ages of 45 and 75 and asked about their level of physical activity and the average number of hours each day they spent sitting during the previous week. In addition, the subjects were given MRI scans so that the researchers could look at their medial temporal lobes.
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The researchers found the time spent sitting was a significant predictor of the amount of thinning in that brain area, which can be a forerunner of cognitive decline and dementia in middle-aged and older adults. The results suggest that a person who sits for 15 hours a day would have a medial temporal lobe that’s 10 percent thinner than someone the same age who sits for 10 hours.
Though previous studies have shown that physical activity positively affects thickness of some brain areas, the researchers didn’t find a link between their subjects’ exercise habits and medial temporal lobe thickness.
Prabha Siddarth, a biostatistician at the Semel Institute for Neuroscience and Human Behavior at UCLA and the study’s lead author, told the Los Angeles Times that even for people who exercise, extended sitting seems to be harmful to their brains.