USA researchers have published preliminary studies that show that sitting down for too long can reduce the thickness of the medial temporal lobe, a brain structure that is very involved in memory.
Brain thinning is commonly known to cause risk of conditions that affect many older adults, like dementia and cognitive decline. For majority of people in office jobs, long sitting hours has become a norm.
So researchers at UCLA wanted to see how sedentary behavior influences brain health, especially regions of the brain that are critical to memory formation. UCLA biostatistician and study lead author Prabha Siddarth was also quoted by the Los Angeles Times as saying that "better ways to measure patterns of sedentary behavior" might be needed in upcoming studies.
A new study found that people who suffer brain injuries are at increased risk of dementia later in life. In one study, people who sat in front of a TV for more than four hours a day had nearly a 50 percent increased risk of death. The participants were asked to answer about their physical activity levels and the average number of hours each day they have spent sitting throughout the previous week.
In addition, thefindings are preliminary, and although the studyfocused on hours spent sitting, it did not take into consideration whether participants took breaks during long stretches of sedentary behavior. Using a high-resolution MRI scan, the scientists got a detailed look at the medial temporal lobe of each participant and identified relationships among this region's thickness, the participants' physical activity levels and their sitting behavior, according to the study. It was found that even high levels of physical activity could not offset the impact of sedentary practices, including lesser gray matter in the lobe.
In the future, researchers are aiming to find out whether sitting actually causes brain thinning and what role gender, race and weight might play in brain health in relation to sitting.
The study was supported by grants from various funders including the National Institutes of Health, the U.S. Department of Energy and the McLoughlin Gift Fund for Cognitive Health.