A lot of us need to do a lot of sitting as part of our jobs, and it’s not uncommon for today’s people, in general, to sit down for long periods of time. But new research suggests that sitting might have a negative impact on memory, especially for those who are at least 40-years-old, or already in middle age.
According to the Los Angeles Times, a team of researchers from the Center for Cognitive Neurosciences at UCLA’s Semel Institute interviewed 35 people aged 45 to 75, all of whom were in good cognitive health. The subjects were asked questions about their levels of physical activity and underwent MRI tests to determine the thickness of their medial temporal lobe, a brain feature considered integral to learning and memory. Results of these tests were documented in the new study, which was published Thursday in the journal PLOS One.
The subjects reported different average sitting times, with some averaging as low as three hours a day, and others averaging as much as 15 hours. After the researchers made adjustments to take the participants’ ages into account, it was discovered that each additional hour spent sitting resulted in a 2 percent decrease in medial temporal lobe thickness. As the Los Angeles Times pointed out, this means that a person who sits 15 hours a day on average might have a medial temporal lobe that is 10 percent thinner than someone of the same age who sits down for an average of 10 hours a day. This finding was consistent regardless of the subjects’ broader levels of physical activity.
The potentially negative effect of sitting on a person’s memory adds to previous research that has associated sedentary behavior to a higher risk of conditions such as heart disease and diabetes, and a greater chance of premature death, according to Live Science. And while a 2 percent downtick in medial temporal lobe thickness might not sound like much, the researchers warned that the figures represent a significant loss in thickness. Furthermore, it’s such thinning of brain features that become more prominent in people who suffer from dementia, the Los Angeles Times added.
Although the researchers did not directly associate long hours of sitting with Alzheimer’s disease or other forms of dementia, they believe that reduction of sedentary behavior should be recommended as an intervention tool for people who are considered at risk of developing Alzheimer’s, according to Live Science.
With the study suggesting that sitting and poor memory might be linked to each other due to the effect of sedentary behavior on the medial temporal lobe, the researchers believe that their findings serve as a dire warning to couch potatoes, as regular exercise didn’t seem to “undo the damage” done by sitting. They added, however, that more extensive research is still needed, as only a few subjects were involved in the study. 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.