(From Science Daily) A group of “professional couch potatoes,” as one researcher described them, has proven that even moderate exercise — in this case walking at one’s own pace for 40 minutes three times a week — can enhance the connectivity of important brain circuits, combat declines in brain function associated with aging and increase performance on cognitive tasks.

The study, in Frontiers in Aging Neuroscience, followed 65 adults, aged 59 to 80, who joined a walking group or stretching and toning group for a year. All of the participants were sedentary before the study, reporting less than two episodes of physical activity lasting 30 minutes or more in the previous six months. The researchers also measured brain activity in 32 younger (18- to 35-year-old) adults.

Rather than focusing on specific brain structures, the study looked at activity in brain regions that function together as networks.

“Almost nothing in the brain gets done by one area — it’s more of a circuit,” said University of Illinois psychology professor and Beckman Institute Director Art Kramer, who led the study with kinesiology and community health professor Edward McAuley and doctoral student Michelle Voss. “These networks can become more or less connected. In general, as we get older, they become less connected, so we were interested in the effects of fitness on connectivity of brain networks that show the most dysfunction with age.”

Neuroscientists have identified several distinct brain circuits. Perhaps the most intriguing is the default mode network (DMN), which dominates brain activity when a person is least engaged with the outside world — either passively observing something or simply daydreaming.

Previous studies found that a loss of coordination in the DMN is a common symptom of aging and in extreme cases can be a marker of disease, Voss said.

Read more here: Attention, Couch Potatoes! Walking Boosts Brain Function