Not Motivated to Exercise? Blame Your Brain
If you can’t find the time or motivation to exercise, blame your brain.
Scientists from Seattle Children’s Research Institute have pinpointed the area of the brain that motivates people to exercise.
The study, conducted by Eric Turner and Yun-Wei Hsu, was conducted on mice. Researchers discovered that the dorsal medial habenula part of a mouse’s brain controls its desire to exercise. The dorsal medial habenula in rodents and humans is similar and functions in mood regulation and motivation.
This discovery not only could lead to ways of encouraging people to hit that treadmill, but it could also lead to better treatments for depression. Exercise is a known to be an effective, non-drug treatment for depression.
“Changes in physical activity and the inability to enjoy rewarding or pleasurable experiences are two hallmarks of major depression,” Turner says. “But the brain pathways responsible for exercise motivation have not been well understood. Now, we can seek ways to manipulate activity within this specific area of the brain without impacting the rest of the brain’s activity.”
Mice typically love to run on their exercise wheels. The study blocked signals from the dorsal medial habenula in genetically engineered mice, and found they were lethargic and ran far less. They also lost their preference for sweetened drinking water, a mouse treat.
In a second group of mice, Turner’s team activated the dorsal medial habenula using a precise laser technology. The mice could “choose” to activate this area of the brain by turning one of two response wheels with their paws. The mice strongly preferred turning the wheel that stimulated the dorsal medial habenula, demonstrating that this area of the brain is tied to rewarding behavior.
The study, “Role of the Dorsal Medial Habenula in the Regulation of Voluntary Activity, Motor Function, Hedonic State, and Primary Reinforcement,” was published recently by the Journal of Neuroscience and funded by the National Institute of Mental Health and National Institute on Drug Abuse.