Some habits are helpful, such as automatically washing your hands before a meal or driving the same route to work every day. They accomplish an important task while freeing up valuable brain space.
But other habits — like eating a cookie every day after work — seem to stick around even when the outcomes aren’t so good.
Duke University neuroscientists have pinpointed a single type of neuron deep within the brain that serves as a “master controller” of habits.
The team found that habit formation boosts the activity of this influential cell, and that shutting it down with a drug is enough to break habits in sugar-seeking mice. Though rare, this cell exerts its control through a web of connections to more populous cells that are known to drive habitual behavior.
“This cell is a relatively rare cell but one that is very heavily connected to the main neurons that relay the outgoing message for this brain region,” said Nicole Calakos, an associate professor of neurology and neurobiology at the Duke University Medical Center. “We find that this cell is a master controller of habitual behavior, and it appears to do this by re-orchestrating the message sent by the outgoing neurons.”
The findings, published Sept. 5 in eLife, may point towards new treatments for addiction or compulsive behavior in humans.
The team got their first glimpse into the neurological underpinnings of habit in a 2016 study that explored how habits can leave enduring marks on the brain. The research was a collaborative effort between Calakos’ lab and Henry Yin, an associate professor in Duke’s department of psychology and neuroscience.