科学美国人60秒:When Old Habits Die Easy

Some say it’s tough to break a habit—a behavior so ingrained in our mental infrastructure that it’s automatic. But new research says maybe it’s not so tough when you shine some light on an alternative. 

Turns out that a small part of the brain’s prefrontal cortex—the infralimbic cortex—is key to seemingly inflexible, habitual behavior.

Scientists trained rats to run a maze by using rewards. Eventually the rats ran the maze without any reward, or even when being punished by completing it with a  drink that made them nauseous. So running the maze in a certain direction had become a habit. 

The scientists then used what’s called optogenetics—a procedure that uses light to stimulate or inhibit specific brain areas—to turn “off” this small brain area involved in forming habits.

Within seconds the rats stopped running the maze in the direction that gave them the icky reward. The scientists note that silencing the neurons in that brain area allowed the rats to have more cognitive control over their supposedly reflexive habit of running in that one direction.

The hope is to eventually treat disorders involving obsessive or addictive behavior. And to hopefully show that old habits can die easy.

—Christie Nicholson