Why are habits so hard to break?
By Contributor
Taming that sweet tooth for your New Year's resolution may be harder than you think. New research suggests that habits change the brain …
Why habits are hard to break?
By now, you might have discovered that taming your sweet tooth as a New Year's resolution is harder than you think.
New research by Duke University scientists suggests that a habit leaves a lasting mark on specific circuits in the brain, priming us to feed our cravings.
How a habit changes the brain
The researchers compared the brains of mice that had formed a habit to the ones that didn't. In particular, the team studied electrical activity in the basal ganglia, a complex network of brain areas that controls motor actions and compulsive behaviors, including drug addiction.
In the basal ganglia, two main types of paths carry opposing messages: One carries a 'go' signal which spurs an action, the other a 'stop' signal.
Experiments by Duke Neurobiology graduate student Justin O'Hare found that the stop and go pathways were both more active in the sugar-habit mice. O'Hare said he didn't expect to see the stop signal equally ramped up in the habit brains, because it has been traditionally viewed as the factor that helps prevent a behavior.
The team also discovered a change in the timing of activation in the two pathways. In mice that had formed a habit, the go pathway turned on before the stop pathway. In non-habit brains, the stop signal preceded the go.
These changes in the brain circuitry were so long-lasting and obvious that it was possible for the group to predict which mice had formed a habit just by looking at isolated pieces of their brains in a petri dish.
Breaking a habit
To see if they could break a habit, the researchers encouraged the mice to change their habit by rewarding them only if they stopped pressing the lever.
The mice that were the most successful at quitting had weaker go cells. But how this might translate into help for humans with bad habits is still unclear.
Calakos said some researchers are beginning to explore the possibility of treating drug addiction using Tran’s cranial magnetic stimulation or TMS, a non-invasive technique that uses magnetic pulses to stimulate the brain.
