People with compulsive behavior disorders such as OCD, binge eating, and substance abuse share a pattern of decision making, according to University of Cambridge researchers.
They found that individuals with compulsive behaviors have fewer nerve cells (less gray matter) in their orbitofrontal cortex and striatum, parts of the brain that keep track of rewards and goals. This affects the way people make decisions.
Two Types of Decisions
Human beings make choices either out of habit or to achieve a specific end. Habitual choices are what we often refer to as “being on autopilot.” An example is driving to and from work—most of us drive the same daily route made of habitual choices.
If we get a new job in a different part of town, then for a while we will drive to and from work using goal-directed route decisions. Once or twice we might slip into autopilot and drive to our old place of employment by mistake. Eventually, we will get into a habit of going to and from the new place a certain way, and our route will again become habitual.
Because we do not always control our decision process, we might make habitual choices even knowing they are not in our best interest. For instance, we might grab a donut for breakfast and wolf it down though we are trying to lose five pounds. Taken to extremes, this decision behavior can develop into compulsive disorders.
Different Disorders with Common Thread
The Cambridge investigators studied people of similar age and gender with OCD, methamphetamine dependence, obesity with binge eating, and healthy individuals. They found all the disorders were associated with a shift to habitual autopilot choices instead of using goal-directed ones.
The tendency to use habitual decisions is linked to having less gray matter, or fewer nerve cells, in the orbitofrontal cortex and striatum. Even healthy participants who had fewer nerve cells in their brain’s decision and reward areas tended to make more habitual choices.
“Seemingly diverse choices - drug taking, eating quickly despite weight gain, and compulsive cleaning or checking - have an underlying common thread: rather than a person making a choice based on what they think will happen, their choice is automatic or habitual,” said researcher Dr. Valerie Voon. “
Now that researchers understand the glitch in decision making that leads to compulsive behavior, they hope future therapy treatment will emphasize goal-directed planning, and that medications will be developed to offset the habitual choice tendency.
Source: Science Daily
Photo credit: William Ward
