The brain’s failure in obsessive compulsive disorder

Obsessive-compulsive disorder (OCD) was previously considered an anxiety disorder but is now classified as a mental illness. About 2.3 percent of the population suffers with this common, chronic and long-lasting disorder.

In the United States, the current numbers approximate 3.3 million, although some estimates have been as high as 6 million, related, in part, to how patients are diagnosed and categorized. But a recent study in the U.K. that illustrates how the OCD brain reacts compared to the average brain may help better treat these patients.

One-third of affected adults first experience symptoms in childhood, and the median age of onset is 19, with 25 percent of cases occurring by age 14. However, fewer than half of those with OCD will seek effective treatment — often delaying treatment up to nine years in the hope that symptoms will alleviate or because they feel embarrassed, ashamed or have negative connotations about getting professional help.

For everyone, the ability to assign safety to stimuli in the environment is integral to everyday functioning. The troubling symptoms of OCD include uncontrollable, reoccurring thoughts (obsessions, such as fear of germs, unwanted thoughts involving sex, religion and harm, and having things symmetrical or in a perfect order) and behaviors (compulsions, such as excessive cleaning and/or hand washing, ordering and arranging things in a particular way, and repeatedly checking on things) that ultimately interfere with daily life.

A recent brain-scanning study has found that the part of the brain that sends out safety signals seems to be less active in people with OCD. Naomi Fineberg of Hertfordshire Partnership University NHS Foundation Trust in the U.K. and her team trained 78 people (about half had OCD) to fear a picture of an angry face to help explore the rituals of OCD.

A key brain region for this evaluation is the ventromedial prefrontal cortex (vmPFC). To investigate the importance of vmPFC safety signaling, the team used neuroimaging of Pavlovian fear reversal, a paradigm that involves flexible updating when the contingencies for a threatening (CS+) and safe (CS-) stimulus reverse, in a prototypical disorder of inflexible behavior influenced by anxiety, OCD.

Sometimes the volunteers were given an electric shock to the wrist when they saw the angry face picture while they were lying in a functional magnetic resonance imaging (fMRI) brain scanner. Then, the volunteers were shown the picture many times without a shock in a detraining effort.

Eventually, those without OCD stopped associating the face with a shock, but researchers noted that those with OCD remained afraid of the face even after the shocks had stopped. Importantly, those volunteers with OCD showed less activity in their vmPFC.

A common treatment for OCD includes exposure response prevention or focused therapy, that involves people trying to experience their triggers without resorting to their rituals basically helping them realize that nothing bad happens. However, most OCD patients who undergo this therapy fail to eliminate all of their repetitive behaviors. Many are not helped at all.

The results of this study may provide insight into the difficulty of why this approach probably takes longer than originally thought and why those with OCD need to stick with their therapy. Some researchers contend that drugs such as psilocybin, a compound in magic mushrooms that causes euphoria administered during therapy might help those with OCD to pay attention to the fact that nothing bad happens when they abandon their rituals.