Basal Ganglia & OCD

The basal ganglia is a region at the base of the brain that consists of three groups of neurons; the putamen, the globus pallidus and the caudate nucleus. It is responsible for involuntary movement behaviors like tremors. Some researchers are studying the theory that obsessive compulsive disorder (OCD) may be a result of abnormalities in the basal ganglia.

OCD

• Obsessive compulsive disorder is a condition in which an individual is locked into a pattern of repetitive behaviors such as hand washing, counting, repeating phrases and other, seemingly senseless activities.

Lesions

• A study published in "The Journal of Neuropsychiatry" linked obsessive compulsive disorder and behaviors to lesions in the basal ganglia region of the brain.

Acquired OCD

• Five women, age 61 to 77, were studied after developing late-onset acquired OCD. OCD typically surfaces when people are in their 20s or 30s. According to the study, "there are numerous reports of acquired OCD or OCBs [obsessive compulsive behaviors] that have a precipitous onset, occurring secondary to brain lesions."

Patients

• Of the five women studied, four had histories of depression but none had any history of OCD. Each woman had lesions on the basal ganglia that were discovered after symptoms of OCD surfaced.

Findings

• The study suggests, "basal ganglia lesions will further predispose depressed patients to the development of obsessive-compulsive behaviors." Though researchers stress that more research is needed.

Disruptions

• According to the study, there is a loop that runs from the front of the brain (the frontal cortex) to the basal ganglia and important information is sent through this loop. Lesions on the basal ganglia can disrupt the information. The study says, "The lesions found in the basal ganglia in our patients could account for their OCD behaviors if this pathway is dysregulated."