Volumes of Orbito-Frontal Cortex and Thalamus in Patients with Obsessive-Compulsive Disorder Before and After the Cognitive Behavioral Therapy

Bilişsel Davranışçı Terapi Öncesi ve Sonrası Obsesif Kompulsif Bozukluğu Olan Hastalarda Orbito-Frontal Korteks Ve Talamus Hacimleri

There are no sufficient numbers of studies that investigate the effects of various treatment methods, psychopharmacological and cognitive behavioral therapy (CBT) included, on brain volumes and neurochemicals in patients with Obsessive-Compulsive Disorder (OCD). A study focused on the effects of the CBT over the volumes of the orbito-frontal cortex and thalamus regions that seemed to be abnormal in OCD patients.

The same numbers of OCD patients and healthy individuals were included in the study. The pre-CBT orbito-frontal cortex (OFC) and thalamus volumes of the patients and healthy individuals were compared by using the magnetic resonance imaging (MRI). Subsequently, the volumes of these regions were measured following the CBT treatment. Furthermore, the patients were subjected to the Y-BOCS (Yale-Brown obsession compulsion scale) before and after the CBT.

The volumes of the orbito-frontal cortex (OFC), thalamus, caudate nucleus and anterior cingulate were evaluated: It was determined that OCD patients had a significantly smaller volume of right-left OFC and a bigger volume of right-left thalamus, compared to healthy individuals. When the pre-CBT and post-CBT data of the patients were compared, it was found that the thalamus volume reduced substantially for both parties and that the orbito-frontal cortex volumes significantly increased only for the left part during the procedure. Moreover, a statistically-significant decrease was found in the post-CBT Y-BOCS scores of the OCD patients. This finding supports the idea that a regular CBT treatment has a significant effectiveness in reducing the obsessive-compulsive symptoms in OCD patients.

In brief, it was observed that the CBT could affect significant brain regions that take part in the neuroanatomy of OCD.

Atmaca, M., Yildirim, H., Yilmaz, S., Caglar, N., Mermi, O., Korkmaz, S., … Turkcapar, H. (2016). Orbito-frontal cortex and thalamus volumes in the patients with obsessive-compulsive disorder before and after cognitive behavioral therapy. The International Journal of Psychiatry in Medicine, 53(4), 243–255.

Prof. Dr. Kemal Arıkan