Although cognitive behavioral therapy (CBT) is an effective treatment for pediatric OCD, not all patients respond to it equally — with some seeing little to no decrease in symptoms.

This study by Dr. Nurmi and her team aimed to examine whether glutamate (one of the most important neurotransmitters linked to learning, memory, and mood), which has been extensively studied over the years due to its connection with OCD and treatments, could serve as a biomarker for how effective a course of CBT is on patients with pediatric OCD. 49 children with OCD and 29 controls had two areas of the cingulate cortex — the pregenual anterior cingulate cortex (pACC; associated with emotion, conflict, and social cognition) and the ventral posterior cingulate cortex (vPCC; associated with sensory input) — scanned during different times using magnetic resonance spectroscopy (a form of neuroimaging). Some participants in the OCD group received a 12-14 week course of CBT immediately, while others were put on an eight-week waitlist after which they received CBT as well. At baseline, glutamate levels did not differ in the OCD and control group; however, after receiving CBT, glutamate levels in the pACC  decreased significantly. Higher glutamate levels in the vPCC at baseline were predictors of poor response to CBT. This study gave further support to theories behind glutamate’s role in OCD.

Resulting Publication:

*O’Neill, J., Piacentini, J., Chang, S., Ly, R., Lai, T.M., Armstrong, C.C., Bergman, L., Rozenman, M., Peris, T., Vreeland, A., Mudgway, R., Levitt, J.G., Salamon, N., Posse, S., Hellemann, G.S., Alger, J.R., McCracken, J.T., & Nurmi, E.L. (2017). Glutamate in pediatric obsessive-compulsive disorder and response to cognitive-behavioral therapy: Randomized clinical trial. Neuropsychopharmacology, 42, 2414-2422. doi:10.1038/npp.2017.77