# Working memory load-dependent modulation of neural activity predicts response to cognitive behavioral therapy in obsessive-compulsive disorder

## TL;DR

This study shows that brain activity during a memory task can predict how well people with obsessive-compulsive disorder will respond to cognitive behavioral therapy.

## Contribution

The study introduces a neurobiological marker based on working memory performance as a novel predictor of CBT response in OCD.

## Key findings

- Neural activity in the parietal lobule during a working memory task predicted CBT response in OCD patients.
- Higher modulation of brain activity was linked to greater symptom reduction after therapy.
- This marker outperformed clinical and demographic variables in predicting treatment outcomes.

## Abstract

Cognitive behavioral therapy (CBT) is an effective treatment for obsessive-compulsive disorder (OCD). However, CBT does not lead to a satisfying symptom reduction in a considerable number of patients with OCD. The identification of variables that predict insufficient treatment response could improve efficient treatment selection and inform the development of specific augmentative treatments. In the current study, we tested whether prediction of treatment response can be improved by including neurobiological markers during working memory (WM) performance. Forty-four patients with a primary OCD diagnosis participated in an n-back WM task with varying WM load while functional Magnetic Resonance Imaging (fMRI) was performed. Subsequently, all patients received CBT in an outpatient clinic. WM load-dependent modulation of the blood-oxygen-level-dependent (BOLD) signal in a bilateral cluster in inferior/superior parietal lobule predicted CBT response over and above clinical and sociodemographic variables (p < 0.05). Higher modulation was associated with larger relative symptom reduction. The results of the current study indicate that the ability of the WM system to flexibly adapt to changing task demands might be a useful indicator of CBT response in OCD. Possibly, this mechanism facilitates relearning processes during exposure-based CBT. However, findings need to be replicated in larger samples.