Altered striatal functional gradients in obsessive-compulsive disorder

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Obsessive-compulsive disorder (OCD) involves functional changes in striatal brain connectivity.
• Previous characterizations of these striatal alterations in OCD are incomplete.
• Striatal gradients offer a novel method to map functional connectivity within the striatum.

Purpose of the Study:

• To map functional striatal gradients in individuals with OCD and healthy controls.
• To investigate the relationship between striatal gradient topology and OCD symptom severity over time.
• To identify how striatal connectivity differs during rest and during a threat-safety reversal task.

Main Methods:

• Spatial striatal gradients were computed from whole-brain activity in 52 individuals with OCD and 45 controls.
• Gradients were analyzed both at rest and during a threat-safety reversal task.
• A longitudinal dataset of 47 individuals with OCD was used to assess changes in gradient topology relative to symptom fluctuations.

Main Results:

• Significant group differences in resting-state striatal gradient topology were observed in the putamen and caudate regions.
• Individuals with decreasing OCD symptoms showed a shift in gradient topology towards that of controls.
• Differences in gradient topology related to safety-reversal (not threat-reversal) were found between groups in a region involving the nucleus accumbens and putamen.

Conclusions:

• Distinct changes in striatal topology are integral to OCD symptom expression.
• Findings highlight the role of striatal connectivity alterations in OCD.
• Future research should explore neural mechanisms of striatal topology dynamics and therapeutic strategies targeting striato-cortical plasticity.