Exploring emotion regulation in PTSD with Insomnia: A task-based fMRI study.

Background: Sleep disturbances and difficulties in emotion regulation are core symptoms of post-traumatic stress disorder (PTSD) and are closely related. However, the neural mechanisms underlying this relationship remain underexplored. To address this gap, we used task-based functional magnetic resonance imaging (fMRI) to examine brain mechanisms related to emotional processing and regulation in PTSD patients with and without insomnia.

Methods: Forty-six PTSD patients (23 with insomnia, 23 without insomnia) and 28 controls reported clinical symptoms (including PTSD, insomnia, and anxiety/depression) and completed the Shifted Attention Emotion Appraisal Task (SEAT) during fMRI. We compared the neural differences in implicit emotion regulation-related regions between PTSD patients with and without insomnia based on both whole-brain and ROI analyses.

Results: Compared to PTSD patients without insomnia, those with comorbid insomnia exhibited significant deactivation in the left dorsolateral prefrontal cortex (BA46) and the left inferior frontal gyrus (triangular part, BA47) during implicit emotion processing. Additionally, during appraisal-based implicit emotion regulation, the left inferior temporal gyrus (BA37) showed significant deactivation. Furthermore, in the PTSD-insomnia group, insomnia severity was significantly correlated with activation in the left fusiform gyrus (BA37).

Conclusions: These findings highlight potential neural mechanisms underlying the differences between PTSD patients with and without insomnia. The observed alterations in these regions may serve as neural biomarkers for PTSD with comorbid insomnia and could be potential targets for developing novel therapeutic interventions.