FC25-02 - Functional MRI activation in response to panic-specific, non-panic aversive, and neutral imagery in patients with panic disorder and healthy controls

Abstract

Introduction

There is evidence that, besides limbic brain structures, prefrontal and insular cortical activations and deactivations are involved in the pathophysiology of panic disorder.

Objectives and aims

Using fMRI, this study investigated BOLD response patterns to stimulation with individually selected panic-specific pictures in patients with panic disorder with agoraphobia (PDA) and healthy controls. Structures of interest were the prefrontal, cingulate, and insular cortex, and the amygdalo-hippocampal complex.

Methods

21 PDA subjects (12 female, 9 male) and 21 matched controls were investigated using a Siemens 3 T scanner. Before, PDA subjects gave ratings on 120 pictures showing characteristic panic/agoraphobia situations (PA). 20 pictures with the individually highest ratings were selected. 20 matching pictures showing aversive but not panic-specific stimuli (A) and 80 neutral pictures (N) from the International Affective Picture-System (IAPS) were chosen for each subject. Anxiety and depression ratings were recorded.

Results

Group comparisons revealed a significantly greater BOLD response in PDA subjects than in controls in the insular cortices, left inferior frontal gyrus, dmPFC, the left hippocampal formation, and left caudatum (p < .005), when PA and N responses were compared. Group comparisons for stimulation with A compared to PA showed activation of similar brain regions in both groups but with different peak coordinates.

Conclusions

Results indicate specific activation patterns to panic-specific picture stimulation in PDA patients. Distinct peak coordinates between PA and A differ between groups. This might implicate that the brain circuits underlying processing of aversive stimuli might differ in their function in PDA patients compared to healthy subjects.