Functional brain abnormalities in panic disorder: A systematic review of functional magnetic resonance imaging studies.

Panic disorder (PD) is a psychiatric condition marked by recurring, unexpected panic attacks characterized by intense fear and rapid-onset physiological symptoms. Functional magnetic resonance imaging (fMRI) in individuals with PD has revealed abnormalities in several brain regions associated with fear processing, emotional regulation, and interoception. A systematic search was conducted in PubMed and Embase to review the fMRI changes associated with PD published until April 2024. Eighteen studies were included, primarily employing resting-state fMRI and examining functional connectivity. Consistent findings included amygdala and insula hyperactivity and reduced connectivity within the default mode network, particularly in the posterior cingulate cortex and precuneus. Altered connectivity patterns were also observed in the prefrontal cortex, anterior cingulate cortex, and hippocampus. Task-based fMRI studies revealed increased activity in fear-related regions that correlated with clinical measures of PD severity. This review consolidates the evidence of neural network disruptions in PD, emphasizing dysregulated fear processing, emotional regulation, and self-referential thinking. These findings highlight the potential of fMRI to elucidate the pathophysiology of PD and inform targeted interventions. However, the limited number of available studies, small sample sizes, and methodological heterogeneity, particularly among task-based fMRI studies, warrant cautious interpretation.