A Shared Interoceptive-Swallow Gating Vulnerability in Panic Disorder

Panic disorder is commonly accompanied by choking sensations, respiratory alarm, fear of bodily catastrophe, and heightened monitoring of internal sensations. Separately, functional dysphagia and phagophobia can involve delayed or effortful swallow initiation despite little or no structural explanation. These phenomena are usually interpreted directionally: anxiety is presumed to produce secondary difficulty swallowing. We propose a different, testable possibility. In a clinically meaningful subgroup, panic symptoms and swallow-initiation dysfunction may be parallel expressions of a shared interoceptive-sensorimotor network vulnerability. The proposed network includes the insula, anterior cingulate cortex, dorsolateral prefrontal cortex, supplementary motor area, primary sensorimotor swallowing representations, and brainstem integrative nuclei involved in autonomic regulation and deglutition. Existing findings support each side of this bridge but have not directly tested the bridge itself. Panic disorder has been associated with altered insular and sensorimotor-network connectivity, while a small magnetoencephalography study of functional dysphagia found increased right-insular and prefrontal activation alongside reduced supplementary motor and sensorimotor activation during swallowing. We hypothesize that heightened interoceptive salience and self-monitoring can destabilize the transition from voluntary oral control to the patterned pharyngeal swallow, particularly under threat. We propose a preregistered, multicenter, four-group study of 240 adults: panic disorder with a swallow-initiation phenotype, panic disorder without that phenotype, swallow-initiation dysfunction without panic disorder, and healthy controls. The protocol combines structured psychiatric assessment, speech-language pathology evaluation, videofluoroscopic swallowing measures, autonomic and respiratory monitoring, repeated momentary state-anxiety measurement, structural MRI, resting-state connectivity, and task-based functional MRI during neutral and threat-anticipation swallowing conditions. The study is designed to distinguish a shared trait vulnerability from state anxiety, learned phobic avoidance, and occult organic dysphagia. Confirmation would support a mechanistically defined panic-swallow phenotype and motivate integrated interventions; disconfirmation would clarify that swallowing symptoms are better explained as downstream consequences or independent disorders.