Cortico-Autonomic Dysregulation in Generalized Anxiety Disorder and Irritable Bowel Syndrome: A Combined EEG–HRV Case Study

This case study presents an in-depth exploration of two women with comorbid generalized anxiety disorder (GAD) and severe irritable bowel syndrome (IBS), highlighting the intersection of psychophysiological stress and autonomic regulation through quantitative electroencephalography (qEEG) and heart rate variability (HRV). The patients, aged 60 and 50 years, both exhibited significant somatic symptoms (e.g., chronic constipation, abdominal pain, and emotional distress) closely intertwined with complex psychosocial and psychosexual dynamics. The therapeutic process aimed at addressing autonomic imbalances and stress regulation revealed striking patterns of neurophysiological hyperarousal in both cases. At baseline, qEEG findings revealed excess beta activity, primarily in the 25-30 Hz range, indicating a state of cortical hypervigilance. Both patients also exhibited low parasympathetic activity (as indicated by RMSSD and HF power) and elevated sympathetic dominance (shown by LF/HF ratios and SNS index), confirming the presence of cortico-autonomic dysregulation. While both patients made progress in symptom management, therapy was prematurely discontinued after 13-14 sessions due to persistent cognitive-emotional rigidity and psychosocial barriers. These findings underline the role of interoceptive awareness, emotional regulation, and autonomic flexibility in therapeutic engagement and recovery. The clinical implications are twofold: (1) the EEG–HRV profile provides a stable, objective measure of cortico-autonomic hyperarousal that can serve as a biomarker of therapeutic progress and engagement; and (2) psychosocial dynamics, including rigid behavioral patterns and longstanding emotional conflicts, must be concurrently addressed for effective treatment. The study suggests the need for longitudinal research to examine how autonomic regulation and cortical rhythms evolve with multimodal interventions, such as HRV biofeedback.