Interoceptive dysfunction and its neural correlates in schizophrenia: protocol for a cross-sectional multimodal MRI study

Background Interoception—the perception and integration of internal bodily signals—is fundamental to emotion regulation, bodily self-awareness, and predictive coding. Emerging evidence suggests that interoceptive disturbances may contribute to core psychopathological features of schizophrenia. Our research group recently conducted a systematic review and meta-analysis demonstrating significant impairments in interoceptive accuracy and sensitivity among individuals with schizophrenia. However, the neural mechanisms underlying these deficits remain unclear. Methods This cross-sectional protocol will recruit 30 individuals with schizophrenia and 30 age- and sex-matched healthy controls. Participants will complete (1) behavioral interoceptive assessment using the heartbeat counting task; (2) subjective interoceptive questionnaires, including the Multidimensional Assessment of Interoceptive Awareness (MAIA) and the Body Perception Questionnaire (BPQ); (3) clinical symptom ratings (PANSS, HAM-A, HAM-D); and (4) cognitive testing (TMT, animal fluency, DSST). All participants will undergo multimodal MRI scanning, including structural T1-weighted imaging, resting-state fMRI, and diffusion tensor imaging. Neuroimaging data will be preprocessed and analyzed using DPABISurf, SPM12, and GRETNA. Expected Results: We anticipate that individuals with schizophrenia will show reduced interoceptive accuracy, altered subjective interoceptive awareness, and abnormal intrinsic neural activity and connectivity within interoception-related circuits, including the anterior insula, anterior cingulate cortex, amygdala, and thalamus. Structural abnormalities within thalamo-cortical pathways are also expected. Interoceptive deficits are hypothesized to correlate with symptom severity and cognitive performance. Conclusions This study will provide an integrated characterization of interoceptive dysfunction and its neural correlates in schizophrenia. Findings may advance understanding of bodily self-disturbance and emotional dysregulation and support the development of future interoception-focused therapeutic approaches. Clinical trial registration https://www.chictr.org.cn/ , identifier ChiCTR2500110551.