Neural signature of auditory hallucinations: comparison between schizophrenia patients with and without auditory hallucinations using 18F-FDG PET
Poster B51, Friday, October 21, 11:30 am - 1:00 pm, Le Baron
Nam-In Kang Kang1, Woo Sung Kim2, Young-Chul Chung2,3,4; 1Department of Psychiatry, Maeumsarang Hospital, Wanju, Jeollabuk-do, Korea, 2Department of Psychiatry, Chonbuk National University Medical School, Jeonju, Korea, 3Department of Psychiatry, Chonbuk National University Hospital, Jeonju, Korea, 4Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Korea
Aim: Auditory verbal hallucinations (AVH) is a common symptom that is reported by 50~80% of schizophrenia patients and sustains 25~30% of them despite appropriate pharmacological treatment. Understanding its exact pathophysiology is crucial in developing more optimal treatment strategies. We compared relative glucose metabolic rate (rGMR) between schizophrenia patients with and without auditory verbal hallucinations using [18F]-FDG PET. Methods: We recruited schizophrenia patients with (n=10) and without (n=12) prominent, predominant, and persistent AVH. AVH was evaluated using psychotic symptom rating scales-auditory hallucinations (PSYRATS-AH). Image acquisition began 40 minutes after [18F]-FDG injection, using a HRRT-PET scanner. Then, high-resolution structural data were acquired using a 7T MRI system. Results: The mean ages and duration of illness for patients with and without AVH were 39.20±10.55, 31.00±9.09 yrs, and 136.20±76.07, 112.50±78.01 ms, respectively. Compared to patients without AVH, significantly higher metabolic rates (thresholded at p ≤ 0.001, uncorrected, cluster size ≥ 20 voxels) in middle temporal gyrus, inferior temporal gyrus, fusiform gyrus, and putamen were observed in patients with AVH. Whole-brain correlation analysis with the PSYRATS total score in patients with AVHs yielded positive correlations in the middle temporal gyrus, inferior temporal gyrus, fusiform gyrus, putamen, posterior cingulate cortex, and thalamus and negative correlations in the superior frontal gyrus, middle frontal gyrus, and precuneus. Conclusions: Our results indicate that AVHs in patients with schizophrenia may be mediated by an alteration of neural pathways responsible for normal language function. Our findings also point to the potential role of the fusiform gyrus and putamen in the pathophysiology of AVHs. We discuss the relevance of findings in the study of AVHs.
Topic Area: Neuroimaging