Abnormal Effective Connectivity in the Brain is Involved in Auditory Verbal Hallucinations in Schizophrenia
Information flow among auditory and language processing-related regions implicated in the pathophysiology of auditory verbal hallucinations (AVHs) in schizophrenia (SZ) remains unclear. In this study, we used stochastic dynamic causal modeling (sDCM) to quantify connections among the left dorsolateral prefrontal cortex (inner speech monitoring), auditory cortex (auditory processing), hippocampus (memory retrieval), thalamus (information filtering), and Broca’s area (language production) in 17 first-episode drug-naïve SZ patients with AVHs, 15 without AVHs, and 19 healthy controls using resting-state functional magnetic resonance imaging. Finally, we performed receiver operating characteristic (ROC) analysis and correlation analysis between image measures and symptoms. sDCM revealed an increased sensitivity of auditory cortex to its thalamic afferents and a decrease in hippocampal sensitivity to auditory inputs in SZ patients with AVHs. The area under the ROC curve showed the diagnostic value of these two connections to distinguish SZ patients with AVHs from those without AVHs. Furthermore, we found a positive correlation between the strength of the connectivity from Broca’s area to the auditory cortex and the severity of AVHs. These findings demonstrate, for the first time, augmented AVH-specific excitatory afferents from the thalamus to the auditory cortex in SZ patients, resulting in auditory perception without external auditory stimuli. Our results provide insights into the neural mechanisms underlying AVHs in SZ. This thalamic-auditory cortical-hippocampal dysconnectivity may also serve as a diagnostic biomarker of AVHs in SZ and a therapeutic target based on direct in vivo evidence.
KeywordsEffective connectivity Stochastic dynamic causal modeling Auditory verbal hallucinations Schizophrenia
This study was supported by the National Key Basic Research and Development Program (973) (2011CB707805), the National Natural Science Foundation of China (81571651, 81301199, and 81230035), and the Fund for the Dissertation Submitted to Fourth Military Medical University for the Academic Degree of Doctor, China (2014D07). We thank Dr. Lijun Bai, Xi’an Jiaotong University, for her help on revising the manuscript.
- 15.Mondino M, Jardri R, Suaud-Chagny MF, Saoud M, Poulet E, Brunelin J. Effects of fronto-temporal transcranial direct current stimulation on auditory verbal hallucinations and resting-state functional connectivity of the left temporo-parietal junction in patients with schizophrenia. Schizophr Bull 2016, 42: 318–326.CrossRefPubMedGoogle Scholar
- 18.Seok JH, Park HJ, Chun JW, Lee SK, Cho HS, Kwon JS, et al. White matter abnormalities associated with auditory hallucinations in schizophrenia: a combined study of voxel-based analyses of diffusion tensor imaging and structural magnetic resonance imaging. Psychiatry Res 2007, 156: 93–104.CrossRefPubMedGoogle Scholar
- 50.Friston KJ, Stephan K, Li BJ, Daunizeau J. Generalised Filtering. Math Probl Eng 2010, 2010: Article ID 621670.Google Scholar