Multi-scale predictions distinctively modulate tone perception in schizophrenia patients with auditory verbal hallucinations

Published: July 15, 2020, 8:01 a.m.

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.07.15.204495v1?rss=1 Authors: Yang, F., Zhu, H., Yu, L., Lu, W., Zhang, C., Tian, X. Abstract: Auditory verbal hallucinations (AVHs) are one of the most pronounced symptoms that manifest the underlying mechanisms of deficits in schizophrenia. Cognitive models postulate that malfunctioned source monitoring incorrectly weights the top-down prediction and bottom-up sensory processing and causes hallucinations. Here, we investigate the featural-temporal characteristics of source monitoring in AVHs. Schizophrenia patients with and without AVHs, and healthy controls identified target tones in noise at the end of tone sequences. Predictions of different timescales were manipulated by either an alternating pattern in the preceding tone sequences, or a repetition between the target tone and the tone immediately before. The sensitivity index, d prime, was obtained to assess the modulation of predictions on tone identification. We found that patients with AVHs showed higher d prime when the target tones conformed to the long-term regularity of alternating pattern in the preceding tone sequence than that when the targets were inconsistent with the pattern. Whereas, the short-term regularity of repetitions modulated the tone identification in patients without AVHs. Predictions did not influence tone identification in healthy controls. These findings suggest that malfunctioned source monitoring in AVHs heavily weights predictions to form incorrect perception. The weighting function in source monitoring can extend to the process of basic tonal features, and predictions at multiple timescales differentially modulate perception in different clinical populations. These collaboratively reveal the featural and temporal characteristics of weighting function in source monitoring of AVHs and suggest that the malfunctioned interaction between top-down and bottom-up processes might underlie the development of auditory hallucinations. Copy rights belong to original authors. Visit the link for more info