Auditory verbal hallucinations in first episode psychosis – an fMRI symptom capture study

Abstract

Introduction

Neurobiological models of auditory verbal hallucination (AVH) have been advanced by symptom capture functional magnetic resonance imaging (fMRI), where participants self-report hallucinations during scanning. To date, regions implicated are those involved with language, memory and emotion. However, previous studies focus on chronic schizophrenia, thus are limited by factors, such as medication use and illness duration. Studies also lack detailed phenomenological descriptions of AVHs. This study investigated the neural correlates of AVHs in patients with first episode psychosis (FEP) using symptom capture fMRI with a rich description of AVHs. We hypothesised that intrusive AVHs would be associated with dysfunctional salience network activity.

Methods

Sixteen FEP patients with frequent AVH completed four psychometrically validated tools to provide an objective measure of the nature of their AVHs. They then underwent fMRI symptom capture, utilising general linear models analysis to compare activity during AVH to the resting brain.

Results

Symptom capture of AVH was achieved in nine patients who reported intrusive, malevolent and uncontrollable AVHs. Significant activity in the right insula and superior temporal gyrus (cluster size 141 mm³), and the left parahippocampal and lingual gyri (cluster size 121 mm³), P < 0.05 FDR corrected, were recorded during the experience of AVHs.

Conclusions

These results suggest salience network dysfunction (in the right insula) together with memory and language processing area activation in intrusive, malevolent AVHs in FEP. This finding concurs with others from chronic schizophrenia, suggesting these processes are intrinsic to psychosis itself and not related to length of illness or prolonged exposure to antipsychotic medication.

Disclosure of interest

The authors have not supplied their declaration of competing interest.