Precentral Gyrus Connectivity in Auditory Verbal Hallucinations: A Resting-State Functional MRI Study

The objective of this study was to analyze the functional connectivity (FC) of the precentral gyrus (PCG) bilaterally in a sample of patients with schizophrenia experiencing chronic auditory verbal hallucinations (AVH) including a control cohort of healthy volunteers.

A total of 105 subjects underwent resting-state functional magnetic resonance imaging (MRI) scanning, including 63 healthy control individuals (HC) and 42 schizophrenia patients experiencing AVH. A comparative approach was used to analyze the FC of the PCG bilaterally.

The present study detected increased resting-state FC (rsFC) involving the right PCG and three clusters distributed bilaterally across the frontal cortex, the supplementary motor area (SMA), paracingulate gyrus and the anterior cingulate gyrus (ACC), as well as hypoconnectivity between the right PCG and the lingual gyrus - bilaterally and the left occipital fusiform gyrus in schizophrenia as compared to HC. Furthermore, we observed hyperconnectivity between the left PCG and four clusters, including right paracingulate gyrus, ACC, right frontal pole (FP), precuneus, right pre- and postcentral gyri, right superior frontal gyrus (SFG), and right SMA. In addition, the patient group demonstrated hypoconnectivity between the left PCG and the right occipital pole, right lingual gyrus, right lateral occipital cortex, as well as the right cerebellar crus 1.

In the present study we observed a lateralized impairment in rsFC between the explored seeds and specific cortical and subcortical regions in schizophrenia. These alterations might contribute to the neurobiological pathways involved in schizophrenia pathogenesis with a focus on higher hallucination proneness.