RT Journal Article SR Electronic T1 Paracingulate sulcus morphology and hallucinations in clinical and non-clinical groups JF bioRxiv FD Cold Spring Harbor Laboratory SP 284752 DO 10.1101/284752 A1 Jane R. Garrison A1 Charles Fernyhough A1 Simon McCarthy-Jones A1 Jon S. Simons A1 Iris E.C. Sommer YR 2018 UL http://biorxiv.org/content/early/2018/03/19/284752.abstract AB Hallucinations are a characteristic symptom of psychotic mental health conditions that are also experienced by many individuals without a clinical diagnosis. Research has linked the experience of hallucinations in schizophrenia to differences in the length of the paracingulate sulcus (PCS), a structure in the medial prefrontal cortex of the brain which has previously been associated with the ability to differentiate perceived and imagined information. We investigated whether this notion of a specific morphological basis for hallucinations in the paracingulate cortex extends to individuals without a clinical diagnosis by testing the hypothesis that non-clinical individuals with hallucinations have shorter PCS than non-clinical individuals without hallucinations. Structural MRI scans were examined from three demographically matched groups of individuals: 50 patients with psychotic diagnoses who experienced auditory verbal hallucinations, 50 non-clinical individuals with auditory verbal hallucinations, and 50 healthy control subjects with no life-time history of hallucinations. Measurements of paracingulate sulcal length were compared between the groups and the results verified using automated data-driven gyrification analyses. Patients with hallucinations had shorter PCS than both healthy controls and non-clinical individuals with hallucinations, with no difference between non-clinical individuals with hallucinations and healthy controls. These findings suggest that the association of shorter PCS length with hallucinations is specific to patients with a psychotic disorder. This presents challenges for continuum models of psychosis and suggests possible differences in the mechanisms underlying hallucinations in clinical and non-clinical groups.