Intraparietal sulcus depth is associated with negative symptomatology in patients with first-episode psychosis

The study of brain morphology parameters in patients with first-episode psychosis (FEP) could help detect early brain footprints related to this disease and its predominant symptomatology. We examined gray matter (GM) volume, cortical thickness (CT), gyrification index (GI), and sulcus depth (SD) differences between patients with FEP and healthy control (HC) participants. We also investigated the associations of these brain parameters with symptomatology in FEP. Our sample consisted of 182 participants, 105 patients with FEP and 77 HC. All participants had a brain structural image acquired with a 3T scanner. Symptomatology was assessed with the Positive and Negative Syndrome Scale (PANSS), considering both the original 3-factor structure and an alternative 5-factor structure proposed by Emsley. Patients with FEP showed reduced GM volume than HC in the anterior cingulate gyrus and adjacent regions. We also found that greater SD of the intraparietal sulcus was associated with more severe negative symptomatology in FEP. This association was found with the total score of this subscale and several of its items. Additionally, lower SD and lower CT in the right parietal lobe were associated with a higher Emsley's excited factor score, which includes items related to manic symptoms. Our results suggest that an abnormal depth of the intraparietal sulcus may be an indicator of impaired functioning of this region, which may in turn be associated with social and emotional issues. Overall, SD seems to provide relevant information on the brain morphology of FEP, making it a promising marker for the early stages of psychosis.