Surface-based brain morphometry in schizophrenia vs. cannabis-induced psychosis: A controlled comparison

Area of Science:

• Neuroimaging
• Psychiatry
• Brain Morphometry

Background:

• Investigating neurobiological differences between cannabis-induced psychosis (CIP), schizophrenia with heavy cannabis use (SZC), and healthy controls (HC).
• Understanding the impact of heavy cannabis use on brain structure in psychosis.

Purpose of the Study:

• To compare cortical thickness and surface parameters across three groups: SZC, CIP, and HC.
• To identify specific brain regions affected by these conditions.

Main Methods:

• Recruited 31 men with SZC, 28 with CIP, and 30 with HC.
• Utilized T1 MRI scans analyzed with Surface-based Brain Morphometry (SBM) via CAT-12 toolbox.
• Employed projection-based thickness and Desikan-Killiany atlas for cortical parcellation.

Main Results:

• Schizophrenia with heavy cannabis use (SZC) exhibited the lowest cortical thickness, depth, and gyrification, followed by CIP and HC groups.
• Significant reductions in cortical thickness were observed in SZC compared to HC, particularly in frontal regions.
• Negative correlations found between duration of cannabis use and cortical thickness in parietal and occipital regions.

Conclusions:

• Cortical structural abnormalities are evident in schizophrenia patients with heavy cannabis use, differing from cannabis-induced psychosis.
• Findings suggest distinct pathophysiological mechanisms underlying SZC and CIP.