Subcortical neuromorphometry in schizophrenia spectrum and bipolar disorders

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Schizophrenia spectrum disorders and bipolar disorder share genetic links, but distinct biological phenotypes require further investigation.
• Advanced brain shape analysis methods enable detection of subtle surface deformations in psychiatric disorders.

Purpose of the Study:

• To identify common and distinct brain structure surface deformations across schizophrenia spectrum and bipolar disorder.
• To characterize differences in brain morphology related to these psychiatric conditions.

Main Methods:

• Utilized Large Deformation Diffeomorphic Metric Mapping (LDDMM) to analyze volumes and shapes of seven brain structures.
• Compared brain morphology in controls (n=40) and patients with schizophrenia (n=52), schizotypal personality disorder (n=12), psychotic bipolar disorder (n=49), and nonpsychotic bipolar disorder (n=24) aged 15-35.
• Investigated relationships between morphometric measures and clinical symptoms.

Main Results:

• Posterior thalamus showed inward deformation in schizophrenia (SCZ), psychotic bipolar disorder (P-BP), and nonpsychotic bipolar disorder (N-BP).
• Subiculum of the hippocampus exhibited inward deformation in SCZ and schizotypal personality disorder (STP).
• Volumetric differences were noted in the caudate, putamen, and globus pallidus after correcting for intracranial size. SCZ showed dispersed basal ganglia expansion patterns. Clinical symptom correlations were found with hippocampal, amygdalar, and thalamic volumes.

Conclusions:

• Limited shared surface deformation patterns suggest differing neuropathologies between SCZ and BP.
• Posterior thalamic contraction in SCZ and BP may indicate common genetic or environmental factors.
• Observed SCZ basal ganglia surface deformities might be influenced by antipsychotic medication effects.