Longitudinal changes in hippocampal volume in the Edinburgh High Risk Study of Schizophrenia

Area of Science:

• Neuroscience
• Psychiatry
• Genetics

Background:

• Schizophrenia is linked to brain abnormalities present before clinical onset.
• It's unclear if these are general vulnerability markers or related to the clinical state.
• The temporal progression of these brain alterations is also unknown.

Purpose of the Study:

• To investigate longitudinal changes in brain structure in individuals at high risk for schizophrenia.
• To determine if these changes represent general vulnerability or are associated with clinical development.
• To compare brain development trajectories between high-risk individuals and healthy controls.

Main Methods:

• Structural brain scans were acquired at two time-points in high-risk individuals and controls.
• Longitudinal sub-cortical reconstructions of the hippocampus and amygdala were generated.
• The high-risk cohort was analyzed based on clinical outcomes (remained well, developed symptoms, developed schizophrenia).

Main Results:

• Healthy controls showed a significant increase in hippocampal volume over time.
• High-risk individuals exhibited an altered hippocampal developmental trajectory compared to controls.
• No significant differences in longitudinal trajectories were found based on clinical outcome within the high-risk group.

Conclusions:

• Altered hippocampal volume developmental trajectory is associated with a general familial predisposition to schizophrenia.
• These findings suggest a trait-like marker of vulnerability rather than a state-dependent alteration.
• Early brain development changes may precede the onset of schizophrenia.