Antipsychotics cause reversible structural brain changes within one week.

Area of Science:

• Neuroimaging
• Pharmacology
• Psychiatry

Background:

• Understanding antipsychotic effects on brain structure is vital for interpreting neuroimaging studies in patients.
• Distinguishing drug effects from illness progression in brain MRI is a significant challenge.

Purpose of the Study:

• To investigate whether antipsychotic exposure alters brain MRI structural metrics in healthy volunteers, independent of disease effects.
• To assess the transient nature of these potential drug-induced changes.

Main Methods:

• A randomized, double-blind, crossover, placebo-controlled study in healthy participants.
• One-week administration of amisulpride (400 mg/day) or aripiprazole (10 mg/day), followed by placebo, or vice versa.
• Analysis of brain MRI structural metrics including volumetric estimates, cortical thickness, surface area, and T1-relaxation time.

Main Results:

• Amisulpride increased left putamen and right caudate volumes compared to placebo.
• Aripiprazole increased right putamen volume compared to placebo.
• No significant changes were observed in cortical metrics or T1-relaxation time; striatal changes reversed rapidly upon drug withdrawal.

Conclusions:

• Short-term antipsychotic exposure causes transient, reversible increases in striatal volume.
• These findings suggest that some striatal volumetric differences in schizophrenia patients may be due to antipsychotic medication effects.