Serotonin2A receptor binding potential in people with aggressive and violent behaviour

Objective: Indexes of brain serotonin 2A (5-HT 2A ) density have never been investigated in a sample of humans with violent aggressive behaviour unbiased by medication use or current axis I psychiatric disorders. The objective of this study was to investigate prefrontal cortex 5-HT 2A binding potential (BP ND ), an index of 5-HT 2A density, in an unbiased sample of people with violent aggressive behaviour. Methods: We used [ 18 F] setoperone positron emission tomography to measure 5-HT 2A BP ND in the dorsolateral prefrontal cortex (primarily sampling Brodmann area 9) in 16 participants with violent aggressive behaviour and 16 healthy control participants. Results: In people with violent aggressive behaviours, the slope of 5-HT 2A BP ND decline in the dorsolateral prefrontal cortex is 44% less than in healthy control participants (analysis of variance group by age interaction, p = 0.004). Prefrontal cortex 5-HT 2A BP ND was significantly lower in participants with more severe impulsivity and aggression (multiple linear regression with age and Barratt Impulsivity Scale [BIS] as predictor variables and regional 5-HT 2A BP ND as dependent variable; effect of BIS, dorsolateral prefrontal cortex: F 1,13 = 7.95, p = 0.014). Conclusion: Lower prefrontal 5-HT 2A BP ND is related to violent aggression. Lower 5-HT 2A BP ND occurs at a younger age, when violent behaviour is more frequent, and is more prominent when impulsivity and aggression are more severe.