Objective: To explore what brain regions are modulated by heroin addiction and withdrawal.
Methods: We used functional magnetic resonance imaging to investigate the brain function in 15 heroin-dependent patients 3 days (acute) and 1 month (protracted) after heroin abstinence. Sixteen normal controls were included.
Results: The blood oxygen level-dependent signal in the orbitofrontal cortex of the brain of heroin-dependent patients was significantly elevated 3 days after the withdrawal. Hyperfunction of the orbitofrontal cortex declined 1 month after the withdrawal.
Conclusion: Heroin-dependent subjects at both 3 days and 1 month abstinence have persistent abnormalities in the brain function. Although some tangible beneficial effects are noted following 1 month of detoxification, possible permanent damage to the brain caused by heroin use is suggested.