Social Reward Processing Of Male Heroin Abstainers

Abnormal reward processing of drug addicts may be a major factor of drug addiction.Abnormal reward processing of drug addicts is manifested by their excessive attention to drugs and drug-related clues and low sensitivity to non-drug rewards(monetary rewards,social rewards,etc.).Although people have carried out corresponding research on the money reward of drug addicts,they have found that there are abnormalities in their processing of money.However,as an important natural reward,there is still a lack of corresponding research.The abnormality of social reward function may be one of the main reasons for the abnormality of social cognition and social behavior of drug addicts.The current research only found abnormal activation patterns of reward brain regions when drug addicts face social rewards.However,reward processing is a time process,and different time stages represent different processing meanings.Therefore,in this study,event related potential,ERP)is used to explore the neural mechanism of social reward processing for heroin addicts from the perspective of time process.In Experiment 1,the social incentive delay task combined with ERP technology was used to explore the neural mechanism of reward expectation and reward feedback in heroin addicts’ social reward processing from the perspective of time process,and then to explore the processing mode of heroin addicts’ social reward.Twenty-eight male heroin abstainers and 27 normal male subjects were selected from an addiction treatment center.The results showed that heroin abstainers’ abnormal social reward processing was mainly manifested in the stage of social reward feedback,that is,there was no significant difference in FRN amplitude induced by good or bad feedback.Similarly,heroin abstainers faced neutral evaluation,and there was no significant difference in P3 amplitude induced by positive evaluation and negative evaluation.Experiment 1 found that heroin abstainers’ social reward processing was mainly manifested in reward feedback stage.Previous studies found that drug addicts’ abnormal financial reward processing could be improved with the increase of withdrawal time.Therefore,experiment 2 still adopts the experimental task of experiment 1,and adopts the method of cross-sectional study to investigate whether there are differences in social reward processing of heroin addicts in different withdrawal periods.Furthermore,it is inferred whether the abnormal social reward processing of heroin addicts will show signs of recovery with the increase of withdrawal time.A total of 81 subjects were selected in the study,including 27 male heroin addicts who had been abstinent for less than six months,27 male heroin addicts who had been abstinent for more than one year,and 27 normal male subjects.The results showed that with the increase of withdrawal time,heroin addicts showed no signs of recovery in FRN amplitude and partial recovery in feedback P3 amplitude,which showed that there was no significant difference between P3 amplitude induced by correct feedback under reward clue,P3 amplitude induced by wrong feedback under reward clue and P3 amplitude induced by feedback without reward clue in heroin addiction group within half a year of withdrawal.In heroin addicts who were abstinent for more than one year,there was no significant difference between P3 amplitude induced by correct feedback under reward clue and P3 amplitude induced by wrong feedback under reward clue.P3 amplitude induced by correct feedback under reward clue was significantly different from P3 amplitude induced by feedback without reward clue.P3 amplitude induced by wrong feedback under reward clue was significantly different from P3 amplitude induced by feedback without reward clue.To sum up,this study found that male heroin abstainers have abnormal social reward feedback processing,and after more than one year of abstinence,the abnormal social reward feedback processing has partially recovered.