Characteristics Of Risk Decision-making And Moral Decision-making In Heroin Addicts:a Study Combined With Functional Near-infrared Spectroscopy(fNIRS)

Objective:Combining personality,behavior and neurophysiological mechanism,this study explored the difference of decision-making characteristics between heroin addicts and normal subjects.Methods:34 heroin addicts were selected from outpatient department of a hospital in Guiyang,and 35 normal subjects matched by gender,age and education level were selected through community recruitment.The experiment consisted of two parts :(1)the Melbourne Decision Making Questionnaire(MDMQ)was used to measure the decision-making style;The Balloon Analogue Risk Task(BART)and Moral Dilemma Task were used to measure Risk decision and Moral decision behavior respectively.(2)functional Near-Infrared Spectroscopy(f NIRS)was used to was used to investigate the differences in the activation levels of prefrontal cortex(PFC,includi ng ventrolateral prefrontal cortex(VLPFC),dorsolateral prefrontal cortex(DLPFC),orbital frontal cortex(OFC)and frontal pole cortex(FPA))between heroin addicts and normal subjects during risk and moral decision making.Results:(1)Heroin addicts scored significantly higher in the buck-passing dimension of MDMQ than normal subjects(t=2.32,P<0.05).The number of exploded balloons and the number of unexploded balloon buttons of heroin addicts on BART were significantly higher than those of normal subjects(t=3.96;t=4.59,P values were all <0.001);The percentage of utilitarian choice of moral dilemma task in heroin addict group was significantly higher than that in normal group(F=11.52,P<0.05),Self-involved condition was significantly higher than non-self-involved condition(F=4.45,P<0.05);(2)The activation degree of some regions of VLPFC(channel 1 and20),some regions of OFC(channels 4,11 and 13)and some regions of FPA(channel12)in heroin addict group was significantly lower than that in normal group(P values were all < 0.05);In moral decision making,the group main effect was significant in the activation degree of part of DLPFC(channel 2)(P<0.05),and the situation type main effect was significant in the activation degree of part of OFC(channel 11)(P<0.05).The interaction between group and situation type was significant in the activation degree of some VLPFC regions(channels 18 and 20),some OFC regions(channels 13 and 19),and some FPA regions(channels 6,12,14 and 16)(P values were all < 0.05).Conclusions:Heroin addicts tend to have a more blame-passing decision-making style;Heroin addicts were more inclined to risk seeking in risk decision-making and utilitarian choice in moral decision-making.The activation of some regions VLPFC,OFC and FPA in heroin addicts was significantly lower than that in normal subjects.The activation of some regions of DLPFC in heroin addicts was significantly lower than that in normal subjects,and the activation of some regions of VLPFC and FPA in self-involved moral situations was significantly lower than that in non-self-involved moral situations.