Study Of Brain Functional Changes In Craving State By Visual Cue-Induced On Heroin Addicts

Craving, a strong desire for more drug experience with central action to drug addicts, is not only a drive but also a compulsive demand, can manipulate drug addicts' mind, influence his emotion, restrict his behavior, and maintain for a long time, and this is an important factor to lead to relapse. The key factors that influence craving include protracted withdrawal symptoms, drug doses, drug-taking time, and the ways of abuse. Now the researches have found three ways of stimulation may induce relapse: 1) relative conditioned cue, 2) drug, 3) stress, and demonstrated that drug relative cues could induce drug addicts craving at home and abroad.Objective: 1) Investigate the craving induced by self-edited silent visual cues on heroin addicts and evaluate the reliability and validity of these cues. 2) Study the changes of self-report scores, Galvanic skin responses (GSR), electroencephalogram (EEG) brain electrical activity mapping (BEAM) and autonomic nervous response (ANS) patterns in different craving states induced by different cues. 3) Observe the changes in forms and function of brain through function magnetic resonance imaging-blood oxegenation level dependence (fMRI-BOLD) and the location of relative functional brain area in heroin addicts. 4) Explore the relevance in brain-electrical signal changes and biological and psychological responses, and craving and drug addiction mechanism, finally provide the evidence of theory and experiment for preventing relapse and methods of detoxification.Method: Case-control study. The age, gender and cultural background matched between two-group subjects. Subjects would be excluded who could not express their feelings measured by Toronto Alexithymia Scale (TAS). Two groups of subjects were presented with different cues, including natural scenery and heroin relative films: 1) administrated two questionnaires (Likertscale and craving sense scale) to obtain self-report craving scores to evaluate the craving; 2) recorded the changes of BEAM, GSR, physiological index (blood pressure, respiration rate, heart rate, heart rate variability, difference in pulse pressure) which may indicate the automatic nerve functions; 3) adopted fMRI-BOLD technology to study the changes of forms and function on relative brain areas and its location.Result: (1) The difference of craving scores was significant when heroin group were presented with different cues(p<0.001),but with no difference in control group(p>0.05); There was significant difference in craving scores when heroin group and control group were presented with heroin-relative cues and neural cues, respectively.(2) GSR was different between two groups presented with different cues. Compared with control group, spectral power values of GSR in heroin group grew remarkably and oscillogram changed obviously.(3) Physiological index changes manifested differences between two groups presented with different cues. Heroin group subjects showed that the mean value and maximum of R-R rate increased, high spectrum power of heart rate variation (HRV) promoted, and systolic blood pressure was higher and respiratory frequency speed up mildly, there was no significant difference in the control group subjects.(4) EEG and BEAM: When presented with the different cues, the control group subjects showed no obvious brain regional activation and no significant changes in brain electric spectral power values at the same measurements. When presented with the heroin-related cues, Control group subjects had a trend of slow waves decrease and fast waves increase, especially the 8 waves decrease. There was no significant difference in the craving scores of self-reported and the GSR between two sessions (p>0.05). In heroin group, brain electric spectral power values grew in all the leads, the left lateral frontal lobe, central lobe, parietal lobe and part of temporal lobe were all activated, so were right lateral part of frontal lobe and parietal lobe and companied with slow waves increasing and fast waves decreasing trend, especially 9 wave increased. There was significant difference in the craving scores of self-reported and GSR between two sessions (p<0.05).