Impact Of Aerobic Exercise On Drug Craving Of Male Methamphetamine-dependent Patients And Cognitive Neural Mechanisms

The abuse and addiction of illegal drugs has long become a medical and social problem that needs to be solved urgently.Recent theories believe that drug addiction is a response inhibition and salience attribution deviation caused by the damaged prefrontal cortex.Due to the dysfunction of the prefrontal cortex,the normal operation of the frontal lobe-basal ganglia pathway is disrupted.With the weakening of executive function,individuals cannot effectively suppress the impulse approach to drugs.It was also generally reported that the defect in behavioral executive function is the important psychological basis that leads to the maintenance of addictive behavior patterns and relapse after withdrawal.Hence,enhancing the executive function of is critical for improving the success rate of withdrawal treatment.Numerous studies have shown that aerobic exercise can effectively enhance brain function,indicating that it is feasible to repair the impaired executive function of drug-dependent patients through aerobic exercise to reduce drug craving and relapse behavior.At present,researchers have found that moderate-intensity aerobic exercise can significantly improve the response inhibition of methamphetamine(MA)-dependent patients and relieve drug craving.However,for other sub-components of executive function,research on the role of conflict inhibition and working memory in the effect of aerobic exercise on drug craving is still lacking.The defect of conflict inhibition can predict the relapse behavior after withdrawal,which is the key to affecting withdrawal treatment.Working memory is also closely related to relapse behavior,and severely impaired individuals are more likely to be interfered by repeated drug use behaviors and affect withdrawal effect.Therefore,it is necessary to understand the effects of aerobic exercise on conflict inhibition and working memory in drug-dependent patients,and its relationship with reducing drug cravings.According to existing research,aerobic exercise can increase brain blood oxygen content during exercise to enhance brain activity and promote the improvement of executive function.Previous studies also suggest that in healthy people,the increase in cerebral blood oxygen content caused by aerobic exercise will be intensity-dependent in the prefrontal cortex.The exercise intensity increases,the neuronal activity in the brain will also increase.However,in drug-dependent patients with damaged prefrontal cortex,whether there is still a positive relationship between exercise intensity and exercise effect still needs to be clarified.In addition,existing studies mostly use moderate-intensity aerobic exercise intervention,while the effect of high-intensity aerobic exercise on drug-dependent patients and cognitive mechanism are still unclear.The effect of different cortical processing caused by different intensity exercise on executive function,and the degree of change in drug craving is still needs to be studied.Thus,this study intends to use three studies to discuss the above-mentioned issues.First target is to study the changes in the blood oxygen response of the prefrontal cortex.The study used functional near-infrared spectroscopy(f NIRS)to investigate the difference in the activity of the prefrontal cortex in MA-dependent patients caused by different intensity aerobic exercise from the basic neural mechanism.The results showed that for MA-dependent patients,the level of hemodynamic changes in the prefrontal cortex trend to increase significantly during high-intensity acute aerobic exercise compared to moderate intensity.Then,the effects of different intensity aerobic exercise on reducing drug craving were explored from the dual perspectives of external behavior and internal cortical activity.Although the results did not found the positive effect of acute aerobic exercise on drug craving,acute high-intensity exercise could increase the level of nerve activity in some ventrolateral and dorsolateral prefrontal lobes,while moderate intensity has no significant effect.Finally,the study investigate the moderation effects of conflict inhibition and working memory updating in the process of long-term aerobic exercise affecting drug cravings,in order to explore the cognitive neural mechanism of aerobic exercise affecting drug craving.The results showed that high-intensity long-term aerobic exercise can significantly reduce drug cravings and improve working memory updating levels in MA-dependent patients by enhancing the neuronal activity of the left dorsolateral prefrontal brain area,while moderate-intensity exercise intervention has no significant effect.Moreover,working memory updating has a modulation effect on the influence of aerobic exercise on drug craving.For patients with improved working memory updating,long-term aerobic exercise has a significant negative predictive effect on changes in drug craving,and the greater the exercise intensity is,the lower drug craving is.The above results showed that compared with moderate-intensity,high-intensity aerobic exercise can better improve prefrontal cortical nerve activity during exercise and working memory updating for MA-dependent patients,and reduce their drug cravings.In addition,working memory can significantly regular the degree of aerobic exercise on drug craving.For patients with improved working memory updating,higher exercise intensity can more effectively alleviate their drug cravings.The difference in hemodynamic changes of the left dorsolateral prefrontal cortex caused by exercise of different intensities may be an important neural mechanism.