The Influence Of Alcohol Use On Emotional Attentional Bias And Its Neural Mechanism

Alcohol and drinking have become an indispensable part of human social life.With the increase of the total amount of alcohol use in the world,the problem of alcohol use has become more and more obvious.Unsuitable alcohol use behaviors have caused many problems to individuals,others and society.Alcohol impairs many cognitive functions of individuals,including cognitive control,memory,and social cognition.Alcohol can also affect emotional processing,and emotional attention is an important part of emotional processing.In the existing studies about acute alcohol,different doses of alcohol have different effects on the cognitive function of individuals.In addition,in social life,alcohol is often associated with problems such as impulsiveness,violent behavior,and criminal cases.The essence of alcohol is that alcohol changes the normal processing of emotional stimuli.Information attention and comprehension,which leads to poor social interaction behavior.Therefore,exploring the natural mechanism of alcohol’s influence on emotional attention helps to understand and reduce the possibility of harmful social behaviors.Analyzing the effect of alcohol dose helps to understand the conditions for bad drinking behavior,and studying the neural basis of alcohol effects can be more clearly to find the target areas of alcohol effects and the relationship between the cognitive functions and emotional processing related with these brain regions.On the other hand,heavy drinking individuals show obvious abnormalities in emotional processing.Therefore,the results of this study will help to improve treatment content towards alcohol use disorders.The results of this study will answer three questions:(1)whether acute alcohol use affects emotional attentional bias;(2)whether there are differences in the effects of different doses of alcohol on emotional attentional bias;(3)alcohol affects emotional attentional bias through which neural mechanism.In Study 1,the within-subject experimental design was used,and the drinking conditions were randomized,and the alcohol conditions were set as placebo,0.3g alcohol/Kg and 0.5g alcohol/Kg.After drinking,the subjects had to complete the emotional word Stroop task designed by Block.The emotional categories of stimuli in the task included neutral,positive and negative emotional words.The aim of the study was to investigate the effect of acute alcohol use on emotional attentional bias and whether this effect varies with the dose of alcohol used.The change of individual emotional attention bias was reflected by the reaction time and accuracy rate.The results of repeated measures ANOVA of alcohol dose and emotion type(3×3)found that:(1)The main effect of alcohol dose was significant when the accuracy rate was used as the index,The accuracy rate of the task response decreased significantly after drinking,and the error rate also increased significantly with the increase of the alcohol dose;(2)Taking the response time as the index,the interaction effect was significant;in the simple effect analysis,under the condition of low-dose alcohol,individuals responded faster to negative emotional words than to neutral and positive emotional words;under moderatedose alcohol conditions,individuals responded slower to positive emotional stimuli than to neutral and negative emotional words.The results of the study show that the patterns of emotional attention bias are different under different alcohol doses.Alcohol use affects the behavioral response of emotional attention bias.Low dose of alcohol use caused individuals to avoid negative stimuli,while medium dose of alcohol use caused difficulty shifting attention to positive emotional stimuliStudy 2 and Study 3 are to further explore the neural basis of behavioral outcomes in Study 1.In Study2,the within-subject experimental design as in Study 1 was also used to perform the same emotional word Stroop task,and the alcohol conditions were set as placebo and 0.3g alcohol/Kg.Due to the higher dose of alcohol,the subjects’ body response is not suitable for testing in MRI equipment,so Study 2 mainly focuses on the differences in the brain mechanism of emotional attention bias under low-dose alcohol and placebo conditions,and the neurophysiological indicators of the study focus on brain activation.The results of repeated measures ANOVA of alcohol dose and emotion type(2×3)found that:(1)the interaction between alcohol dose and emotional type was significant;(2)the results of post-hoc comparison showed that compared with placebo condition,alcohol use increased activity in the middle frontal gyrus,superior frontal gyrus,postcentral gyrus,anterior cingulate gyrus,middle occipital gyrus and thalamus when processing positive emotional stimuli;when processing negative emotional stimuli,alcohol use enhanced precuneus activation.Alcohol use suppressed activity in the middle frontal,superior frontal,middle occipital,and middle temporal gyri when processing neutral stimuli.The results of the study showed that low-dose alcohol enhances the brain areas activity related to emotional stimulus processing but inhibited the semantic processing brain area activity,indicating that alcohol enhanced the attention to irrelevant information such as emotion.This may enhance the emotional sensitivity and interfere with purposive task responses.Study 3 explored the neural basis of the emotional attention bias of moderate dose of alcohol.Due to the high ecological validity of near-infrared spectral imaging technology,the environment is more open than that of nuclear magnetic equipment,and it is more friendly to subjects who have strong physical reactions caused by moderate dose of alcohol.So this imaging technique was used to analyze the differences in neural activity of emotional attention bias under the conditions of placebo and 0.5g alcohol/Kg,and the subjects completed the same emotional word Stroop task when recording near-infrared data.The results of repeated measures ANOVA of alcohol dose and emotion type(2×3)found that:(1)the main effect of alcohol was significant,specially,the activation of the occipital lobe area was enhanced after moderate dose of alcohol use compared with the placebo condition;(2)interaction result of alcohol dose and emotional type were significant,with alcohol use suppressing activity in the bilateral infratemporal cortex compared to the placebo condition when processing positive emotional stimuli.These findings indicated that higher doses of alcohol can inhibit the processing of emotional stimuli,mainly positive emotional stimuli,interfering with the understanding of positive information and reducing the ability to feel positive emotions.The overall results of the three studies showed that:(1)acute alcohol use will reduce the individual’s inhibitory control ability,and the higher the alcohol dose used,the greater the reduction in the individual’s inhibitory control ability;(2)low-dose alcohol use enhanced the attention and processing of emotional stimuli,but inhibited the semantic understanding of neutral words;(3)moderate dose of alcohol inhibited the processing of positive emotional words,affecting the semantic understanding of positive emotional information.In summary,the results of behavioral and neurophysiological experiments in this study explain the impact of acute alcohol use on emotional attentional bias,and provide a more fundamental perspective on how alcohol affects emotional processing.Acute alcohol use leads to abnormal emotional processing by affecting emotional attentional bias.The reason for the increased irritability and harmful behavior of individuals after drinking may be that alcohol affects the attention and understanding of emotional information in the environment.There is no safe level of alcohol use,and even low-dose alcohol can have a noticeable effect on emotional processing.The results of this study also suggest that adding content related to emotion regulation in the treatment of alcohol use disorders can promote the treatment effect.