The Effect And Mechanism Of Positive Mental Imagery-based Episodic Simulation On Depression And Anticipatory Pleasure

Objectives:(1)To examine differences between depressed and non-depressed individuals in their ability to experience anticipatory pleasure,and between features of episodic future thinking about positive future events associated with the individual(i.e.,detail/vividness,use of imagery,use of a first-person perspective,likelihood of the event,the time since the event,importance and specificity of the event to the individual);(2)Multiple linear regression was used to explore the extent to which the features of positive future events related to the individual predicted the predictive ability of anticipatory pleasure in depressed individuals;(3)The positive mental imagery-based episodic simulation was used to explore the effectiveness and mediating mechanism of positive mental imagery-based episodic simulation on the episodic future thinking and anticipatory pleasure of depressed individuals,as well as the effectiveness of positive mental imagery-based episodic simulation on reducing the level of depression and improving behavioral activation of depressed individuals.Methods:(1)In study 1,participants with PHQ-9 score greater than 5 points,BDIII scale score greater than 14 points and HAMD-17 score greater than 7 points were screened,or participants with PHQ-9 score less than 5 points,BDI-II scale score less than 14 points and HAMD-17 score less than 7 points completed the Episodic Future Thinking Test(EFT-T)and the Temporal Experience of Pleasure Scale(TEPS).Difference test and regression analysis were performed on the results.(2)In study 2,participants with PHQ-9 scores greater than 5 points and BDI-II scale scores greater than 14 points were screened and interviewed one by one by graduate students of clinical psychology using Hamilton Depression Scale(HAMD-17).Participants with HAMD-17 score greater than7 points were randomly assigned to the imagery group(30participants),reasoning group(30 participants),and wait-control group(30 participants)to complete The Behavioral Activation for Depression Scale(BADS),the Temporal Experience of Pleasure Scale(TEPS),and the Episodic Future Thinking Test(EFT-T).Different intervention methods were used to conduct mental imagery-based episodic simulation and cognitive reasoning intervention for the mental imagery group and the reasoning group,once a week,twice in total.The pre-test(t1)and post-test(t2)were conducted before and after the intervention,and the follow-up was conducted twice one month later(t3)and two months later(t4).Results:(1)Compared with the non-depressed group,individuals in the depressed group had significantly lower anticipatory and consummatory pleasure(p<0.001),less detail/vividness of future thinking about personally relevant positive events scenarios,less use of mental imagery,less use of a first-person perspective,less likelihood of events occurring,and longer time since now,less important and less specific to individuals(p<0.001);(2)After controlling for the degree of depression,the features of positive event future thinking in depressed individuals accounted for 32.9% of the total variation and 86.3% of the total variance explained by the model;(3)With PHQ-9 score,BDI-II score,Temporal Experience of Pleasure Scale score(including consummatory pleasure and anticipatory pleasure)and The Behavioral Activation for Depression Scale score as dependent variables and group and time as independent variables,repeated measurement analysis of variance found that the group and time had significant main effects and significant interaction.The variables of the wait-control group did not differ significantly at each time point.The PHQ-9 scores and BDI-II scores of mental imagery group and reasoning group were significantly lower at t2 than at t1,but there was no significant difference at t2,t3 and t4.BADS score of the mental imagery group was significantly lower than that of t1 at t2,and there was no significant difference at t2,t3 and t4.There was no significant difference between the inference group at each time point.At t2,the scale score of the mental imagery group was significantly greater than that of t1,t3 and t4,while that of the reasoning group was significantly greater than that of t3 and t4.In the,mental imagery group,the score of the TEPS-A was significantly greater than that of t1,t3 and t4 at t2,while that of the reasoning group was significantly greater than that of t3 and t4 at t2.The scores of the wait-control group and the reasoning group were significantly higher at t1 than at t3 and t4.(4)The scores of the features of episodic future thinking(i.e.,details/vividness,use of imagery,use of firstperson perspective,possibility of the event,time from the present,importance and specificity of the event to the individual)of positive future events were taken as dependent variables,and the group and time were taken as independent variables.In the mental imagery group,the details/vividness of future thinking,the use of imagery,the use of first-person perspective,the possibility of the event,the time since now and the importance to the individual were significantly different before and after the intervention,but the specificity was not significantly different;There was no significant difference between the reasoning group and the wait-control group in the episodic future thinking features of positive future events.(5)The use of imagery,vividness and the first-person perspective of episodic future thinking played a completely mediating role in the imagery intervention and anticipatory pleasure;Anticipatory pleasure did not mediate between imagery intervention and depression level.Anticipatory pleasure did no mediating between imagery intervention and behavioral activation.Conclusion:(1)Compared with the non-depressed group,the depressed group had significantly lower anticipatory and consummatory pleasure,less detail/vividness of the episodic future thinking of positive events related to the individual,less use of mental imagery,less use of the first-person perspective,less likelihood of events occurring,longer time since now,less importance to the individual,and less specificity;(2)The details/vividness of episodic future thinking of positive events,the use of imagery,and the use of first-person perspective can significantly predict the anticipatory pleasure of depressed individuals;(3)The positive mental imagery-based episodic simulation can improve the episodic future thinking,anticipatory pleasure and behavioral activation of positive events in depressed individuals,reduce the level of depression,and maintain the effect for a long time;(4)The use of imagery,vividness and first-person perspective of episodic future thinking played a complete mediating role in imagery intervention and anticipatory pleasure,that is,the positive imagery intervention can improve the anticipatory pleasure of depressed individuals by improving the use of imagery,vividness and first-person perspective of episodic future thinking of positive events.