The Effect Of Intentional And Incidental Encoding On Emotional Associative Memory: From The Angle Of Directed Forgetting Procedure

In laboratorial condition,the study of associative memory was usually in the manner of intentional encoding,in other words,participants were usually asked to remember the associative information at the time of encoding.But people usually encode associative information incidentally in everyday life.There were few studies discussing the effect of different way of encoding on associative memory of emotional information.Different way of encoding may lead to different effect for emotional associative memory.On the other hand,there were also few studies discussing the effect of post-stimulus encoding on associative memory.According to previous study,directed forgetting procedure had the effect of attentional inhibition(Zacks et al.,1996),and it was a good experiment procedure to control intentional encoding and incidental encoding,and post-stimulus encoding.Different effect of associative memory performance and directed forgetting effect may exist between different interval time of stimulus presentation and indicators.So,the present research studied associative memory of emotional information in intentional and incidental encoding condition,using directed forgetting procedure,for the sake of exploring the influence of different way of encoding in stimulus presentation stage and post-stimulus stage for emotional associative memory.There were two experiments in the present research: experiment 1 studied emotional associative memory in intentional and incidental encoding condition,using mixed experimental design: 2(indicator: remember,forget)× 2(emotional type: negative,neutral)× 2(encoding type: intentional,incidental)(indicator and emotional type are within-subject variable;encoding type was between-subject variable).Negative-negative and neutral-neutral word pairs were used as experiment materials in the present study.On the basis of experiment 1,experiment 2only extended the time between stimulus and indicators(from 2s to 5s)in the same experiment materials and same experiment design,and longer interval time of remember or forget instruction for participants meant they can only have the same encoding between the stimulus and indicators,thus,the effect of post-stimulus encoding time for emotional associative memory can be explored.The recognition correct rate of associative memory in all the conditions were analyzed and the conclusions were as follows:(1)Be different from item memory,in incidental encoding condition,the correct recognition rate of original word pair was still above chance.But,intentional encoding can increase the correct recognition rate of associative memory.(2)Post-stimulus encoding can impair associative memory of directed forgetting effect.(3)Associative memory happened in stimulus presentation stage primarily and also happened in post-stimulus stage.Although post-stimulus encoding can also influence associative memory,there was a time limit.(4)Emotional valence had no effect on the recognition of original between-item associative memory,and the increasing of post-stimulus encoding time may also increase negative emotional between-item associative memory.