Intentional Forgetting Of Negative Materials In Depressed Individuals:the Effect Of Different Training Strategies And Sensory Channels

Objects:(1) the first purpose of this study was to examine whether the efficacy of intentional forgetting differs for directed forgetting and substitution forgetting in depressed individuals.(2) the second purpose was to investigate whether the suppression effect could be obtained by auditory presentation in TNT paradigm.Methods: A total of 74 depressed subjects who were experiencing depressed mood that had lasted for one week and 74 never-depressed control subjects from 1250 Jiangxi Normal University undergraduates participated in the experiment according to the results from Beck Depression Inventory(BDI) and The Center for Epidemiologic Studies Depression Scale(CES-D). Fifty-four depressed individuals and Fifty-four control individuals participated in experiment 1 and twenty depressed individuals and twenty control individuals participated in experiment 2. In experiment 1, participants were trained to forget emotional materials using three different strategies(unaided condition, positive-word substitute, positive-picture substitute) by visual presentation.Subjects who learned the substitutes were instructed to think about the substitute words/pictures instead of thinking about the original pairs, but subjects in the unaided condition were told to “not think” about the associated target and just comprehend the meaning of cue words. The second experiment was to testify the forgetting effect by auditory presentation. Participants first learned each pair from headset, then the test will continue until at least of 50% of the pairs were correctly recalled. In the second phase, subjects were told that when the cues presented by a male voice, they should immediately recall the associated targets word. When the cues presented by a female voice, however, they should suppress the associate word and just comprehend the meaning of cue word. In the final recall test, subjects were asked to recall all the original targets from the first learning phase, regardless of whether they had suppressed or responded to the cue words in the TNT phase.Results:(1) Depressed individuals forgot more negative words than condition individuals in two experiment.(2) All the participants exhibited less recall in the aided group than in the unaided group. However, the suppression effect on strategy of positive-word substitute did notdiffer from the strategy of positive-picture substitute.(3) In experiment 1, although forgetting was enhanced as the suppression time increased, retention of final test in the baseline items was reliably lower than the suppression items to recall targets.(4) In experiment 2, all the participants also showed below-baseline results and there was no difference between twice and eighth in the suppression items.Conclusion:(1) These results indicate that substitutes can help individuals forget more negative materials and the effect of interference by words and pictures has no difference.(2) Emotional materials may interrupt the effects of intentional forgetting in TNT paradigm.