Release From Proactive Inhibition In Divergent Thinking Tasks

Proactive interference(PI)refers to a phenomenon that memory for recently studied information can be vastly impaired by the previous studied information.Many previous studies shown that a subject was presented several trials of word triads drawn from a single semantic category and it was found that performance declined over these trials due to a build-up of proactive inhibition.However,if the semantic category was changed or shifted on the last trial,performance improved significantly,indicating release from proactive inhibition(RPI).To our knowledge,it was the first time that the RPI paradigm in memory research was applied to divergent thinking tasks.In the present study,we used three different divergent thinking tasks including the Alternate Use Task(AUT),the Word Generation Task(WGT)and the Object Association Task(OAT),in which the goal was to generate many different possible solutions to a problem.All tasks were scored for four indicators including repetitive rate,originality,uniqueness and fluency.The present study aimed to examine whether PI and RPI exist in divergent thinking tasks.The goal of the Experiment 1 was to investigate whether or not the shift of the semantic distance would resulted in RPI.Participants were asked to completed the AUT and the WGT.Both of the two tasks were designed as 2(experimental conditions: control group,experimental group)×4(experiment trials: Trial1,Trial2,Trial3,Trial4)two-factor mixed design.In the control group,all targets of four trials were with close semantic distance.In the experimental group,the semantic distance was shifted on Trial4 and the Trial4 target was with the remote semantic distance from the first three targets.The results showed that there was a typical decrease in task performance over the first three trials in two groups due to a build-up of PI.However,in the experimental group,the performance on repetitive rate,originality and uniqueness of the AUT and the performance on repetitive rate,originality,and fluency of the WGT were significantly increased on Trial4 and RPI appeared.Experiment 1 indicated that the shift in semantic distance resulted in RPI in divergent thinking tasks.On the basis of Experiment 1,Experiment 2 aimed to further examine whether the magnitude of shift in the semantic distance reflected in the degree of RPI.According to the degree of change in the semantic distance,we distinguished the remote distance group and the close distance group in the Experiment 2.Participants were also asked to completed the AUT and the WGT and each task was used a 3(experimental conditions: baseline group,close distance group,remote distance group)×4(experiment trials: Trial1,Trial2,Trial3,Trial4)two-factor mixed design.The results of Experiment 2a showed that the originality and uniqueness scores of the AUT and the repetitive rate and fluency scores of the WGT were significantly increased on Trial4 in both the remote distance group and the close distance group,and RPI appeared.Moreover,there was no significant difference in the degree of RPI between the two groups.However,according to the participants' rating of the semantic distance,it was found that there was no significant difference in the semantic distance between the remote distance group and the close distance group of the AUT in the Experiment 2a.Thus,we strictly controlled the difference in the semantic distance between the remote distance group and the close distance group in the Experiment 2b.The results of Experiment 2b showed that the originality of the AUT as well as the repetitive rate and fluency of the WGT still showed RPI in the two groups.And there was no significant difference in the degree of RPI between them.In other words,although the magnitude of change of the semantic distance in the remote semantic distance group was bigger than the remote semantic distance group,the degree of RPI had no significant difference between them.Thus,the results of Experiment 2a and Experiment 2b consistently illustrated that the magnitude of change in the semantic distance has no effect on the degree of RPI.The purpose of the Experiment 3 was to explore whether or not RPI occurred again when the semantic distance changes again.In the Experiment 3,we expanded the experiment trials from four to six and used the OAT instead of WGT.Participants were asked to completed the AUT and the OAT.Each task was designed as 2(experimental conditions: control group,experimental group)×6(experiment trials: Trial1,Trial2,Trial3,Trial4,Trial5,Trial6)two-factor mixed design.In the control group,all targets of six trials were with close semantic distance.In the experimental group,the first three targets were with close semantic distance,then on Trial4 and Trial6 they were shifted to remote semantic distance,and Trial5 was shifted back to the close semantic distance with the first three targets.The results showed that in the experimental group,the repetitive rate,originality and uniqueness of the AUT and the repetitive rate,originality,and fluency of the OAT were significantly increased on Trial4 and Trial6,and decreased again on Trial5.That is to say,RPI occurred on both Trial4 and Trial6 because of the shift of semantic distance,and reappeared PI on Trial5.On the one hand,the results of Experiment 1 were replicated in the Experiment 3.On the other hand,it was fuether shown that RPI would occur again when the semantic distance shifted again.In summary,the present study shows that:(1)In the three divergent thinking tasks of AUT,WGT and OAT,the targets are with close senmantic distance for the first three trials and it is found that the performance declines over these trials due to a build-up of PI.(2)When the semantic distance is shifted,the performance improves and appeares RPI.Moreover the magnitude of shift in the semantic distance has no effect on the degree of RPI.(3)After the first change in semantic distance resulting in RPI,when the semantic distance changes again,RPI will be triggered again.(4)RPI is mainly found in the repetitive rate,originality and uniqueness of the AUT.But it mainly occurs in the repetitive rate,originality and fluency of the WGT and the OAT.