The Effect Of Punishment Motivation On Motor Inhibition And Memory Inhibition

Inhibition is one of the most important part of the cognitive control functions,which requires human to control their automatic response tendency or stop one's response when signals changed in some special circumstances.One of the classical paradigm of motor inhibition is the go/no-go(GNG)task,in which participants should make a response to one stimulate while hold on to others.Based on GNG,researchers had developed a memory inhibition paradigm named think/no-think(TNT),to investigate the motivated memory inhibition rather than the passive forgetting.Inhibition tasks require individuals to have enough internal motivation to complete tasks,but the conclusions are controversial about whether the external motivation could improve the performance or not and what their neural mechanisms look like.In addition,there are studies made to compare motor and memory inhibition,in order to find whether they have a similar cognitive mechanism.The present study consists of three experiments,connecting the motor inhibition paradigm namely GNG and memory inhibition paradigm namely TNT each at the first and second experiment.We also conducted the motivation of avoiding punishment,to investigate how external motivation would affect inhibition and its electrophysiological mechanism.In the third experiment,the similarity between two inhibition and the relationship between personality characteristics and behavioral inhibition/activation system are explored by conducting these two experiments in the same subjects,from the perspective of personality psychology.Combined with previous research results,we mainly proposes three hypotheses: 1.The motivation of avoiding punishment can improve individual's motor inhibition ability.2.The motivation of avoiding punishment can improve memory inhibition performances.3.There is a certain similarity between these two inhibition functions in the acquisition of cognitive control mechanism,even if they are effected by motivation.The first research adopts a single factor within subjects design,and the three levels include response condition Go represented by a green frame,normal inhibition condition no-go(NG)represented by a red frame and inhibition-punishment condition NG_S represented by a red frame with a signal of lightning.Twenty-three participants' data are analyzed in our study.Behavioral results show that there is no significant difference among the accuracies of conditions and the ERP analysis reveals four main components: P2(140-190 ms)has the highest amplitude under NG_S condition,suggesting that the higher attention arousal participants had when they saw the lightning.The second component is N2 with a time window of 200-330 ms after stimuli onset,unfortunately,the amplitude value of N2 is lowest under NG condition.We speculated that individuals in this task has a tendency for not making response aimed at avoiding the punishment,so participants would be more accustomed to NG_S condition and experience less conflict monitoring.The third and fourth components belong to P3 family but have different distribution.The former(P3a)with a time window of 340-440 ms and distributed anteriorly,while the latter(P3b)was located in parietal lobe mostly.Specially,the amplitude of P3 a is higher in inhibition condition than that in Go condition,suggesting the inhibition function,but we do not find the motivational effect.At last,the amplitude of P3 b is higher in Go condition,which represents the information processing towards response trials and the key operations.The second study also adopts single-factor within subjects design with four conditions: think condition(T)with a green frame,normal no-think condition(NT)with a red frame,no-think punishment condition(NT_S)with a red frame and a signal of lightning and the baseline condition(B).Twenty-six participants' data are analyzed in this research.In the study phase,participants should learn word-picture pairs until reach a certain accuracy,during the pre-test phase,they were presented by one word with four different pictures and need to choose the correct answer.Later in the TNT phase,when they saw the word on T trials they should try their best to recall its corresponding picture while if they saw the word with red frame,they must stop recalling and if the memories intrude into mind involuntarily they should push them out.If there is a lighting within the frame that means participants will receive an electro punishment if they do not complete the NT introductions.It's worth mentioning that all the real punishment trials were selected manually.The post-test is similar to the pre-test.Our behavioral results show that there is no significant difference among the recall ratio(post-test/pre-test)of four conditions,which means we do not find the negative control effect.From the perspective of response time,that for inhibition trials are longer than that for B trials,suggesting that after continuous memory suppression there is a memory impairment for individuals so it's hard to retrieve pictures.The ERP results also find four main components: P2(130-230 ms)has higher amplitudes under NT_S and T conditions,we speculate that the automatic memory retrieval and memory inhibition under avoiding punishment motivation have a similar effect on the individual's attention.The amplitude of N2(300-400 ms)is significantly lower on NT_S trials than that on NT and T trials,indicating the individuals' efforts to adopt the memory suppression mechanism.We found P3 component with a time window of 310-380 ms in parietal lobe and its amplitude is highest under NT_S condition,reflecting the processing and updating of information,as well as the motivational function.The last one is LPP(450-650 ms)which represents the memory recollection.However,we find no differences between NT_S and T trials,indicating that even if individuals try to suppress their memories,it's hard to induce real forgetting,which is consistent with the behavioral results.In addition,the LPP amplitude is lower on NT trials when compared with NT_S trials,we speculate that memory inhibition under avoiding punishment motivation will induce people to continuously check the inhibitory strategy and result in memory reactivation.In the third study,we choose data of participants involved in both experiments(21 subjects)to analysis their ERP results and collect questionnaires such as NEO-FFI.The results show that the conscientiousness is correlated with BAS and BASF negatively,and the amplitude of P3 under each condition has a positive correlation with BASD.In addition,there is no difference of P2 amplitude between two tasks,indicating that the attention of the participants were consistent,but there is a motivational effect.The amplitude of N2 is more negative on TNT task,so we could say that more inhibition is needed for memory suppression.The P3 b component is influenced by tasks and motivation,which confirms the role of motivation and the need for more complex strategies for memory suppression.In conclusion,this study combines motivation with TNT task and we find the motivational effect successfully.While the inhibitory motor performance is not motivated by avoidance punishment motivation,we speculate that the key response is too simple to make the motivational effect,given the complexity of the task.In addition,this study confirms that there is a common mechanism between motor inhibition and memory inhibition,mainly embodied in the cognitive control function of N2,at the same time we find that the suppression under motivational effect might have overlapped brain locations from the perspective of the electrophysiology,embodied in the motivation and updating information function of P3.Finally,the relationship between the ERP results(P3)and the behavioral inhibition/activation system also provides new evidence for our search for motivation.