Temporal Characteristics of the Three Stages of Intentional Inhibition
Behavioral inhibition can be categorized into reactive inhibition and intentional inhibition.Several studies have used the free-choice task(e.g.,the Go/No-go/Choose task)to investigate the temporal dynamics of intentional inhibition,but have reported inconsistent findings.The present study aims to develop a novel task(i.e.,the Free Two-Choice Oddball Task)and re-evaluate the temporal dynamics of intentional inhibition.Thirty-seven female undergraduates were recruited to perform the Free Two-Choice Oddball task,in which free choice trials were integrated with conventional Two-Choice Oddball task(including Reactive Standard trials and Reactive Deviant trials).They were asked to press button"1"for Reactive Standard trials,button"2"for Reactive Deviant trials,and intentionally choose to press button"1"or"2"for free choice trials.To ensure a prepotent drive to press button"1",the Reactive Standard trials,Reactive Deviant trials,and Intentional trials(i.e.,free choice trials)were set at a ratio of 4∶1∶2.In formal task,714 trials were divided into 6 blocks of 119 trials each.Behavioral data and event-related potentials(ERPs)were recorded while participants performing the task.For ERP data,N2 and P3 components were focused.For N2,the fronto-central electrodes(Fz,FC1,FC2,FCz,Cz)were selected as the region of interest,and the average amplitudes were measured in the 240～300 ms time window.For P3,the central-parietal electrodes(C1,C2,Cz,CP1,CP2,CPz,P1,P2,Pz)were selected,the early P3 amplitudes were measured in the 300～440 ms time window,and the late P3 amplitudes were measured in the 460～700 ms time window.Moreover,to further differentiate between early and late P3 components,a temporal principal component analysis(PCA)was conducted,the electrodes are the same as above,and the time windows for PCA early P3 and PCA late P3 were 380～460 ms and 530～640 ms respectively.At the behavioral level,the Action Source(Reactive,Intentional)x Stimulus category(Standard,Deviant)ANOVA on response times(RT)showed a significant interaction effect.Further analyses showed that,for both the Reactive and Intentional conditions,the Deviant stimuli were associated with longer RTs than the Standard stimuli.Moreover,the Intentional condition showed longer RTs than the Reactive condition for Standard stimuli,but the opposite pattern was observed for Deviant stimuli.At neural level,the Action source(Reactive,Intentional)x Stimulus category(Standard,Deviant)ANOVA on N2 amplitudes only showed a significant main effect of Action source,with more pronounced amplitudes for the Intentional condition than for the Reactive condition.For the traditional averaged early P3 component,the ANOVA only showed a significant main effect of Stimulus category,with larger amplitudes for the Deviant stimuli than for the Standard stimuli.Meanwhile,the analysis on PCA early P3 component showed a significant interaction effect.Further analyses showed that,for both the Reactive and Intentional conditions,the Deviant stimuli elicited larger amplitudes than the Standard stimuli.Moreover,the Intentional condition showed larger amplitudes than the Reactive condition for Standard stimuli,but a reverse pattern was observed for Deviant stimuli.For the late P3 component(both the traditional and PCA results),the ANOVA showed a significant interaction effect.Further analyses showed that,for the Reactive condition,the Deviant stimuli elicited larger amplitudes than the Standard stimuli,while for the Intentional condition,the Deviant stimuli elicited smaller amplitudes than the Standard stimuli.Moreover,the Intentional condition showed larger amplitudes than the Reactive condition for Standard stimuli,but a reverse pattern was observed for Deviant stimuli.Finally,correlation analyses revealed negative associations between the RT and ERP indices of intentional inhibition,including RT delay,N2 differences,and early P3 differences(i.e.,the differences between Intentional Deviant stimuli and Intentional Standard stimuli,both the traditional and PCA results).However,only a significant negative correlation was found between the inhibition rate and RT delay,while no significant correlations were observed between the inhibition rate and ERP indices of intentional inhibition.In summary,the present study suggests that the temporal dynamics of intentional inhibition may encompass the updating of a current and well-prepared response program(indicated by the N2 component),the implementation of inhibitory performance(indicated by the early P3 component),and the subsequent evaluation of inhibitory performance(indicated by the late P3 component).Moreover,these findings also indicate that the Free Two-Choice Oddball task not only captures neural activity associated with intentional inhibition but also provides behavioral evidence for this cognitive process(specifically,the updating process and the implementation of inhibitory performance),making it a more suitable research paradigm in this field.
万方数据
维普
