The role of the anterior cingulate cortex in emotional response inhibition

Abstract

Although the involvement of the anterior cingulate cortex (ACC) in emotional response inhibition is well established, there are several outstanding issues about the nature of this involvement that are not well understood. The present study aimed to examine the precise contribution of the ACC to emotion-modulated response inhibition by capitalizing on fine temporal resolution of the event-related potentials (ERPs) and the recent advances in source localization. To this end, participants (N = 30) performed an indirect affective Go/Nogo task (i.e., unrelated to the emotional content of stimulation) that required the inhibition of a motor response to three types of visual stimuli: arousing negative (A-), neutral (N), and arousing positive (A+). Behavioral data revealed that participants made more commission errors to A+ than to N and A-. Electrophysiological data showed that a specific region of the ACC at the intersection of its dorsal and rostral subdivisions was significantly involved in the interaction between emotional processing and motor inhibition. Specifically, activity reflecting this interaction was observed in the P3 (but not in the N2) time range, and was greater during the inhibition of responses to A+ than to N and A-. Additionally, regression analyses showed that inhibition-related activity within this ACC region was associated with the emotional content of the stimuli (its activity increased as stimulus valence was more positive), and also with behavioral performance (both with reaction times and commission errors). The present results provide additional data for understanding how, when, and where emotion interacts with response inhibition within the ACC.

Effects of Emotional Valence on Hemispheric Asymmetries in Response Inhibition

“…Collectively, these studies suggest that conflict monitoring processes are not sensitive to emotion. Also consistent with other studies, we observed that Nogo-P3 was enhanced in the presence of positive emotional stimuli [44,45]. The most common interpretation of emotional potentiation of the P3 is that sustained attentional engagement with positive emotional stimuli affects the execution or evaluation of inhibitory processing.…”

“…Behaviourally, emotional stimuli were associated with marginally better performance on Nogo trials, consistent with a "freezing" effect of emotion, perhaps driven by attentional prioritisation of emotional stimulus processing [50]. Turning to the ERP measures, we found no effect of emotion on the Nogo-N2, consistent with other studies [44,45]. Collectively, these studies suggest that conflict monitoring processes are not sensitive to emotion.…”

“…In contrast, emotional stimuli consistently enhance the Nogo-P3 [46,47,51], with effects sometimes greater for positive than for negative stimuli [44,45]. This enhanced Nogo-P3 is typically interpreted as a more effortful or less efficient inhibitory control in emotional contexts [44,45,48]. Our question concerns the effects of lateralisation of the emotional stimuli on response inhibition processes.…”

“…However, a number of studies have manipulated the emotional nature of imperative stimuli in central vision, while still keeping emotion itself incidental to the task [44][45][46][47][48][49]. The effect of emotion on behavioural measures is mixed across these studies, with some showing more errors on Nogo trials in emotional contexts [50], but most showing no behavioural effects [44,45,49].…”

“…Most studies show no effect of emotion on the Nogo-N2 [44,45,49,51], although some have reported an attenuation of the N2 for emotional relative to neutral stimuli [46,47]. In contrast, emotional stimuli consistently enhance the Nogo-P3 [46,47,51], with effects sometimes greater for positive than for negative stimuli [44,45]. This enhanced Nogo-P3 is typically interpreted as a more effortful or less efficient inhibitory control in emotional contexts [44,45,48].…”