Brain Dynamics Underlying Training-Induced Improvement in Suppressing Inappropriate Action

Abstract

Inhibitory control, a core component of executive functions, refers to our ability to suppress intended or ongoing cognitive or motor processes. Mostly based on Go/NoGo paradigms, a considerable amount of literature reports that inhibitory control of responses to "NoGo" stimuli is mediated by top-down mechanisms manifesting ϳ200 ms after stimulus onset within frontoparietal networks. However, whether inhibitory functions in humans can be trained and the supporting neurophysiological mechanisms remain unresolved. We addressed these issues by contrasting auditory evoked potentials (AEPs) to left-lateralized "Go" and right NoGo stimuli recorded at the beginning versus the end of 30 min of active auditory spatial Go/NoGo training, as well as during passive listening of the same stimuli before versus after the training session, generating two separate 2 ϫ 2 withinsubject designs. Training improved Go/NoGo proficiency. Response times to Go stimuli decreased. During active training, AEPs to NoGo, but not Go, stimuli modulated topographically with training 61-104 ms after stimulus onset, indicative of changes in the underlying brain network. Source estimations revealed that this modulation followed from decreased activity within left parietal cortices, which in turn predicted the extent of behavioral improvement. During passive listening, in contrast, effects were limited to topographic modulations of AEPs in response to Go stimuli over the 31-81 ms interval, mediated by decreased right anterior temporoparietal activity. We discuss our results in terms of the development of an automatic and bottom-up form of inhibitory control with training and a differential effect of Go/NoGo training during active executive control versus passive listening conditions.

Plastic modifications within inhibitory control networks induced by practicing a stop-signal task: An electrical neuroimaging study

“…This pattern contrasts with previous evidence for the development of automatic, feed-forward forms of inhibition induced by training with a Go/NoGo task (Manuel et al, 2010). This difference in the effect of practice with an SST versus a Go/NoGo task likely follow from the fact that in SST task, Go stimuli are inconsistently associated with Go and NoGo goals, whereas in Go/NoGo task, repeated associations between NoGo stimuli and NoGo goals enable the development of stimulus-driven inhibition (Shiffrin and Schneider, 1977;Verbruggen and Logan, 2008a).…”

“…While inhibitory control has been extensively studied (Chambers et al, 2009;Aron, 2011), the behavioral and brain plastic changes induced by practicing inhibition tasks remain largely unresolved. Manuel et al (2010) demonstrated that training on a Go/ NoGo task improved inhibitory control performance, but that the behavioral improvement was not supported by a modification of the global frontoebasal inhibitory control network. Rather, neuroplastic changes manifested within temporoparietal cortices over the initial stages of the processing of the stimuli, indicative of the development of stimulus-driven, feed-forward forms of inhibition directly triggered by the NoGo stimuli (Manuel et al, 2010;Shiffrin and Schneider, 1977).…”

“…A topographic pattern analysis was applied to the ERPs to determine whether the configuration of intracranial generators changed between the beginning and the end of the practice (e.g., Michel et al, 2004;Murray et al, 2008;Manuel et al, 2010Manuel et al, , 2012. This approach is based on evidence that the ERP map topography does not vary randomly across time, but remains quasi-stable over 20e100 msec functional microstates before rapidly switching to other stable periods (Lehmann and Skrandies, 1980;Britz and Michel, 2011).…”

“…SSTs consist in speeded discrimination tasks in which responses to the stimuli have to be canceled when a stop signal is presented (Logan and Cowan, 1984). By contrast to the Go/NoGo task used in Manuel et al (2010), stimulus-response mappings are inconsistent in the SST (each Go stimulus is associated with activation or with inhibition goals). Therefore, automatic inhibition would unlikely develop during SST practice, and the frontoebasal inhibitory control network would be constantly involved (Verbruggen et al, 2008a) and in turn strengthened.…”

Enhancing frontal top-down inhibitory control with Go/NoGo training

“…Inhibitory control (IC), the ability to suppress ongoing or planned cognitive or motor processes, can be improved with short-(50 min in Verbruggen and Logan 2008;Manuel et al 2010;Manuel et al 2013) to medium-term training (ca. 10-15 h in Thorell et al 2009;Johnstone et al 2012;Berkman et al 2014;Chavan et al 2015).…”