Pinning down response inhibition in the brain — Conjunction analyses of the Stop-signal task

Center for Cognitive Neuroscience, Duke University, Durham, NC 27708, USA.
NeuroImage (Impact Factor: 6.36). 05/2010; 52(4):1621-32. DOI: 10.1016/j.neuroimage.2010.04.276
Source: PubMed

ABSTRACT Successful behavior requires a finely-tuned interplay of initiating and inhibiting motor programs to react effectively to constantly changing environmental demands. One particularly useful paradigm for investigating inhibitory motor control is the Stop-signal task, where already-initiated responses to Go-stimuli are to be inhibited upon the rapid subsequent presentation of a Stop-stimulus (yielding successful and unsuccessful Stop-trials). Despite the extensive use of this paradigm in functional neuroimaging, there is no consensus on which functional comparison to use to characterize response-inhibition-related brain activity. Here, we utilize conjunction analyses of successful and unsuccessful Stop-trials that are each contrasted against a reference condition. This conjunction approach identifies processes common to both Stop-trial types while excluding processes specific to either, thereby capitalizing on the presence of some response-inhibition-related activity in both conditions. Using this approach on fMRI data from human subjects, we identify a network of brain structures that was linked to both types of Stop-trials, including lateral-inferior frontal and medial frontal cortical areas and the caudate nucleus. In addition, comparisons with a reference condition matched for visual stimulation identified additional activity in the right inferior parietal cortex that may play a role in enhancing the processing of the Stop-stimuli. Finally, differences in stopping efficacy across subjects were associated with variations in activity in the left anterior insula. However, this region was also associated with general task accuracy (which furthermore correlated directly with stopping efficacy), suggesting that it might actually reflect a more general mechanism of performance control that supports response inhibition in a relatively nonspecific way.

Download full-text


Available from: Lawrence Gregory Appelbaum, May 08, 2014
  • Source
    • "This is consistent with activity in extrastriate areas which is modulated by the prefrontal cortex. These results converge with fMRI-findings of enhanced inferior parietal activity in response to stop-and nogo-signals, especially if they are task-relevant (Boehler et al., 2010). The posterior negativity was slightly enhanced in failed compared to successful trials under both stop-and change-conditions, which was unexpected if assuming that it reflects orienting of attention towards the stop-signal. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Response inhibition is an essential control function necessary to adapt one's behavior. This key cognitive capacity is assumed to be dependent on the prefrontal cortex and basal ganglia. It is unresolved whether varying inhibitory demands engage different control mechanisms or whether a single motor inhibitory mechanism is involved in any situation. We addressed this question by comparing electrophysiological activity in conditions that require stopping a response to conditions that require switching to an alternate response. Analyses of electrophysiological data obtained from stop-signal tasks are complicated by overlapping stimulus-related activity that is distributed over frontal and parietal cortical recording sites. Here, we applied Laplacian transformation and independent component analysis (ICA) to overcome these difficulties. Participants were faster in switching compared to stopping a response, but we did not observe differences in neural activity between these conditions. Both stop- and change-trials Laplacian transformed ERPs revealed a comparable bilateral parieto-occipital negativity around 180ms and a frontocentral negativity around 220ms. ICA results suggested an inhibition-related frontocentral component which was characterized by a negativity around 200ms with a likely source in anterior cingulate cortex. The data provide support for the importance of posterior mediofrontal areas in inhibitory response control and are consistent with a common neural pathway underlying stopping and changing a motor response. The methodological approach proved useful to distinguish frontal and parietal sources despite similar timing and the ICA approach allowed assessment of single-trial data with respect to behavioral data. Copyright © 2015. Published by Elsevier B.V.
    International journal of psychophysiology: official journal of the International Organization of Psychophysiology 02/2015; 26. DOI:10.1016/j.ijpsycho.2015.01.012 · 2.65 Impact Factor
  • Source
    • "Despite clear evidence for right side dominance in stopping as indicated by the conjunction analyses, we also noted left IFC involvement specifically in stopping at more liberal thresholds, with preliminary evidence of reduced activation in the ADHD group. However, Left IFC involvement in stopping has been noted in meta-analyses and recent studies [Boehler et al., 2010; Swick et al., 2008, 2011], with reduced activation observed in adult ADHD patients [Cubillo et al., 2010] consistent with present findings. Despite group differences in the right IFC associated with stopping compared with shifting, activation in this area was noted in both groups separately. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Adult ADHD has been linked to impaired motor response inhibition and reduced associated activation in the right inferior frontal cortex (IFC). However, it is unclear whether abnormal inferior frontal activation in adult ADHD is specifically related to a response inhibition deficit or reflects a more general deficit in attentional processing. Using functional magnetic resonance imaging, we tested a group of 19 ADHD patients with no comorbidities and a group of 19 healthy control volunteers on a modified go/no-go task that has been shown previously to distinguish between cortical responses related to response inhibition and attentional shifting. Relative to the healthy controls, ADHD patients showed increased commission errors and reduced activation in inferior frontal cortex during response inhibition. Crucially, this reduced activation was observed when controlling for attentional processing, suggesting that hypoactivation in right IFC in ADHD is specifically related to impaired response inhibition. The results are consistent with the notion of a selective neurocognitive deficit in response inhibition in adult ADHD associated with abnormal functional activation in the prefrontal cortex, whilst ruling out likely group differences in attentional orienting, arousal and motivation. Hum Brain Mapp, 2014. © 2014 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
    Human Brain Mapping 10/2014; 35(10). DOI:10.1002/hbm.22539 · 6.92 Impact Factor
  • Source
    • "However, as these regions are activated by successful and unsuccessful inhibition to a varying extend and as patients might differ from control groups not only in inhibitory but also in error processing, conflating successful and unsuccessful inhibition trials will most likely bias the results. Third, inhibitory processing is present in unsuccessful inhibition trials, albeit in a less pronounced or weakened form (Boehler et al., 2010). Taken together, not dissociating successful and unsuccessful inhibition trials might distort group differences in brain activation patterns as a function of inhibitory processing. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Disorders such as borderline personality disorder (BPD) or attention-deficit/hyperactivity disorder (ADHD) are characterized by impulsive behaviors. Impulsivity as used in clinical terms is very broadly defined and entails different categories including personality traits as well as different cognitive functions such as emotion regulation or interference reso-lution and impulse control. Impulse control as an executive function, however, is neither cognitively nor neurobehaviorally a unitary function. Recent findings from behavioral and cognitive neuroscience studies suggest related but dissociable components of impulse control along functional domains like selective attention, response selection, motivational control, and behavioral inhibition. In addition, behavioral and neural dissociations are seen for proactive vs. reactive inhibitory motor control.The prefrontal cortex with its sub-regions is the central structure in executing these impulse control functions. Based on these con-cepts of impulse control, neurobehavioral findings of studies in BPD and ADHD were reviewed and systematically compared. Overall, patients with BPD exhibited prefrontal dysfunctions across impulse control components rather in orbitofrontal, dorsomedial, and dorsolateral prefrontal regions, whereas patients with ADHD displayed disturbed activity mainly in ventrolateral and medial prefrontal regions. Prefrontal dysfunctions, however, varied depending on the impulse control component and from disorder to disorder. This suggests a dissociation of impulse control related frontal dysfunctions in BPD and ADHD, although only few studies are hitherto available to assess frontal dysfunctions along differ-ent impulse control components in direct comparison of these disorders.Yet, these findings might serve as a hypothesis for the future systematic assessment of impulse control com-ponents to understand differences and commonalities of prefrontal cortex dysfunction in impulsive disorders.
    Frontiers in Human Neuroscience 09/2014; 8:698. DOI:10.3389/fnhum.2014.00698 · 2.90 Impact Factor
Show more