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


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.

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Available from: Lawrence Gregory Appelbaum, May 08, 2014
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    • "Robbins classify top-down inhibitory control as a higher order cognitive performance involving the complete or partial termination or overriding of a mental process (see also MacLeod, 2007). This process is largely carried out by frontal brain regions such as the dorso-lateral prefrontal cortex (dlPFC) (Delgado et al., 2008), the ventro-lateral prefrontal cortex and insula (vlPFC) (Boehler et al., 2010; Swick et al., 2008) as well as the anterior cingulate cortex (ACC) (Wascher et al., 2012; Rubia et al., 2001) which have been found to largely overlap in terms of cognitive and motor control (D'Esposito et al., 1999; Michael et al., 2006; Temel et al., 2005). In addition to age-related changes, frontal brain regions have also been highlighted as particularly vulnerable to the adverse effects of stress, which are thought to occur through an increased number of micro lesions produced by heightened hypertonic strain (Rabbitt, 2005). "
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    • "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. "
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