![]() ![]() Continuous performance monitoring is important for guiding behavior towards successful goal-attainment by detecting deficiencies and strategically adjusting responses when current performance is inadequate. ![]() These evaluative monitoring processes serve to adjust behavioral performance toward goal attainment based on the detection of performance errors (Ridderinkhof et al., 2004). Numerous functional magnetic resonance imaging (fMRI) studies (i.e., Carter et al., 1999, MacDonald et al., 2000) suggest that cognitive control comprises two broad component processes implemented in a closely interactive, yet dissociable frontal neural network: a regulative/strategic component supporting the maintenance of task goals, allocation of limited attentional resources, and the implementation of top-down control (MacDonald et al., 2000), and an anterior cingulate cortex (ACC)-mediated evaluative component that supports conflict processing and performance monitoring (i.e., Carter and van Veen, 2007, Kerns et al., 2004, van Veen and Carter, 2002, van Veen and Carter, 2006). Severity-related impairments in “cognitive control,” a set of higher-order executive processes supported by the prefrontal cortex and critical to executive function (Lorist et al., 2005, Miller, 2000, Miller and Cohen, 2001), are thought to underlie some aspects of enduring cognitive dysfunction after brain injury (Larson et al., 2006, Larson et al., 2007a, Larson et al., in press, Perlstein et al., 2004, Perlstein et al., 2006, Scheibel et al., 2007, Seignourel et al., 2005, Soeda et al., 2005), and current theories of neurobehavioral dysfunction in TBI have been based on observed impairments in cognitive control component processes (Anderson et al., 2002, Burgess and Robertson, 2002, Larson et al., 2006, Larson et al., 2007a, Levine et al., 2002, Perlstein et al., 2006). Physical and neurobehavioral impairments are common sequelae of traumatic brain injury (TBI Horn and Sherer, 1999), however, even in patients with good neurological recovery, persistent cognitive deficits are among the most pronounced and frequent complaints of TBI survivors (Cicerone et al., 2005, Lovell and Franzen, 1994). Implications for future research and potential limitations in conducting fMRI research in neurologically-impaired populations are discussed, as well as some potential benefits of employing multimodal imaging (e.g., fMRI and event-related potentials) of cognitive control processes in TBI. fMRI data revealed that, compared to controls, sTBI patients showed greater magnitude error-related activation in the anterior cingulate cortex (ACC) and an increase in the overall spatial extent of error-related activation across cortical and subcortical regions. Behaviorally, sTBI patients showed greater error-rate interference than neurologically-normal controls. fMRI data were analyzed using a random-effects whole-brain voxel-wise general linear model and planned linear contrasts. fMRI and behavioral data were acquired while 10 sTBI participants and 12 neurologically-healthy controls performed a task-switching cued-Stroop task. In the present study, we exploited the advantages of event-related functional magnetic resonance imaging (fMRI) to examine brain activity associated with error-related processing after severe traumatic brain injury (sTBI). Continuous monitoring of one's performance is invaluable for guiding behavior towards successful goal attainment by identifying deficits and strategically adjusting responses when performance is inadequate. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |