Evidence for Anterior Cingulate Cortex Involvement in Monitoring Preparatory Attentional Set

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The anterior cingulate cortex (ACC) participates in both performance optimization and evaluation, with dissociable contributions from dorsal (dACC) and rostral (rACC) regions. Deactivation in rACC and other default-mode regions is important for performance optimization, whereas increased rACC and dACC activation contributes to performance evaluation. Errors activate both rACC and dACC. We propose that this activation reflects differential errorrelated involvement of rACC and dACC during both performance optimization and evaluation, and that these two processes can be distinguished by the timing of their occurrence within a trial. We compared correct and error antisaccade trials. We expected errors to correlate with an early failure of rACC deactivation and increased activation of both rACC and dACC later in the trial. Eighteen healthy subjects performed a series of prosaccade and antisaccade trials during event-related functional MRI. We estimated the hemodynamic responses for error and correct antisaccades using a finite impulse-response model. We examined ACC activity by comparing error and correct antisaccades with a fixation baseline and error to correct antisaccades directly. Compared with correct antisaccades, errors were characterized by an early bilateral failure of deactivation of rACC and other default-mode regions. This difference was significant in rACC. Errors also were associated with increased activity in both rACC and dACC later in the trial. These results show that accurate performance involves deactivation of the rACC and other default mode regions and suggest that both rACC and dACC contribute to the evaluation of error responses.default-mode network ͉ performance evaluation ͉ task-induced deactivation ͉ inhibition ͉ cognition E lectrophysiological and neuroimaging studies consistently report anterior cingulate cortex (ACC) activity during error commission (1-5). The ACC, however, is a heterogeneous structure that can be parsed into dorsal (dACC) and rostral (rACC) regions based on cytoarchitecture, function, and connectivity (6-9). The dACC extends caudally from the genu of the corpus callosum to the vertical plane of the anterior commissure and connects with the lateral prefrontal cortex and hippocampus to regulate effortful cognitive operations. The rACC lies anterior and ventral to the genu of the corpus callosum and forms a circuit with the amygdala, insula, and ventral striatum to oversee emotional processing (for review, see ref. 10). Given these specializations, it is likely that the dACC and rACC make different contributions during error commission. In the present study, we examined activity in both these regions during different phases of error commission.Error-related activity in both rACC and dACC is thought to reflect their contributions to performance evaluation (2, 5, 11). The dACC is believed to be the primary generator of the error-related negativity (ERN) (5, 12), an event-related potential occurring 80-180 ms post-error (13), although a generator in the medial prefrontal cor...

Section: Discussionsupporting

confidence: 89%

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confidence: 99%

Rostral and dorsal anterior cingulate cortex make dissociable contributions during antisaccade error commission

Polli

Barton

Cain

et al. 2005

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163

“…The weak association requires a relatively greater amount of cognitive effort for the association to be available to consciousness. Another study manipulated task cues so that advance preparation of the upcoming task could be triggered on some trials (10). In this study, both ACC and lPFC activations were higher with an informative task cue than with a neutral cue.…”

mentioning

confidence: 85%

Anticipation of conflict monitoring in the anterior cingulate cortex and the prefrontal cortex

Sohn

Albert

Jung

et al. 2007

144

The anterior cingulate cortex (ACC) has been suggested as a monitoring center that is responsible for online detection of response conflicts. In this view, the conflict signal detected by the ACC is transmitted to other brain regions, such as the dorsal part of the lateral prefrontal cortex (lPFC), to increase the level of cognitive control. In this functional MRI (fMRI) study, we examined the conflict resolution that goes beyond online detection of response conflicts. Participants learned pseudoarithmetic problemsolving tasks that involve stimulus-response mapping rules with high or low conflicts. On half of the trials, participants had a preview of the upcoming operator that allowed advance preparation for the mapping rules. The preview significantly reduced the conflict effects on latency. During the preview, both the ACC and lPFC were activated in anticipation of conflict, and this anticipatory activation was highly predictive of the subsequent latency. These results suggest that the ACC and lPFC are responsible for both anticipatory preparation and online adjustment in response to conflicts. The results also confirm the roles of the lPFC and ACC in managing conflict during problem solving and extend these roles to include responding to anticipation of conflicts that may arise between incompatible stimulus-response mappings maintained in working memory during preparation.lateral prefrontal cortex ͉ preparation ͉ problem solving E ffective task execution requires a mixture of bottom-up and top-down control. Although it is preferable to stay focused on the task-relevant information, it is not efficient to constantly rely on executive mechanisms. Executive mechanisms take a substantial toll on working memory to maintain task-relevant information. Moreover, a strict top-down approach impedes flexible responses to unexpected, yet meaningful, events. In contrast, when stimulus-driven processing dominates, the course of action digresses constantly, interfering with goal-directed behavior.Cognitive neuroimaging and neuropsychology studies have consistently shown that the lateral prefrontal cortex (lPFC), especially its dorsal stream, and the anterior cingulate cortex (ACC) are critically active when participants are engaged in cognitively demanding tasks. Although there is a consensus that lPFC is responsible for executive functions, such as maintaining and manipulating task-relevant information, the role of the ACC in cognitive control, although generally accepted, is still controversial. Some theories have argued that the ACC detects conflicting response tendencies in the environment, and others have suggested that the ACC may respond to cognitive complexity more generally.The conflict-monitoring model (1) has proposed that the ACC monitors competing response tendencies elicited by stimuli. According to this model, the conflict signal detected by the ACC is transmitted to a high-level control mechanism such as the lPFC, thereby increasing the extent of conscious control (2). The response conflict may arise when th...

“…Within the context of TS, simple comparisons of switch vs. repeat conditions have revealed a frontoparietal network including VLPFC, in addition to supplementary motor area (SMA) and inferior͞superior parietal cortices (18)(19)(20)(21)(22)(23)(24)(25). § Importantly, the switch-related activation in VLPFC has been modulated in experiments that test both reconfiguration and interference theories of TS (20,26,27). We posit that these initial findings, although potentially contradictory, when considered in the context of the broader literature on left VLPFC function, motivate the hypothesis that VLPFC is engaged to overcome interference between competing mnemonic representations retrieved during TS.…”

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confidence: 99%

Computational and neurobiological mechanisms underlying cognitive flexibility

Badre

Wagner

2006

170

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The ability to switch between multiple tasks is central to flexible behavior. Although switching between tasks is readily accomplished, a well established consequence of task switching (TS) is behavioral slowing. The source of this switch cost and the contribution of cognitive control to its resolution remain highly controversial. Here, we tested whether proactive interference arising from memory places fundamental constraints on flexible performance, and whether prefrontal control processes contribute to overcoming these constraints. Event-related functional MRI indexed neural responses during TS. The contributions of cognitive control and interference were made theoretically explicit in a computational model of task performance. Model estimates of two levels of proactive interference, ''conceptual conflict'' and ''response conflict,'' produced distinct preparation-related profiles. Left ventrolateral prefrontal cortical activation paralleled model estimates of conceptual conflict, dissociating from that in left inferior parietal cortex, which paralleled model estimates of response conflict. These computationally informed neural measures specify retrieved conceptual representations as a source of conflict during TS and suggest that left ventrolateral prefrontal cortex resolves this conflict to facilitate flexible performance.cognitive control ͉ executive function ͉ memory ͉ prefrontal cortex ͉ task switching T he course of modern life is often interrupted by demands that do not await our disposition but must be addressed immediately. The ability to reconfigure our cognitive system to meet shifting task demands is evident and remarkable. A fundamental problem in the study of cognitive control is specification of the psychological and neural processes by which we achieve this flexibility and successfully switch tasks. Task switching (TS) is studied by comparing episodes in which subjects switch between two simple tasks to those in which they repeat the same task (1-5). In such comparisons, TS incurs slowing in response time (RT), termed a switch cost. As a window onto the mechanisms of flexible performance, considerable attention has focused on characterizing the source of the switch cost, although extant data have generated controversy rather than resolution (2, 4).Two classes of theory have framed the debate over TS costs. Reconfiguration theories posit time-consuming intentional control processes that initiate reconfiguration of the task set independent of the presentation of a target stimulus (6). From this perspective, the switch cost reflects the time consumed by these control processes, and their progress during a preparation interval yields preparation-related reductions in the switch cost. Alternatively, interference theories propose that switch costs are substantially or wholly attributable to conflict arising from memory due to the recent performance of a different task (2,7,8). From one such perspective, performance of a given task primes associations among available cues and task representations (2, ...