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Sander Nieuwenhuis

Publications and source records attributed to Sander Nieuwenhuis.

5 recordsLinked to original sources
PubMed2003

Errors are foreshadowed in brain potentials associated with action monitoring in cingulate cortex in humans.

Previous studies have reported electrophysiological brain activity that is modulated when subjects commit errors in speeded reaction time tasks. This activity is thought to index an action monitoring system in anterior cingulate cortex that signals the need for performance adjustments to minimize the risk of future errors. Consistent with this view, we report here that performance errors are foreshadowed in a modulation of this brain activity on the immediately preceding trial. We propose that this modulation reflects fluctuations in the efficiency of the action monitoring system, which may occasionally compromise subsequent performance and thus comprise a prelude to performance errors.

Adolescent↗
PubMed2003

Electrophysiological correlates of anterior cingulate function in a go/no-go task: effects of response conflict and trial type frequency.

Neuroimaging and computational modeling studies have led to the suggestion that response conflict monitoring by the anterior cingulate cortex plays a key role in cognitive control. For example, response conflict is high when a response must be withheld (no-go) in contexts in which there is a prepotent tendency to make an overt (go) response. An event-related brain potential (ERP) component, the N2, is more pronounced on no-go than on go trials and was previously thought to reflect the need to inhibit the go response. However, the N2 may instead reflect the high degree of response conflict on no-go trials. If so, an N2 should also be apparent when subjects make a go response in conditions in which no-go events are more common. To test this hypothesis, we collected high-density ERP data from subjects performing a go/no-go task, in which the relative frequency of go versus no-go stimuli was varied. Consistent with our hypothesis, an N2 was apparent on both go and no-go trials and showed the properties expected of an ERP measure of conflict detection on correct trials: (1) It was enhanced for low-frequency stimuli, irrespective of whether these stimuli were associated with generating or suppressing a response, and (2) it was localized to the anterior cingulate cortex. This suggests that previous conceptions of the no-go N2 as indexing response inhibition may be in need of revision. Instead, the results are consistent with the view that the N2 in go/no-go tasks reflects conflict arising from competition between the execution and the inhibition of a single response.

Adolescent↗
PubMed2002

Residual costs in task switching: testing the failure-to-engage hypothesis.

Reaction time is typically longer on trials on which the task changes. This switch cost is reduced by the opportunity to prepare for the change before the stimulus onset, but there remains a residual cost that resists reduction by further opportunity for preparation. De Jong (2000) proposed a model for evaluating the contribution to the residual cost of (1) failure to achieve endogenous task-set reconfiguration on a proportion of trials, and (2) limitations to the completeness of reconfiguration attainable by endogenous means. We report good fits of the model to the data from one previous and one new task-switching experiment, suggesting that the residual switch cost may indeed be attributable to a probabilistic failure to complete advance preparation. But strong incentives for preparation only marginally increased the estimated preparation probability, suggesting some intrinsic limitation to the ability to achieve endogenous preparation for a task switch on every trial.

Female↗
PubMed2002

A computational account of altered error processing in older age: dopamine and the error-related negativity.

When participants commit errors or receive feedback signaling that they have made an error, a negative brain potential is elicited. According to Holroyd and Coles's (in press) neurocomputational model of error processing, this error-related negativity (ERN) is elicited when the brain first detects that the consequences of an action are worse than expected. To study age-related changes in error processing, we obtained performance and ERN measures of younger and high-functioning older adults. Experiment 1 demonstrated reduced ERN amplitudes in older adults in the context of otherwise intact brain potentials. This result could not be attributed to uncertainty about the required response in older adults. Experiment 2 revealed impaired performance and reduced response- and feedback-related ERNs of older adults in a probabilistic learning task. These age changes could be simulated by manipulation of a single parameter of the neurocomputational model, this manipulation corresponding to weakened phasic activity of the mesencephalic dopamine system.

Adolescent↗