Two types of action error: electrophysiological evidence for separable inhibitory and sustained attention neural mechanisms producing error on Go/No-go tasks.

Abstract

Disentangling the component processes that contribute to human executive control is a key challenge for cognitive neuroscience. Here, we employ Event-Related Potentials to provide electrophysiological evidence that action errors during a Go/No-go task can result either from sustained attention failures, or from failures of response inhibition, and that these two processes are temporally and physiologically dissociable, even though the behavioural error ? a non-intended response ? is the same. Thirteen right-handed participants performed a version of a Go/No-go task in which stimuli were presented in a fixed and predictable order thus encouraging attentional drift and a second version in which an identical set of stimuli were presented in a random order thus placing greater emphasis on response inhibition. Electro-cortical markers associated with goal maintenance (late positivity, alpha synchronisation) distinguished correct and incorrect performance in the fixed condition while errors in the random condition were linked to a diminished N2/P3 inhibitory complex. In addition, the amplitude of the Error-Related Negativity did not differ between correct and incorrect responses in the fixed condition consistent with the view that errors in this condition do not arise from a failure to resolve response competition. Our data provide an electrophysiological dissociation of sustained attention and response inhibition.