Electrophysiological correlates of performance monitoring and error detection in response to augmented feedback

The ability to monitor performance and detect errors is essential for intelligent behaviour. Motor behaviourists have long been interested in how information about the performance of motor skills is used to facilitate learning. Recently, cognitive neuroscientists have also been interested in studying performance monitoring, particularly after the discovery of an event-related potential (ERP) component linked to error processing. This ERP component, aptly termed the error-related negativity (ERN), is observed in response to physical errors and also upon presentation of augmented feedback indicating performance errors or monetary losses. The neural generator of the ERN is thought to be located in the anterior cingulate cortex (ACC), a structure situated in the medial frontal wall of the human frontal lobe. ERN studies along with functional imaging experiments have suggested that ACC acts as part of an error detection system. In this thesis I challenge the notion that ACC activity, as measured by feedback ERN (f-ERN), is in fact related to errors. Experiment 1 measured participants' expectation of feedback by asking them to estimate their performance on each trial of an anticipation-timing task. The results show that f-ERN is elicited by feedback indicating both correct performance and errors, so long as expected feedback does not match the actual feedback. Experiment 2 replicated the results of Experiment 1 without asking participants to estimate their performance. This was accomplished by presenting false correct feedback in situations in which participants made errors. Taken together, the results of Experiments 1 and 2 suggest that ACC might not be selectively activated by errors, and that f-ERN might not be elicited exclusively by feedback indicating performance errors and monetary losses. I propose that f-ERN is the outcome of a more general system that searches the environment for violations of expectancy.