Can the negative deflections found with EEG on frontocentral electrodes be explained by one underlying process?
Summary
Several negative deflections have been found with EEG on frontocentral electrodes. Source localization and fMRI study have pointed all of these negativities in the vicinity of the anterior cingulate cortex (ACC). The function of the ACC has been a subject to studies for over several decades and the large similarities between the negative deflections suggest that they may be caused by one single process. Three major theories are discussed in relation with these negative deflections; the conflict monitoring theory, reinforcement learning theory and the error-likelihood model. All seem to lack the ability to reconcile all negative deflections with the model. An addition of the reinforcement learning theory was able to do that. In this model the ACC is selecting an appropiate action depending on stimulus-response and response-reward mappings. A reinforcement signal is adjusting these mappings, when an outcome is different from the expected outcome.