Abstract: The concept of error processing plays a central role in theories of cognitive control and performance monitoring. Effective behavior requires flexible and continuous performance monitoring. Identification and correction of differences between an intended an executed response (i.e., an error) are the main contents of the error processing. The research of the error-processing focused on the anterior cingulate cortex and the error-related negativity (ERN), a component of the event-related brain potential elicited when human participants commit errors or receives feedback indicating that they just made an erroneous response. There are four theories that account for the functional significance of ERN and ACC, such as error detection theory, reinforcement learning theory, conflict monitor theory, expectancy-deviation hypothesis. Despite in-depth insights provided by previous studies into our understanding of error processing, there are still some important questions to be answered, which might be the direction of future studies

Key words: error processing, neural mechanisms, anterior cingulate cortex, error-related negativity (ERN), feedback-related negativity (FRN)