Hyperactivity within an extensive cortical distribution associated with excessive sensitivity in error processing in unmedicated depression: A combined event-related potential and sLORETA study

• Both ERP and sLORETA were used to study the abnormal error processing in depression.
• Enhanced Ne amplitude indexed increased response monitoring during automatic error detection.
• Ne current density showed excessive hyperactivity over ACC, MFC, IPL and STG.
• The results may explain the excessive sensitivity in error processing in depression.

Individuals with depression are excessively sensitive to negative feedback and therefore overly cautious. To explore the neural mechanisms of response monitoring which contributed to their impaired behavioral adjustment, we recruited 22 individuals with depressive disorder and 24 healthy controls. Component analysis of the error-related negativity (ERN) and correct-related negativity (CRN), and sLORETA analysis of the ERN and CRN were combined. The comparable error rate and longer reaction time (RT) in individuals with depression as compared to healthy controls suggested a trade-off between accuracy and speed. The amplitude of the ERN and CRN was significantly enhanced in depression. Further sLORETA localizations of the ERN and CRN showed a significantly stronger current density with an extensive distribution in the anterior cingulate cortex (ACC), medial frontal cortex (MFC), inferior parietal lobule (IPL) and superior temporal gyrus (STG) in individuals with depression than in healthy controls. Increased activities in the ACC and MFC indexed increased response monitoring during automatic error detection, while hyperactivity over IPL and STG might indicate high uncertainness after error responses in depression. The hyperactivity within an extensive cortical distribution might be the neural basis of the excessive sensitivity to errors and the conservative accuracy/speed strategy in depression.