Feedback delay gradually affects amplitude and valence specificity of the feedback-related negativity (FRN)

Processing of performance-related feedback is an essential prerequisite for adaptive behavior. Even though in everyday life feedback is rarely immediate, to date very few studies have investigated whether the feedback-related negativity (FRN), a relative negativity in the ERP approximately 200 to 300 ms after feedback that is sensitive to feedback valence and predictability, is modulated by feedback timing, and findings are inconsistent. The present study investigated effects of gradually increasing feedback delays on feedback processing in the FRN time window. Subjects completed a probabilistic learning task in which feedback was provided after short, intermediate, or long delays. Difference wave-based analyses showed that amplitudes decreased linearly with increasing feedback delay. A distinct pattern was observed for the FRN as defined in the original waveforms, with FRN amplitudes being largest for long and smallest for short delays. This pattern of results is consistent with the notion that the neural systems underlying feedback processing vary depending on feedback timing. The gradually reduced difference wave signal might reflect a gradual shift away from processing in frontostriatal circuits toward medial temporal involvement. To what extent increased signal amplitudes for longer delays in the original waveforms are related to processing in certain brain structures will need to be determined in future studies.