This review integrates findings from 40 years of event-related potential (ERP) studies using pictures that vary in valence (unpleasant to pleasant) and arousal (low to high) to elicit emotional processing. Affective stimulus factors primarily modulate ERP component amplitudes, with little change in peak latency observed. Arousal effects are consistently obtained and generally occur at longer latencies, while valence effects are inconsistent and reported at several latency ranges, including very early components. The review discusses the theoretical implications of affective ERP modulations, such as attention orientation for unpleasant pictures at early components (<300 ms) and enhanced stimulus processing for arousing pictures of assumed intrinsic motivational relevance, with task-induced differences contributing to emotional reactivity at later components (>300 ms). The review also addresses methodological issues, stimulus factors, task demands, and individual differences, highlighting the need for further research to clarify the complex dynamics of affective ERP processing.This review integrates findings from 40 years of event-related potential (ERP) studies using pictures that vary in valence (unpleasant to pleasant) and arousal (low to high) to elicit emotional processing. Affective stimulus factors primarily modulate ERP component amplitudes, with little change in peak latency observed. Arousal effects are consistently obtained and generally occur at longer latencies, while valence effects are inconsistent and reported at several latency ranges, including very early components. The review discusses the theoretical implications of affective ERP modulations, such as attention orientation for unpleasant pictures at early components (<300 ms) and enhanced stimulus processing for arousing pictures of assumed intrinsic motivational relevance, with task-induced differences contributing to emotional reactivity at later components (>300 ms). The review also addresses methodological issues, stimulus factors, task demands, and individual differences, highlighting the need for further research to clarify the complex dynamics of affective ERP processing.