Cognitive mechanisms of the face context effect: An event related potential study of the effects of emotional contexts on neutral face perception

Face context effect refers to the influence of the emotional context on facial expression perception. Numerous empirical studies have explored the mechanisms of the face context effect, but no consistent conclusions have been drawn. Hence, we investigated the cognitive mechanisms of the face context effect using recordings of event-related potentials. In Experiment 1, we adopted the context-target paradigm to explore the mechanisms of the effect of context with different emotional valences on the neutral face perception (emotional valence-based face context effect). In Experiment 2, we explored the mechanisms of the effect of context with different emotional types on the neutral face perception (specific emotion-based face context effect). The results of Experiment 1 indicated that the participants were biased toward contextual valence when recognizing the emotional valence of neutral faces, and that the neutral target faces under emotional contexts with different valences induced significant differences in the P1, N170, and LPP amplitudes. In Experiment 2, the results of Experiment 2 indicated that the participants were biased toward specific contextual emotions when recognizing the emotion type of neutral faces, and that the neutral target faces under contexts of different emotional types induced significant differences in the LPP amplitude, but not in the P1 or N170 amplitude. We concluded that the emotional valence-based face context effect occurred in the early processing stage, whereas the specific emotion-based face context effect occurred in the late processing stage.