The Effect Of Context On The Processing Of Surprised Faces

Facial expressions play a critical role in the social communication as they express abundant information about individuals' emotions and social intentions.However,facial expressions are often perceived in specific contexts in our daily life.If we want to understand and recognize the facial expressions of others accurately,it is necessary to combine emotional faces with contextual information.Facial expression of surprise is a typical example.Specifically,people usually label surprised faces that presented in positive context as more pleasant,while surprised faces in negative contexts are rated more negative.What is worth reflecting on is how contextual information influences the perception of surprised faces.What is the neural mechanisms that underlie the context effect? Based on this background,the present study intend to explore the effects of context on the processing of surprised faces with a high time-resolution EPR technique.The aim of experiment 1 was to investigate the impact of emotional context on the processing of surprised faces.Happy,neutral,and fearful expressions projected in the eye regions were presented to serve as contextual information.Participants were asked to judge the valence of surprised face that had been preceded by a picture of an eye region.Behavioral results showed that the affective rating of surprised faces were context-dependent.ERP results showed that the amplitude of P1 was enhanced by preceding neutral eyes compared with fearful and happy eyes.N170 amplitudes in neutral and fearful eye contexts were significantly larger when compared with the happy context.The LPP component indicated enhanced brain activity in response to surprised faces preceded by happy and fearful eyes compared with neutral eyes.On the basis of experiment 1,the experiment 2 increased the complexity of the situational clues and aimed to investigate the effect of contextual sentences that including affective valence(positive,neutral,negative)and self-reference(self-related,other-related)cues on the perception of surprised faces.Participants viewed surprised faces preceded by positive,neutral,and negative sentences that addressed directly to the participants or others.Behavioral results showed that surprised faces in a self-relevant positive context were rated as more positive as compared to faces in other-relevant context,surprised faces in a self-relevant negative context were rated as more negative,whereas faces in other-relevant neutral context were rated as more positive as compared to faces in self-relevant context.ERP results showed that surprised faces in neutral context elicited enhanced P1 amplitude when compared with fearful context.N170 for faces in negative context compared to that in neutral and happy contexts were larger.An interactive effect of affective valence and self-reference occurred on the EPN component,with self-related neutral context information leading to more significant EPN than other-related neutral context,whereas other-related negative context leading to more pronounced EPN than self-related negative context.A modulation of self-reference appeared on the LPP,with enhanced LPP response to surprised faces in self-related context.Taken together,the following conclusions were obtained:1.The perception of surprised faces was context-dependent,in particular,affective context modulated the valence interpretation of surprised faces.2.Complex context that including affective and self-reference cues could impact the perception of surprised faces in an interactive pattern.3.The influence of context on the processing of surprised faces was a successive process(P1,N170,EPN,LPP),and the top-down strategic process had a modulation effect.