The Impact Of Expectation On The Emotion Susceptibility To Fearful Facial Expressions

Emotion is known to interact with cognition. Emotion modifies the efficiency and direction of cognition, while cognition regulates emotion and its strength. Nevertheless, as a special form of cognition, how clear expectation of incoming emotion events influences the human susceptibility to emotion events remains unclear. Particularly, fearful facial expression is socially and adaptively important, as the detection of fearful expression in other's face is indicative of potential threats in surroundings. Thus, using two Event-related potential experiments, the thesis investigated the impact of emotion expectation on the human susceptibility to fearful facial expressions.Using an emotion evaluation task, experiment 1 showed faster response times for expressions under expectation versus non-expectation. Moreover, the brain activation measured by VPP and 200-300ms amplitudes were similar for fearful and neutral expressions under expectation, while the brain response was enhanced for fearful than for neutral faces under non-expectation.Using a gender discrimination task where processing resources were distracted from emotion dimension of the stimuli. Experiment 2 replicated the results of Experiment 1 by revealing that:1) gender discrimination for fearful faces was impaired in non-expectation but not in expectation conditions, and 2) the emotion brain effects measured at VPP and 200-250ms intervals were decreased during expectation than during non-expectation conditions. Therefore, valid expectation for fearful faces decreased the human brain susceptibility to these faces. This effect is robust and reliable, characterized by the independence of experimental tasks and cognitive resources to some extent.