The Effect Of Unconscious Emotional Stimuli To Spatial Attnetion: ERP And FMRI Study

Visual selective attention includes endogenous and exogenous attention. Subjects can have an effective processing according the demands of tasks or attraction of characteristics of stimuli, so that make an adaptive response. Emotional studies said that processing of emotional stimuli is rapid and automatic, emotional stimuli can attract attention effectively and induce different influence to cognition. Do unconscious emotional stimuli also can cause the same effect? The current paper draw lessons from the last studies of emotional and spatial attention, adopt emotional facial pictures of different size and valence as the target and standard stimuli, acquired EEG data of fourteen right-handed healthy young adults and f-MRI data of eighteen normal subjects synchronously, to study the effect of unconscious emotion to spatial attention.The result of the positive and negative affective scale suggests the emotional state of subjects have no obvious fluctuation and in the normal range. The score of picture valances indicates participants can distinguish different emotional images.The behavioral results of EEG experiment suggest that the hit rate to target stimuli have a significant difference, especially in the condition of the right view. The result supports emotional stimuli can attract attention automatically. Unconscious perception to emotional pictures enhanced cognitive load of subjects. What is more, emotional processing has a right hemisphere’ advantage. The hit rate of f-MRI experiment suggests the same trend, but do not reach significance. The extension of response time provides enough time to respond, so that the effect of emotional pictures reduced corresponding.Results from EEG verify the effect of spatial attention, and confirmed unconscious emotional stimuli can also cause effect of attention. The result of emotional differences shows the different valence of emotional stimuli can cause different effect because of each physiological and biological importance meaning. The fear stimuli induce more attentional bias than happy stimuli, and leads to larger amplitude. The interaction of emotion and attention indicate unconscious emotional pictures based on different task status and goals, disturbing behavior in attentional state and contribute behavior in unattentional state.The fMRI result only compared different emotional state. The main areas related to spatial attention and some comprehensive functional areas such as cingulum and parahippocampal gyrus are activated, this may attribute to the factor of emotion and need further study.The above results verify the brain’s right hemisphere advantage of emotion processing, and indicate the emotional influence to spatial attention. Unconscious emotion can cause different effect to attention according to task status and goals. Results support automation of emotional processing, that is emotional processing is automatic independent of attention and conscious.