Neural Mechanisms Of Morphed Emotional Face Processing Using Magnetic Resonance Imaging Technique

Social interaction relies heavily on the processing and interpretation of non-verbal cues,the most important of which is facial emotion.Emotional face processing is not only a rapid,unconscious and highly specialized perceptual process,but also plays a crucial role in communication and social interaction.The ability to recognize emotional faces and the diversity of information it may convey is a key prerequisite for social functioning.Moreover,in everyday social interactions,individuals often encounter subtle(morphed)rather than completely intense or obvious emotional faces.Therefore,this study explores the neural mechanism of morphed emotional face processing from the dimensions of emotional intensity and gender.In this study,the task-state f MRI data of 88 healthy college students(44 males)were included in the analysis.During the MRI scan,they passively viewed randomly appeared neutral-happy,neutral-sad and sad-happy morphed emotional face pictures.The levels of anxiety and depression were assessed by the State-Trait Anxiety Inventory(STAI)and the Beck Depression Inventory-II(BDI-II),respectively.The results of the emotional intensity dimension showed that the right inferior frontal gyrus and left insula were significantly activated with the increase of happiness intensity during the processing of neutral-happy morphed emotional face;the right hippocampus and left insula were significantly activated with the increase of sadness intensity during the processing of neutral-sad morphed emotional face;the right fusiform gyrus and bilateral inferior frontal gyrus were significantly activated with the increase of happiness intensity during the processing of sad-happy morphed emotional face.In addition,activation of the right fusiform gyrus was significantly associated with higher levels of depression as sadness intensity increased during neutral-sad morphed emotional face processing.The results of the gender dimension showed that in the processing of sad-happy morphed emotional face,the activation of the left posterior cingulate cortex in the processing of the ambiguous faces(sad 65%-happy 35% + sad 35%-happy 65%)was significantly higher in the female than in the male compared with the anchor faces(100%sad+100% happy).Functional connectivity analysis showed that there were significant functional connectivity between the left posterior cingulate cortex and the right middle frontal gyrus,and the functional connectivity were stronger in males than in females.Correlation analysis showed that the BDI questionnaire had a significant negative correlation with the parameter estimates of male functional connectivity,but had no significant correlation with the parameter estimates of female functional connectivity.Further examining the difference between male and female correlation values,it is found that there is a significant difference between male and female.Moderating analysis showed that the interaction between the functional connectivity of the left posterior cingulate cortex and the right middle frontal gyrus and SAI or TAI scores significantly predicted depression levels.The above results deepen the understanding of morphed emotional face processing,enrich the research content of the neural mechanism of morphed emotional face processing,enhance the understanding of brain science theory,and provide theoretical basis for the treatment and intervention of mental disorders.