Effects Of Oxytocin On The Recognition Of Natural Microexpressions

Oxytocin,also known as oxytocin,not only has clinical effects such as inducing labor and hemostasis after delivery,but also can effectively lower blood pressure,promote maternal love and promote prosocial behavior.Oxytocin has been shown to help individuals infer other people’s feelings and psychological states from subtle social cues and to facilitate recognition of facial expressions.At present,it is generally believed that expressions can be divided into two categories: macro expressions and micro expressions.A macro expression is a prominent and long lasting expression(1 to4 seconds)that provides rich information and is easy to recognize.Microexpressions,however,have a short duration(less than 0.5 seconds)and are difficult to detect.They are a suppressed expression of emotion and an effective clue for detecting lies.At present,researches on the effect of oxytocin on facial expression recognition are mainly limited to macroexpressions,and macroexpressions alone cannot fully reveal the role of oxytocin in facial emotional processing.Therefore,it is particularly important to study the effect of oxytocin on microexpression recognition.In the past,researchers have studied the effect of oxytocin on the recognition of microexpressions through standardized microexpressions.Although the presentation of standardized microexpressions is also dynamic,such movements are more like movements and lack of intermediate action information.However,in real situations,the trajectory of microexpressions is continuous and accompanied by certain body language.The effect of oxytocin on microexpression recognition cannot be fully understood by studying standardized microexpressions alone.In order to better understand the influence of oxytocin on microexpression recognition,natural microexpression materials will be selected in this study and the influence of oxytocin on natural microexpression recognition will be further investigated in combination with eye movement technology.In this study,two studies were conducted to investigate the effect of oxytocin on natural microexpression recognition.In study 1,we used a mixed experimental design to examine the effect of oxytocin on the recognition of six basic natural microexpressions(sadness,surprise,anger,disgust,fear,and joy).The results showed that under the control condition(i.e.,without microexpression recognition training),there were no significant differences in response time and recognition accuracy between the oxytocin group and the placebo group on the six basic natural microexpressions.Under the training condition,there were significant differences in the recognition accuracy of disgust and surprise microexpressions between the oxytocin group and the placebo group.The recognition accuracy of surprise and disgust microexpressions in the oxytocin group was lower than that in the placebo group.In order to further explore oxytocin is how to affect surprise and disgust natural micro expression recognition,on the basis of the study will be in a mixed experimental design is used to investigate oxytocin group of subjects with surprise and disgust natural micro expression recognition accuracy is reduced,whether because of oxytocin changed subjects in surprise and disgust the eye movement mechanism in the process of natural micro expression recognition.Considering that the two groups of natural microexpressions(fear and surprise,anger and disgust)have similar facial features and are easy to be confused in recognition,we retained four natural microexpression materials(disgust,surprise,fear and anger)in the second study.Try to be natural micro expression recognition on five interested area(eyebrow eye,nose,face area,frontal area,mouth area)of the four types of eye movement indices(for the first time to enter the length,number,percentage of fixation time,fixation point number regressive)eye movement analysis,the results showed that oxytocin group of subjects with placebo participants in identifying differences between natural micro expression to surprise and disgust.In terms of the first entry time of surprise and disgust and the number of return,the oxytocin group was longer than the placebo group in the eyebrow and eye region,and the oxytocin group was significantly more than the placebo group in the eyebrow and eye region.The results also showed that participants in the oxytocin group spent longer in the nasal region than those in the placebo group,and returned their eyes to the nasal region significantly more often than those in the oxytocin group.The results of studies 1 and 2 showed that oxytocin reduced participants’ accuracy in recognizing the two natural microexpressions of disgust and surprise,possibly because oxytocin inhibited the recognition of these two natural microexpressions.This inhibition may be due to the fact that oxytocin affected the eye movement process of the subjects’ first entry and return times during the recognition of these two natural microexpressions,thus leading to the shallow processing of these two natural microexpressions.These findings further reveal the effect of oxytocin on microexpression recognition and provide a theoretical basis for studying the mechanism of eye movement between oxytocin and microexpression recognition.