The Influence Of Perceptual Experience On Face Holistic Processing:Perceptual Field And Eye-tracking Study

Humans are considered experts in face recognition,in fact,humans are just experts in identifying familiar faces.People are able to identify our family members and colleagues in situations where light,posture,expressions,etc.vary greatly.However,our ability to recognize unfamiliar faces is far less than familiar faces.Most people perform poorly when asked to judge the identity of a stranger or to match people to photos.There are great differences in the perception of familiar faces and unfamiliar faces.Understanding the underlying mechanisms of this difference helps us better understand the internal mechanisms of human face recognition.Using the size of the perceptual field in the newly proposed perceptual field hypothesis as the indicator of holistic processing,the aim of the present study was to investigate whether the individual experience of famous faces influence the face holistic processing,and what is the difference between the effect of inversion on the holistic processing of famous faces and non-famous faces.Besides,we explored the differences in eye movement patterns when perceiving famous faces and non-famous faces.Using a delayed matching task,in experiment 1,participants were presented with morphed faces of famous faces or non-famous faces,they were asked to choose the one that best matched to the morphed face between the two original faces: one face corresponded to the reference face's fixated part only(e.g.,one eye),the other corresponded to the unfixated area of the reference face.Results showed that the proportion of unfixated part selected by the participants(ie,the proportion of judgments based on the holistic processing),the famous faces were significantly higher than the non-famous faces;the familiarity of the participants with the famous faces was significantly positively correlated with the proportion of judgments based on the holistic processing for famous faces.It shows that the perceptual field of famous face is larger than non-famous faces,and as the subject is more familiar with the famous face,the level of holistic processing for famous faces also increases.On the basis of experiment 1,experiment 2 examined the influence of inversion on the perceptual fields of famous faces and non-famous faces.Results were as follows: the perceptual field of famous face is larger than non-famous face only when the face is upright;when the face is inverted,the difference disappears.When the face is upright,the familiarity of the participants with the famous faces was significantly positively correlated with the proportion of judgments based on the holistic processing for famous faces,same as experiment 1;however,the correlation between the two disappeared when the face is inverted.These results prove that the accumulation of individual experience will improve face holistic processing and inversion operation is more effective in reducing the perceptual field of famous faces.Experiment 3 uses eye movement techniques to explore the differences in eye movement patterns when perceiving famous faces and non-famous faces.Experiment 3 added eye movement control on the basis of experiment 2,behavioral results repeat the results of experiment 2.The mainly found in the eye movements were as follows:(1)There is an face inversion effect on the repeated part,for both number of fixations and fixation duration,and there is no face inversion effect on the unrepeated part;(2)On the repeated part of the face,the inversion effect of the famous face on the number of fixations is stronger than the inversion effect of the strange face;(3)For famous faces,the duration of a single gaze point when the subject observed the unfixated area of the face was significantly higher than that when observing the fixated area of the face.The results of eye movements show that the individual's long-term experience of famous faces and short-term experience of repeated faces both affect the eye movement patterns when perceiving faces.In summary,we found that:(1)Perceptual experience affects the perception of face by changing face holistic processing;(2)Inversion was more damaging to the holistic processing of faces with more experience;(3)The individual's eye movement pattern in perceiving a face is influenced by experience.