Effects Of Visual Adaptation On The Perception Of Face And Body Attractiveness

Physical attractiveness plays a central role in many aspects of society.Individuals with higher physical attractiveness are considered to have more socially expected personality traits,which leads them to obtain greater opportunities and benefits than those with low attractiveness in various fields.Although humans have formed a series of stable physiological and psychological mechanisms during the evolution process,the preferences of different individuals for faces and bodies have shown a certain degree of stability and consistency.But because the human visual system is highly adaptive,short-term visual experience also affects our assessment of face and body attractiveness,meaning that an individual’s perception of face and body attractiveness can also be shaped or altered.Prolonged exposure to a stimulus produces opposite perceptual biases to subsequently presented stimuli with the same property.This is called the visual adaptation aftereffect.This is because as external stimuli change,our visual system is constantly making adaptive adjustments to reflect the changes we experience.The norm-based two-pool adversarial model and the exampler-based multichannel encoding model can explain the perceptual bias phenomenon caused by this adaptation.Since most visual stimuli can induce visual adaptation aftereffects through adaptation paradigms,individuals who adapt to a highly attractive face tend to perceive subsequently presented faces as less attractive,and vice versa.Previously,perceptual adaptation was thought to depend on the physical similarity between the adaptor and the test stimulus.However,recent evidence for cross-class adaptive aftereffects of identity,gender and age suggests that high levels of cross-body perceptual aftereffects may occur when the features requiring adaptation are not present in the adaptive stimulus but are inferred automatically from the presentation of concept-related objects.This suggests that the generation of aftereffects also depends on the intrinsic association between the adaptive stimulus and the test stimulus,that is,the shared semantic attributes or associated features between them.Faces and bodies do not have similar shape information,but they share some common characteristics,so they may have some kind of intrinsic relationship on the attractiveness dimension.Study 1 mainly explored the adaptation aftereffects of face attractiveness and its neural mechanism.The experiment adopts the classic adaptation paradigm.After 4seconds of acclimation to the high or low attractiveness female faces,a test face was presented quickly(0.2ms)and the subjects were required to judge whether the test stimulus was attractive or not by pressing a button.The experimental results found a significant adaptation aftereffect of face attractiveness: after subjects were adapted to highly attractive faces,they tended to perceive the subsequent face as unattractive.Conversely,after adapting to low attractive faces,they tend to perceive subsequent face as attractive.The ERP results showed that the latency of N250 r and the amplitude of LPP were modulated by the degree of similarity between the adaptor and the test stimulus on the level of attractiveness.Specifically,when the attractiveness levels of the adaptive stimulus and the test stimulus are congruent,the latency of N250 r is prolonged and the amplitude of LPP is suppressed;while when the attractiveness levels of the two are in congruent,the latency of N250 r is shortened and the amplitude of LPP is enhanced.It indicated that the N250 r and the LPP were the neural correlates of the adaptation aftereffects of face attractiveness.Study 2 mainly explored whether face attractiveness adaptation had an impact on the perception of physical attractiveness.The paradigm used in this study was basically same as that used in study 1.The adaptation stimulus was completely the same as that used in study 1.and the test stimuli employed 8 body pictures manipulating body size to change attractiveness.The results showed that adaptation to high-or low-attractiveness faces did not affect participants’ perception of subsequent physical attractiveness.The EEG results also did not reveal the existence of face-to-body cross-category attractiveness adaptation aftereffects.This suggests that the adaptation aftereffect of attractiveness is more dependent on the shape similarity of the adaptor and the test stimulus,or that the body feature associated with face attractiveness may be more than body size.Based on the above results,we found that N250 r and LPP are sensitive to the adaptation of face attractiveness.However,the adaptation aftereffects of face attractiveness can cross bodies,suggesting that shape similarity between the adaptor and test stimulus had a greater impact on the adaptation aftereffects of attractiveness.