Title: Facial Preference, Gaze/Pupil, and Interpersonal Synchrony – How are They Related?
Author: Shinsuke Shimojo
Affiliation: California Institute of Technology, USA.
My talk will cross over different domains of research, which have been studied independently – preference/attractiveness of faces, gaze/pupil dynamics, and interpersonal behavioral/neural synchrony. First, preference or attractiveness decision making has been studied with a fixed (either static or dynamic) facial stimuli (Kim et al, 2007; Park et al., 2010). Second, gaze/pupil responses with regard to preference/attractiveness have been studied again with typically fixed facial stimuli (Shimojo et al. 2003; Liao et al., APCV 2015). This line of research emphasizes dynamic changes of gaze/pupil, yet remains mostly in the framework of stimulus-observer one-way relationship. Third, however, live, two-way interpersonal interactions were studied with interpersonal bodily/neural synchronizations as somatic, implicit bases of social interaction (Yun, et al., 2012). These three domains are closely related and progressively coming closer to the real-world natural social communication. I will try to provide research seeds across them; for example, what would happen if we use dynamic pupil change stimulus (though prefixed) with measurement of the observer’s dynamic pupil response, or if we measure pupil responses of two people actually interacting with each other? This will hopefully connect to the other talks in this symposium.
Title: Dynamics of Attractiveness Judgments
Author: Katsumi Watanabe
Affiliation: Waseda University/ University of Tokyo, Japan.
While attractiveness judgments can be done within a short period of time, it does not mean the attractiveness judgment is a simple, one-shot process. In this talk, I will present studies that examine the dynamic aspect of attractiveness judgment. One study concerns judgments of facial attractiveness as a combination of facial parts information over time and investigated how attractiveness judgment of each part of a face (i.e., eye, nose, mouth) would contribute to and be integrated into the attractiveness of the whole face. The results showed the eyes made a consistently high contribution to whole-face attractiveness, even with an observation duration of 20 ms, whereas the contribution of other facial parts increased as the observation duration grew longer. The other study examined the sequential dependence of attractiveness judgments. Responses in a current trial are biased by the stimulus and response in the preceding trial. We found that attractiveness judgment is also biased toward the preceding judgment, and hence the sequential effect can be extended into the domain of subjective decision making. These studies highlight the dynamic aspect of attractiveness judgments.
Title: There is No Hidden Beauty: Unconscious Processing of Facial Attractiveness
Authors: Shao-Min (Sean) Hung1, Chih-Hsuan Nieh2, & Po-Jang (Brown) Hsieh1
Affiliation: 1Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore./ 2Department of Psychology, National University of Singapore
Being appraised as attractive or not plays a pivotal role in one's life, influencing how one is judged, how easily one can be hired after an interview, and even how well an infant could capture his/her mother's attention. However, it remains elusive whether facial attractiveness can be extracted even in the complete absence of visual awareness. Here we showed unconscious processing of facial attractiveness with three approaches. In Experiment 1, the time taken for faces to enter consciousness under interocular suppression was measured. The results showed that attractive faces broke through suppression and reached consciousness earlier. In Experiment 2, we further showed that attractive faces had lower visibility thresholds under suppression, again suggesting that facial attractiveness could be processed more easily to reach consciousness. Crucially, in Experiment 3, an attractive face, albeit suppressed and invisible, could orient one's attention, resulting in a decrease of accuracy on a subsequent orientation judgment task. This effect disappeared with inverted faces, suggesting that the attentional effect was not driven by local features. Taken together, for the first time, we show that facial attractiveness can be processed in the complete absence of consciousness, and an unconscious attractive face is still capable of directing our attention.
Title: How does Pupillary Response Contribute to Interpersonal Preference Evaluation?
Authors: Hsin-I Liao1, Ying-Chun Chen2,3, Makio Kashino1, Shinsuke Shimojo2
Affiliation: 1NTT Communication Science Laboratories, Japan./ 2Divison of Biology, California Institute of Technology, USA./ 3Department of Industrial and Commercial Design, National Taiwan University of Science and Technology, Taiwan.
Our previous series of studies demonstrated that people’s pupils constrict, but not dilate, when seeing attractive faces (Liao et al., APCV 2015; TPA 2016). The result refutes the conventional belief of the positive interpersonal loop between pupil dilation and attractiveness in that a face with dilated pupil was looked more attractive and the pupil of the observer dilated when being attracted (e.g., Hess, 1965). In the current study, we examine the issue by using line-drawing faces with their pupil size manipulated. Participants judged the attractiveness of the faces with different pupil size while an eye-tracker camera recorded the participants’ own pupillary responses. The pupillary response results replicated our previous finding showing that participants’ pupils constricted stronger when they gave a higher score for the attractiveness judgment. Most importantly, contradictory to Hess’ finding, the behavior result indicated that the line-drawing faces with smaller pupil size appear more attractive. The overall results suggest that there is still positive interpersonal loop between the observer and the actor, but the loop is in the direction of pupil constriction, instead of dilation.
Title: Decoding preference decision making from footsteps and eyes
Authors: Makio Kashino
Affiliations: NTT Communication Science Laboratories / Tokyo Institute of Technology / JST CREST
Growing evidence shows that human behavior, decision making, emotion and communication depend critically on implicit brain functions, that is, automatic, involuntary neural processes even the person herself/himself is not aware of. We have been developing diverse methods to decode implicit brain functions from various data measured from body surface, e.g., involuntary body movements, eye dynamics, autonomic nerve activities, and hormone secretion. Here I introduce two topics: interpersonal body synchronization and eye dynamics. First, we developed a computational method to quantify the degree of body synchronization among multiple people, and demonstrated that the unconscious synchronization of footsteps between two people who met for the first time and were walking side-by-side for several minutes enhances positive impressions with each other. Interpersonal impression is, in an aspect, a dynamic phenomenon that emerges through the interaction mediated by bodies. Second, we developed a computational model of eye dynamics based on diverse features, including natural frequency and damping factor of microsaccades, and dilation and constriction of pupils. The model predicts observers’ preference for faces and music. Decoding information obtained from body surface, instead of the brain, provides practical and essential methods to uncover implicit brain functions underlying cognition and to develop user-friendly man-machine interfaces