Editorial: Studies of Face and Body

This special issue of Japanese Psychological Research, titled Studies of Face and Body, explores the intricate mechanisms and multifaceted aspects of face and body perception, cognition, and social significance. This issue is part of a project funded by the MEXT Grant-in-Aid for Scientific Research on Innovative Areas, titled Construction of Face−Body Studies in Transcultural Conditions. This research project initiative on face and body studies in Japan spanned from 2017 to 2022 and aims to heighten awareness about the unconscious expressions of faces and bodies and the cultural differences in these expressions.

Facial and bodily expressions serve as transparent mediums, revealing individual histories and enabling people to be understood by others. However, research has often been conducted on faces and bodies as separate entities. Recognizing the importance of integrating these two fields, our project aims to uncover the differences in facial and bodily expressions across diverse cultures and to explore the possibilities for developing cultural understanding through faces and bodies. By bringing unconscious facial and bodily expressions to conscious awareness, this field of study seeks to enhance the understanding of different cultures and the acceptance of diverse individuals. Multidisciplinary research methods, including psychological, anthropological, and philosophical perspectives, are used to elucidate cultural differences, aiming to clarify the commonalities and differences in facial and body expressions, considering both cultural and individual variations. Our project's goals align with the recent trend of developing integrated research on face and body perception, as evidenced by major international psychological conferences, such as the Vision Sciences Society (VSS), which included presentations on face and body perception in the same session in VSS 2024.

As a part of our project and to promote research on face and body studies, we feature this special issue. This special issue received 22 submissions, of which 12 were accepted for publication: eight focusing on face studies and four on body studies. We are grateful for the substantial number of submissions, which showcase a diverse range of topics.

Among the accepted papers, there are four notable review papers. Fort et al. (2024) explore the developmental trajectory of face processing and provide a comprehensive view of perceptual narrowing. Silvestri and Macchi Cassia (2024) examine how infants perceive trustworthiness in faces and the role of spatial frequency in this process. Tanaka (2024) offers a thorough overview of how body image develops in infants. Amita et al. (2024) review the neuronal mechanisms involved in face processing in primates.

In addition to these reviews, experimental studies provide fresh insights into various aspects of face and body perception. Chuang and Fujiwara (2024) address the unexplored cross-cultural variability of facial mimicry by analyzing video data from Japan, Spain, and Taiwan. The study finds significant differences in mimicry extent among the different cultures and examines the association between personality traits and mimicry. Yagi et al. (2024) measure observers' tendencies to approach infant faces using a manikin task, where participants are asked to either move closer to or farther away from displayed face images.  The participants showed a stronger inclination to approach infant faces compared to adult faces, suggesting that infant faces are more effective in eliciting approach behaviors. Fukuichi et al. (2024) identify helpful body-scan postures for people with ADHD tendencies, finding that supine postures made the body scan meditation easier to perform for individuals with hyperactivity/impulsivity tendencies. Yang et al. (2024) examine factors that distinguish real human motion from AI-generated movements, highlighting criteria such as kinematics, context, body mechanics, and principles of physical laws. Ikeda (2024) explores approach-avoidance responses to anger and fear as visualized through facial expressions and bodily postures, suggesting that both signals can elicit these responses. Nittono and Ohashi (2024) investigate whether the task of evaluating cuteness-versus-beauty affects smiling responses. The study shows that observing cuteness enhances smiling responses more than observing beauty. Shimizu et al. (2024) investigate the relationship between the intensity of emotional expressions in facial stimuli and the receivers' decoding accuracy for six basic emotions. The study found that higher intensity does not necessarily lead to higher decoding accuracy. Namba et al. (2024) examine how facial expressions of fun convey information and how this varies depending on social context. The results indicate that expressions of internal states are primary but vary in strength based on the presence of others.

This special issue serves as a comprehensive resource for researchers, offering a deeper understanding of the multifaceted nature of face and body processing. By bringing together diverse perspectives and cutting-edge research, we aim to foster further advancements in this vibrant field of psychological science. We hope that the articles presented in this issue will inspire young researchers, especially those new to the field of face and body studies, to delve more deeply into this fascinating area of research and contribute to its future development.