Smiling makes you look older, even when you wear a mask: the effect of face masks on age perception

Ganel and Goodale Cognitive Research: Principles and Implications https://doi.org/10.1186/s41235-022-00432-3 (2022) 7:84 ORIGINAL ARTICLE Cognitive Research: Principles and Implications Open Access Smiling makes you look older, even when you wear a mask: the effect of face masks on age perception Tzvi Ganel1* and Melvyn A. Goodale2 Abstract The widespread use of face masks in the era of the Covid-19 pandemic has promoted research on their effect on the perception and recognition of faces. There is growing evidence that masks hinder the recognition of identity and expression, as well as the interpretation of speech from facial cues. It is less clear whether and in what manner masks affect the perception of age from facial cues. Recent research has emphasized the role of the upper region of the face, a part not covered by a mask, in the evaluation of age. For example, smile-related wrinkles in the region of the eyes make smiling faces appear older than neutral faces of the same individuals (the aging effect of smiling, AES). In two experiments, we tested the effect of face masks on age evaluations of neutral and smiling faces in a range of different age groups from 20 to 80 years. The results showed that smiling faces were perceived as older than neutral faces even when individuals were wearing a face mask—and there was no effect of masks on bias in age evaluations. Additional analyses showed reduced accuracy in age evaluations for smiling compared to neutral faces and for masked compared to unmasked faces. The results converge on previous studies emphasizing the importance of the upper region of the face in evaluations of age. Keywords: Face perception, Masked faces, Age evaluations, Facial expression, Smiling Significance statement In this manuscript, we provide a comprehensive investigation of the effect of masks on different aspects of age evaluations. Within this context, we looked at the effect of masks on age evaluations of neutral and smiling faces. We found that wearing a face mask does not diminish the well-established effect of smiling on age perception: the fact that when people smile, they look older. In addition, we showed that contrary to previous suggestions, masks do not make people appear to be younger or older. The only difference in age evaluations between masked and unmasked faces was a moderate decrease in accuracy for age evaluations of masked faces. The findings confirm *Correspondence: 1 Psychology Department, Ben-Gurion University of the Negev, 8410500 Beer‑Sheva, Israel Full list of author information is available at the end of the article that the perception of age is driven largely by the upper part of the face and that the wrinkling of the eyes that occurs when people smile is responsible for the bias in age perception. These results provide timely insights on the effect of masks on face perception and on the processes that underlie the perception of facial age. Introduction Extracting accurate information about the age of an individual allows for more effective social interactions. It is not surprising, therefore, that among the different features that people can readily extract from a person’s face, age is considered primary (George & Hole, 1998). To evaluate the age of someone’s face effectively, observers must take into account a wide range of age cues, including the overall shape of the face, the person’s hairstyle and hair colour, as well as the prominence of wrinkles and skin pigmentation (Lai et al., 2013; Voelkle et al., © The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. Ganel and Goodale Cognitive Research: Principles and Implications (2022) 7:84 2012). Although these age cues allow humans to achieve impressive accuracy in evaluating age, performance is still imprecise, leaving a large space for errors and biases. One such bias, described in a series of recent studies conducted in our lab, is the aging effect of smiling or AES: the fact that when a person smiles, they are perceived as older than when they maintain a neutral expression (Ganel, 2015; Ganel & Goodale, 2018, 2021). This bias has been shown to be a consequence of the failure of the observer to discount temporary information from smiling-induced wrinkling in the upper part of the face and, in particular, in the region of the eyes (Ganel, 2015). The perception of smiling faces as older is unintuitive, going against the common belief that smiling makes people look younger, not older (Ganel & Goodale, 2018). Recently, the AES has been extended for own- and otherrace faces (Yoshimura et al., 2021), and for own-race faces of different age groups (Ganel & Goodale, 2021). In particular, the AES was found for male and female faces in young people and for male faces in middle-aged people. Perhaps not surprisingly, no AES was found for faces of old adults, probably because they already have many facial wrinkles and other facial cues that mark them as older (Ganel & Goodale, 2021). The widespread usage of face masks in the era of the COVID-19 pandemic has created an opportunity for timely research on the effect of masks on different aspects of face perception and recognition. So far, research has shown that wearing a face mask can lead to decreased or even abnormal performance in key aspects of face processing. Such aspects include the identification of unfamiliar and familiar faces (Carragher & Hancock, 2020; Freud et al., 2020; Noyes et al., 2021), speech perception (Magee et al., 2020; Truong & Weber, 2021; Truong et al., 2021), and the processing of facial emotions both in children and in adults (Carbon, 2020; Carbon & Serrano, 2021; Gori et al., 2021; Grundmann et al., 2021; Marini et al., 2021; Ruba & Pollak, 2020). It is less clear, however, whether and in which manner masks affect the perception of age from a person’s face. Given the key role of the upper face region, which is typically not covered by masks, in age perception, it might be expected that masks would not lead to directional biases in the evaluation of age. Yet, the scarce research in this domain has not yielded firm conclusions as to the possibility of directional effects of faces masks o (...truncated)