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To clarify the visual cues contributing to skin moisture and dryness, a research team from the Cognitive Neurotechnology Unit and Visual Perception & Cognition Laboratory of Toyohashi University of Technology, the Faculty of Design of Kyushu University, and the Central R&D Laboratory of Pias Corporation conducted several psychophysical experiments to investigate how image manipulation alters visual perceptions of skin moisture. The study demonstrated that emphasizing high-spatial-frequency components of skin lightness decreased the visual perception of moisture. These changes closely resembled physiological phenomena associated with skin dryness such as the appearance of white lines and emphasized pores, indicating that these are cues for perceiving skin dryness. The results of this study were published on December 17, 2024, in the Journal of the Optical Society of America A ( https://doi.org/10.1364/JOSAA.536898 ).
As the skin of a person's face undergoes physiological changes due to factors such as the amount of blood flow, it serves as a vital visual cue that influences the observer's impression and reflects the individual's health status. In addition, visual texture features like skin to the overall impression of skin. The visual system is thought to use cues such as skin lightness and color distribution to estimate skin glossiness contribute significantly glossiness. However, little is understood about the cues the visual system relies on to perceive skin moisture and dryness.
To address this gap, the research team conducted several psychophysical experiments to explore the types of visual factors influencing perceptions of skin moisture and dryness. For the experiment, images of human faces, cheeks and eyebrows were prepared, including versions with manipulated lightness. The participants were asked to rate these images on a scale from 1 ("Low") to 5 ("High") based on the three visual attributes of moisture, glossiness and attractiveness for the image stimuli that they were shown. The experiment was conducted in a dark room with controlled brightness levels to ensure that surrounding illumination did not influence the appearance of the skin.
The results confirmed a negative correlation between perceived skin moisture and image lightness variance. Skin images with increased high-spatial-frequency components for lightness (images adjusted to be brighter) were perceived as drier than unadjusted skin images. This effect is attributed to emphasized white lines and local contrast, which reduced the perception of moisture. These visual changes mirrored physiological phenomena associated with skin dryness such as the appearance of white lines and emphasized pores.
Yuya Hasegawa, the co-first author of this study and a doctoral student in the Department of Computer Science and Engineering explained, "The impression of a person's skin changes according to the individual and on a daily basis. What types of cues do observers use to make such judgments? This study was conceived based on the idea that, if we investigated the characteristics of images based on perceived moisture, we could discover visual cues for skin moisture and dryness."
The results revealed visual cues that contribute to the perception of decreased skin moisture and consequently skin dryness. However, as many unclear points regarding visual cues for increased skin moisture, we aim to investigate this further in future studies.
This research was supported by JSPS Grants-in-Aid for Scientific Research (Grant numbers: JP22K17987, JP20H05956 and JP20H04273) and conducted in collaboration with Pias Corporation.
Hasegawa, Y.†, Tamura, H.†*, Kanematsu, T., Yamada, Y., Ishiguro, Y., Nakauchi, S. & Minami, T. (2025). Visual cues for moisture perception of facial skin: A pilot study on the effects of enhancing high-spatial-frequency components of skin lightness to decrease perceived moisture levels in young Asian observes, Journal of the Optical Society of America A, 42(5), B23-B33, https://doi.org/10.1364/JOSAA.536898 .
†These authors share first authorship of this work. *Corresponding author.
