Personal space and aging in Japanese adults: The role of demographics and sensory function

• In Japanese people, aging expands personal space (PS) only in men. • Demographic variables significantly explained PS while the sensory decline did not. • Self-protection, one of the PS’s mechanisms, was not supported. • Inter-individual difference in discomfort tolerance was confirmed for each PS. Personal space is the area around an individual that, when intruded upon, causes discomfort related to self-protection. While aging tends to expand personal space owing to functional decline, our preliminary survey results suggest that Japanese individuals do not believe this applies to older Japanese adults. We further investigated the effect of age and sensory function, in addition to other confounding variables such as gender, on personal space, among Japanese adults by using two methods for validity: the standard stop-distance paradigm and the discomfort paradigm. Because the results for the stop-distance paradigm and discomfort paradigm did not correlate well, we utilized the results of the discomfort paradigm to predict participants’ feelings of discomfort with the distance as assessed by the stop-distance paradigm. Age-related expansion of personal space was observed only in men, which does not fully conform to the findings of previous studies or the proposed underlying mechanism of self-protection. Further, while sensory function did not significantly explain variability in personal space, demographic variables, such as gender, significantly affected personal space and were interpretable given the cultural characteristics and health-related factors of Japanese people, which are further discussed.