Are humans constantly but subconsciously smelling themselves?. (8th June 2020)

• Record Type: Journal Article
• Authors: Perl, Ofer; Mishor, Eva; Ravia, Aharon; Ravreby, Inbal; Sobel, Noam
• Is Part Of: Philosophical transactions. Volume 375:Number 1800(2020)
• Publication Date: 2020-06-08
• Subjects: body-odour -- face-touching -- self-sampling -- self-sniffing -- social chemosignalling; Biology -- Periodicals; Science -- Periodicals; 570
• DOI: 10.1098/rstb.2019.0372
• Languages: English
• ISSNs: 0962-8436

Abstract

Abstract : All primates, including humans, engage in self-face-touching at very high frequency. The functional purpose or antecedents of this behaviour remain unclear. In this hybrid review, we put forth the hypothesis that self-face-touching subserves self-smelling. We first review data implying that humans touch their faces at very high frequency. We then detail evidence from the one study that implicated an olfactory origin for this behaviour: This evidence consists of significantly increased nasal inhalation concurrent with self-face-touching, and predictable increases or decreases in self-face-touching as a function of subliminal odourant tainting. Although we speculate that self-smelling through self-face-touching is largely an unconscious act, we note that in addition, humans also consciously smell themselves at high frequency. To verify this added statement, we administered an online self-report questionnaire. Upon being asked, approximately 94% of approximately 400 respondents acknowledged engaging in smelling themselves. Paradoxically, we observe that although this very prevalent behaviour of self-smelling is of concern to individuals, especially to parents of children overtly exhibiting self-smelling, the behaviour has nearly no traction in the medical or psychological literature. We suggest psychological and cultural explanations for this paradox, and end in suggesting that human self-smelling become a formal topic of investigation in the study of human social olfaction. This article is part of the Theo Murphy meeting issue 'Olfactory communication in humans'.