More Data, Please: Machine Learning to Advance the Multidisciplinary Science of Human Sociochemistry

Abstract

Communication constitutes the core of human life. A large portion of our everyday social interactions is non-verbal. Of the sensory modalities we use for non-verbal communication, olfaction (i.e., the sense of smell) is often considered the most enigmatic medium. Outside of our awareness, smells provide information about our identity, emotions, gender, mate compatibility, illness, and potentially more. Yet, body odors are astonishingly complex, with their composition being influenced by various factors. Is there a chemical basis of olfactory communication? Can we identify molecules predictive of psychological states and traits? We propose that answering these questions requires integrating two disciplines: psychology and chemistry. This new field, coined sociochemistry, faces new challenges emerging from the sheer amount of factors causing variability in chemical composition of body odorants on the one hand (e.g., diet, hygiene, skin bacteria, hormones, genes), and variability in psychological states and traits on the other (e.g., genes, culture, hormones, internal state, context). In past research, the reality of these high-dimensional data has been reduced in an attempt to isolate unidimensional factors in small, homogenous samples under tightly controlled settings. Here, we propose big data approaches to establish novel links between chemical and psychological data on a large scale from heterogeneous samples in ecologically valid settings. This approach would increase our grip on the way chemical signals non-verbally and subconsciously affect our social lives across contexts.

Smells in Sustainable Environments: The Scented Silk Road to Spending

“…Although we cannot rule out effects of increased mood by ambient scents like fresh linen because the absence of evidence does not mean the evidence of absence, it does seem the present findings are best intelligible from situated cognition theory (cf. de Groot et al, 2020b ). From this theory (e.g., Barsalou, 2016 ), scents are expected to fuel goal-directed behavior like buying clothing if the information a scent “communicates” (e.g., cleanliness) matches a person's criteria for buying second-hand clothing (e.g., needs to “feel” new, needs to be hygienic).…”

“…To conclude, higher external validity was traded off for potentially lower internal validity, or at least less experimental control. Yet, building on the numerous lab studies that have highlighted excellent human smell skills under sterile conditions (reviewed in e.g., McGann, 2017 ; de Groot et al, 2020b ), examining the effects of odors in natural settings seems inevitable to discover how important smells are to our everyday lives. Admittedly, even though the effect of fresh linen scent on spending behavior was strong, the sample was small.…”

Online Communication and Body Language

“…A new multidisciplinary discipline involving psychology and chemistry (sociochemistry) is studying the chemical basis of olfactory communication emphasizing the role of psychological states and traits in modulating body odorant composition (de Groot et al, 2020 ). Interestingly, data from patients with no or reduced olfactory capabilities show that the loss of smell severely affects the richness of social relationships over the lifespan from the early developmental stages to the old age (Boesveldt et al, 2017 ).…”

No effect of the smell of hexanal on trust in human-robot interaction

“…The impact of our sense of smell is often being underestimated, although over the last years research has uncovered that humans have a remarkably acute and perceptive sense of smell [14,15,16]. Humans are able to convey messages of gender, disease, personality, and emotions via their body odour, that other individuals can (subconsciously) perceive and act upon [e.g., 12,17,18,19]. Chemical signals are part of the broad array of channels that humans use to communicate socially, and our sense of smell may be one of the factors that can shift the balance of trust in cases where the collaboration is new or ambiguous.…”