Strategic Design for “Smellscapes”: Do Smells Get Into Our Decisions?

Most design interventions manipulate the environment to convey sensory information to the public. However, aside from cosmetic industry, research on the olfactory modality has been broadly overlooked. Being one of the most ancient senses, smell provides motivational guidance within the environment, and some evidence has pointed to multisensory influences of smell. Thus, if the olfactory experience could surpass its mere perception and extend to our decisions, it would become a critical topic for design R&D. We assessed the influence of environmental smells on the performance of two distinct decision tasks, namely, a parallel response selection / conflict monitoring task (see Beste et al. 2013) and a cocoa taste-discrimination task, respectively employing an orthonasal (experiment 1) and a retronasal (experiment 2) smell exposure. Three identical laboratory rooms were used in both experiments to expose the participants to control, pleasant (apple fragrance scented room), and unpleasant (faecal / putrid room) smells in a counterbalanced within-subject design. Although participants’ response times were equivalent between conditions in experiment 1, the unpleasant room was associated with a decreased (albeit non-significant) number of errors. Remarkably, experiment 2 revealed that the unpleasant smell condition produced significantly more accurate judgments about the cocoa content of the trials than those obtained under pleasant (p< 0.01) and control (p< 0.05) conditions. Our findings are discussed considering the salience of smells (i.e., motivational value), and task demands (i.e., exposure length and type of cognitive processes engaged). Those factors likely combine to determine the resources (e.g., attention) allocated at each task and consequently, the degree of interference that smells could have on decision-making. We argue that olfactory design interventions might benefit those people in various contexts where sharp decisions are an asset (e.g., operating rooms, court rooms, etc).