Olfactory training improves emotion matching ability in 6–9 years old children — preliminary evidence

Abstract

Emotion knowledge involves the ability to recognize and express emotions and understand emotional processes. The neural substrates of emotion knowledge include i.a. the amygdala, orbitofrontal cortex, and anterior cingulate cortex. These structures are also involved in processing olfactory stimuli and their volume and functional activity have been shown to increase after a period of regular olfactory stimulation (olfactory training, OT). We verified if OT will improve one aspect of emotion knowledge — the ability to match emotional facial expressions. Eighty-three children (39 boys) aged 6–9 years were randomly assigned either to an OT group (OTG) that smelled a set of four odors (lemon, cloves, eucalyptus, rose) twice a day for 12 weeks or to a placebo group that performed the training with odorless stimuli. Children in the OTG (n = 40) matched emotional facial expressions significantly better after OT as compared with their baseline score. This effect was not present in the placebo group (n = 43) whose scores remained the same after OT. Practical applications: This novel finding suggests the potential of olfactory stimulation in supporting emotion knowledge in children and bridges recent findings in sensory studies, psychophysiology, and emotional development. Further studies are necessary to delineate which aspects of emotion knowledge might be enhanced by OT. In future, OT might be potentially included in programs designed for groups with specific emotion knowledge deficits.