From Odors to Colors: Sensory Perception in Neurodiverse Mexican Youth

Previous work has shown that humans make consistent associations between odor and color. However, neurodiverse individuals, especially those with autism spectrum disorder (ASD), perceive and interpret sensory information differently from their neurotypical peers. Their sensory perceptual experiences can involve hypersensitivity or hyposensitivity, as well as deficits in multisensory integration, especially among younger individuals. In this study, we evaluated olfactory-visual associations among verbal individuals with ASD, attention deficit/hyperactivity disorder (ADHD), and a comparison group of children without neurodevelopmental disorders by means of an odor-color association task. We found that youth with ASD, ADHD, and without neurodevelopmental disorders experience olfactory perception in a similar manner, showing similar inconsistencies in terms of (verbal) odor identification and odor-color associations, while rating odors similarly in terms of (un)pleasantness, specifically for sour, salty, and spicy odors and sweet and fruity odors. This supports the notion that neurodivergent youth present individual variation in olfaction, but less so in perceived odor pleasantness, results that promote further exploration of odor-color associations within and across diverse populations.