Unisensory temporal processing abilities across modalities in neurotypical children and young adults

Sensory signals from multiple modalities presented close in time are often integrated, building a coherent and meaningful multisensory perceptual world. A better understanding of our perception requires characterization of how the nervous system detects and encodes unisensory cues in time. There are very few studies that have focused on the development and individual variabilities in temporal aspects of unisensory signal processing in neurotypical populations across modalities. Using a temporal order judgment (TOJ) task, this study explored individual differences in the temporal processing of unisensory (auditory, tactile, and visual) stimuli in neurotypical children and young adults. We examined whether the precision of unisensory temporal processing and perceptual synchrony for unisensory stimuli can be influenced by participants' age, cognition, and sensory responsiveness profiles. Performance in each of the unisensory TOJ tasks, measured in temporal order judgment threshold (JND) and reaction time (RT), showed significant improvement with age. On the other hand, perceptual synchrony, measured in Point of Subjective Simultaneity (PSS), remained stable with age across modalities. Although cognitive abilities and sensory responsiveness patterns could not predict the individual variability in unisensory temporal precision or perceptual synchrony for this group of subjects, results from this study show a developmental trajectory of unisensory temporal sensitivity from childhood to young adulthood.