Perceiving Auditory Stimuli Impacts Conscious Perception of Electrotactile Stimuli in Older Adults.

Purpose: As individuals age, the ability to perceive and interpret tactile stimuli declines, impacting daily function and quality of life. One factor contributing to this decline is cognitive-perceptual load, which refers to the demand placed on limited cognitive resources allocated for processing and attending to sensory stimuli. This study investigates the modulation of cognitive-perceptual load on tactile detection and gap detection in older adults, incorporating concurrent auditory stimuli to replicate real-world multi-sensory environments. Methods: Detection and gap detection of electrotactile stimuli applied to the skin were assessed in two studies, examining a total of 26 right arm dominant older adults. Participants completed tactile detection and gap detection tasks under two conditions, with and without concurrent auditory stimuli. Results: Detecting auditory stimuli significantly impacted the variance of electrotactile stimuli detection (p<0.001), but not mean (p=0.145). In contrast, discriminating auditory stimuli significantly impacted the mean of electrotactile stimuli gap detection (p<0.001), but not variance (p=0.698). Arm dominance significantly impacted the mean of electrotactile stimuli gap detection (p=0.011), but not detection (p=0.936). Participant age significantly impacted the mean of electrotactile stimuli detection (p=0.018), but not gap detection (p=0.558). Conclusion: This work highlights the importance of accounting for cognitive-perceptual load when assessing tactile perception in older adults. Future work can further explore the influence of cognitive-perceptual load in clinical populations (e.g., following a brain injury), and examine additional factors that influence conscious tactile perception.