Impact of an auditory cognitive load on consciously perceiving electrotactile stimuli in young adults

Tactile perception plays a critical role in sensorimotor integration and functional task performance. Consequently, the various factors, and their interactions, that influence tactile perception are of interest when considering daily function. One such factor, cognitive-perceptual load, is of particular interest, as it reflects the mental demands placed on an individual during complex, multisensory tasks. To examine this cognitive-perceptual factor, this study evaluated how discriminating auditory stimuli impacts tactile detection and discrimination while also considering additional factors including arm dominance, sex, and age.

Participants completed a series of electrotactile detection and discrimination tasks under single (tactile only) and dual (tactile and auditory) conditions. Auditory stimuli were introduced via a partial auditory Stroop test. Secondary factors of interest included arm dominance, sex, stimulation site, and their interactions.

Primary outcomes included electrotactile detection and discrimination thresholds and variability. Detecting electrotactile stimuli while also discriminating auditory stimuli significantly impacted the precision (p = 0.030), yet not threshold (p = 1.000), for detecting the electrotactile stimuli. In contrast, discriminating electrotactile stimuli while also discriminating auditory stimuli significantly impacted the threshold (p<0.001), yet not precision (p = 1.000), in discriminating the electrotactile stimuli. Arm dominance significantly impacted the threshold at which the electrotactile stimuli could be detected (p<0.001) and discriminated (p<0.001). Participant sex and stimulation location (elbow, hand) had a significant interaction effect when detecting (p<0.001), yet not discriminating (p = 1.000) the electrotactile stimuli.

This work examined the impact of a cognitive-perceptual load on perceiving tactile stimuli, and highlighted additional important factors including arm dominance, sex, and stimulation location when assessing tactile perception in young adults. Results suggest that perceiving auditory stimuli increased the variability in detecting electrotactile stimuli. Additionally, perceiving auditory stimuli increased the threshold for discriminating electrotactile stimuli. Future work can expand these investigations to include differing populations including individuals following a neurological injury.