Auditory and Visual Distractors Decrease Temporal Acuity in a Crossmodal Temporal OrderJudgment Task

Science Center A247

Our ability to synthesize information across multiple senses (multisensory integration; MSI) is essential to our understanding of the world around us. Sensory events that occur close in time are likely to be integrated, and our ability to precisely discriminate the relative timing of unisensory stimuli (crossmodal temporal acuity) influences the accuracy of MSI. Several research groups have reported that disruptions in temporal acuity may contribute to developmental disorders such as autism and dyslexia; however, little is known about how cognitive factors such as attention alter temporal acuity. The current study seeks to determine whether auditory and visual distractors decrease crossmodal temporal acuity using a crossmodal temporal order judgment (CTOJ) task in which participants reported the relative onset of a flash and beep while concurrently completing a visual or auditory distractor task which varied in difficulty. We found that increasing the difficulty of both the auditory and visual distractor tasks decreased participants’ ability to discriminate small differences in timing. Additionally, we found that participants were more strongly affected by the distractor task when the beep was presented before the flash and when the distractors were auditory. The results of this study indicate that distracting attention disrupts crossmodal temporal acuity and that there may be stimulus-specific influences on this effect. The results of this study improve our understanding of how cognitive factors influence MSI. Future studies are needed to determine the neural mechanisms of this disruption and its contribution to developmental disorders.