When auditory and visual signal processing conflict: cross-modal interference in extended work periods

Abstract

Auditory and visual stimuli presented at intervals of about 300 m sec often produce miss errors in one or the other channel, which result from a bottleneck in a neural circuit associated with executive memory. The present study examined the possibility that cross-modal interference could carry over to performance units that transpire over 3 min or longer. An N-back task performed by 113 undergraduates with simultaneous auditory and visual stimuli was organised into 1-min blocks of 20 trials in 2-back and 3-back conditions. Results showed that impairment of visual processing was more frequent than impairment of auditory processing under conditions of fatigue. A substantial number of person blocks showed no such interference, however. Bottlenecks during early stages of processing may have more extensive effects on later processing than previously recognised. Further research should consider perceptual cycling in longer term tasks involving complex stimuli.