Effect of Visual Load on Auditory Steady-State Response and Subjective Workload

Abstract: Attention can be directed to different modalities such as vision and hearing. Crossmodal attention perspective consider the distribution of simultaneous attention through different senses. It is unclear to which degree task-irrelevant sounds are processed during crossmodal attention. Measuring the auditory steady-state response (ASSR) can determine if and when an auditory threshold is present. Electroencephalogram (EEG) methods allow for measuring early detection of auditory interference during visual tasks. Participants performed a visual target detection task while being exposed to auditory stimuli. The visual task was manipulated in four conditions: no-load, low-load, medium-load, and high-load. NASA-TLX, a self-report workload measure, was used to assess workload difficulty levels. EEG recordings of the 40 Hz ASSR amplitude SNR suggested no visual load effects on the ASSR. Bayesian analysis indicated inconclusive findings and no definite conclusion can therefore be drawn. Current results suggest that basic auditory information does not seem to be easily affected by visual load.