A Verification Task with Lateralized Tones and Accelerated Speech

Research has suggested that the left hemisphere of the brain may be specialized for processing auditory speech, whereas the right hemisphere may be specialized for processing nonspeech auditory stimuli. Due to contralaterality in auditory pathways, this functional specialization has been reflected in behavioral advantages for speech stimuli presented to the right ear and for nonspeech stimuli presented to the left ear. We used a verification task with lateralized presentations of brief tonal stimuli (sonifications) and accelerated speech stimuli (spearcons) to examine performance as a function of the presentation ear and the type of auditory display. The general pattern of results showed that reaction time and accuracy were facilitated when two accelerated speech stimuli were compared to each other. Based on the results of this study, reported effects of left and right ear advantages do not seem to be robust enough to warrant general ergonomic recommendations (i.e., left ear presentation of nonspeech sounds and right ear presentation of speech sounds) for auditory display design.