Auditory stroop using spatial stimuli

Abstract

Purpose: The purpose of this study is to evaluate the influence of spatial auditory stimuli when the semantic meaning of the spoken word is incongruent with the location of the sound. Based on previous auditory Stroop research we predict that individuals will respond to incongruent stimuli with reduced accuracy and prolonged reaction times. Methods: Twenty students between the ages of 18-30 were presented with a word indicating a direction that included location cues representing the same or different direction. Stimuli were presented in the horizontal plane (i.e., left, center, right) and in the vertical plane (i.e., up, center, down). Participants were instructed to answer verbally the direction of the sound source rather than the direction the spoken word indicated. Accuracy and reaction times were analyzed in both planes. Results: Generally, for stimuli in the horizontal plane, accuracy was high and reaction times were low, regardless of congruency. However, there was a significantly higher frequency of errors in vertical-congruent conditions than in horizontal conditions. The frequency of vertical- incongruent errors was higher still. The pattern of reaction time results matched the accuracy results. Conclusions: Despite the simulated source angle being well above the minimal audible angle in both planes, the results suggest a lower salience in the vertical domain. If seeking to develop a multi-dimensional auditory map for sound selection, the horizontal plane is most likely to result in the clearest representations of sound-source location.