Biasing Saccades With Sound
David McCormick, Pascal Mamassian
Poster
Last modified: 2008-05-13
Abstract
In an audio-visual task, we established that saccade landing-positions are susceptible to bias when a visual target is presented in conjunction with an auditory event at an incongruent location. In our experimental paradigm, the exhibition of this bias is contingent on two additional criteria. First, a simultaneous visual distractor must also be present. Second, observers must have prior knowledge of the overall audio-visual location congruence in the task. Observers were required to perform a saccade toward a cloud of black dots presented at a random, eccentric, screen location. A cloud of white dots was presented simultaneously on the opposite side of the screen. Experiment 1: in 75% of trials, a tone was presented, via headphones, to the ear congruent with the black dots’ location; the remaining 25% of trials contained a tone presented to the ear congruent with the white dots’ location. The frequency of (error) saccades toward white dots increased in incongruent-trials. Experiment 2: audio-visual location congruency was 50%; overall time to saccade onset was increased, but differences in congruent-/incongruent-trial errors were insignificant. In light of the results from experiment 2, we interpret experiment 1’s diverging congruent/incongruent error-rates in terms of attentional cueing, rather than multisensory integration.