IS EAR DIRECTION OR INTEGRATED PERCEIVED DIRECTION DOMINANT FOR SPEECH PERCEPTION? Head rotation effects on the right ear advantage

Abstract: There is a well-documented asymmetry in speech perception, known as the right ear advantage (REA), where speech sounds are better recognised when coming from the right than from the left. This asymmetry is sensitive to multisensory integration, as seen in José Morais’ ventriloquism study. The aim of the present study is to investigate whether speech perception is affected by the integrated perceived direction of self or only by the direction of the ears. Dextral participants (N = 35) were tested in a single response diotic listening task with consonant-vowel-syllables presented in 144 pairs, while instructed to listen in one direction. Each participant was tested in three head direction conditions: straight, left, and right, with the gaze held straight in relation to the seating position in all conditions. A one-way repeated measures ANOVA was run but the null-hypothesis could not be rejected. Stimulus dominance is presented as a likely confounding factor, although other methodological and theoretical errors are certainly possible.