An effect of eye position in cocktail party listening

Previous studies have noted an interaction between eye position and auditory spatial attention, including a tendency to look towards the location of an attended sound (even in the absence of useful visual information). There can also be objective improvements in the detection and discrimination of sounds when the eyes are directed to their location. In the current study, we were interested in whether there is a measurable effect of eye position in “cocktail party” listening situations. We presented five sequences of digits from five loudspeakers positioned at 0 deg,  ± 15 deg, and  ± 30 deg azimuth, and asked participants to repeat back the digits presented from one target loudspeaker. In different blocks of trials, the participant was instructed to visually fixate on the target loudspeaker or on a non-target loudspeaker. Head position was stabilized with a neck-rest, and eye position was tracked continuously to monitor compliance. Performance was best when eye fixation was on-target, and suffered when eye fixation was off-target, particularly for targets located in the center. This result demonstrates an influence of eye position in multitalker mixtures, even in the absence of visual information (lip-reading, etc.), and suggests that optimal performance depends on the spatial alignment of auditory and visual attention.