The benefit of acoustic beamforming in solving the “cocktail party problem” for persons with acquired aphasia

Abstract

Acoustic beamforming has been shown to improve identification of target speech in noisy listening environments for individuals with sensorineural hearing loss. This study examined whether beamforming would provide a similar benefit for individuals with aphasia (an acquired neurological language deficit). Persons with aphasia (PWA) are known to exhibit impaired language comprehension abilities; however, most work on language comprehension in PWA has been conducted in quiet settings, and little is known about the impact of competing auditory information on performance. In this study, we measured the intelligibility of target speech masked by other speech or noise for two presentation/microphone conditions: one condition, designated “KEMAR,” provided natural spatial cues via KEMAR impulse responses; the second condition, designated “BEAM,” enhanced the target speech level via a single-channel beamformer. In each condition, subjects heard a target sentence at 0 deg azimuth concurrent with two independent maskers—speech or speech-shaped speech-envelope-modulated noise—from ±60 deg. Threshold target-to-masker ratios were measured adaptively for each subject, with individually-determined modifications in the procedures made for the subjects. Results indicated substantially lower (better) thresholds for the beamformer condition than for KEMAR, providing preliminary evidence that PWA may benefit from the use of acoustic beamforming in complex, multiple-source listening situations.