Adaptation to distorted speech: The effects of hearing loss and hearing aids

Abstract

Adaptation, or rapid performance gains with repeated exposure, is one of the processes that supports the recognition of speech in challenging listening conditions. Age-related hearing loss is associated with substantial declines in speech recognition in challenging conditions. It is not clear whether age-related hearing loss relates to adaptation and whether adaptation is influenced by a hearing-aid. To this end, we characterized adaptation to time-compressed speech and speech in babble noise in a group of 57 participants (ages 60–90) that were tested both with and without hearing aids fitted by an audiologist just before the assessment. Significant adaptation occurred in both speech conditions. Speech in noise recognition accuracy improved by approximately 15% over the course of listening to 16 sentences with hearing aids but remained stable without the hearing aids (OR = 1.24). The rate of adaptation did not depend on hearing. Adaptation to time-compressed speech also occurred only with the hearing aids (improvement of ∼10%, OR = 1.32). Adaptation was stronger in listeners with poorer hearing (OR = 1.18), perhaps due to their poor starting accuracy. Together, these data suggest that amplification can contribute to speech adaptation even in inexperienced hearing aid users.