Auditory discrimination of speech stimuli is an essential tool in speech and language therapy, e.g., in dysarthria rehabilitation. It is unclear, however, which listener characteristics are associated with the ability to perceive differences between one's own utterance and target speech. Knowledge about such associations may help to support patients participating in speech and language therapy programs that involve auditory discrimination tasks.
Discrimination performance was evaluated in 96 healthy participants over 60 years of age as individuals with dysarthria are typically in this age group. Participants compared meaningful words and sentences on the dimensions of loudness, pitch and speech rate. Auditory abilities were assessed using pure-tone audiometry, speech audiometry and speech understanding in noise. Cognitive measures included auditory short-term memory, working memory and processing speed. Linguistic functioning was assessed by means of vocabulary knowledge and language proficiency.
Exploratory factor analyses showed that discrimination performance was primarily associated with cognitive and linguistic skills, rather than auditory abilities. Accordingly, older adults’ discrimination performance was mainly predicted by cognitive and linguistic skills. Discrimination accuracy was higher in older adults with better speech understanding in noise, faster processing speed, and better language proficiency, but accuracy decreased with age. This raises the question whether these associations generalize to clinical populations and, if so, whether patients with better cognitive or linguistic skills may benefit more from discrimination-based therapeutic approaches than patients with poorer cognitive or linguistic abilities.