The Role of Somatosensory Information in Speech Perception: Imitation Improves Recognition of Disordered Speech

• Published in: Journal of speech, language, and hearing research language, and hearing research, 2015-12, Vol.58 (6), p.1708-1716
• Main Authors: Borrie, Stephanie A, Schäfer, Martina C. M
• Format: Article
• Language: English
• Subjects: Acoustic Stimulation; Acoustics; Adult; Articulation Impairments; Auditory Perception; Comparative Analysis; Control Groups; Dysarthria - therapy; Experimental Groups; Feedback; Feedback (Response); Feedback, Psychological; Feedback, Sensory; Female; Health aspects; Humans; Imitation; Imitative Behavior; Information processing; Instructional Effectiveness; Intelligibility; Learning; Learning Processes; Male; Paradigms; Pattern Recognition, Physiological; Physiological aspects; Pretests Posttests; Reading; Recognition (Psychology); Second language learning; Sensory perception; Somatosensory system; Speech; Speech disorders; Speech Perception; Speech Production Measurement; Studies; Teaching Methods; Training; Treatment Outcome; Visual Perception; Visual task performance; Young Adult
• ISSN: 1092-4388; 1558-9102
• DOI: 10.1044/2015_JSLHR-S-15-0163

Purpose: Perceptual learning paradigms involving written feedback appear to be a viable clinical tool to reduce the intelligibility burden of dysarthria. The underlying theoretical assumption is that pairing the degraded acoustics with the intended lexical targets facilitates a remapping of existing mental representations in the lexicon. This study investigated whether ties to mental representations can be strengthened by way of a somatosensory motor trace. Method: Following an intelligibility pretest, 100 participants were assigned to 1 of 5 experimental groups. The control group received no training, but the other 4 groups received training with dysarthric speech under conditions involving a unique combination of auditory targets, written feedback, and/or a vocal imitation task. All participants then completed an intelligibility posttest. Results: Training improved intelligibility of dysarthric speech, with the largest improvements observed when the auditory targets were accompanied by both written feedback and an imitation task. Further, a significant relationship between intelligibility improvement and imitation accuracy was identified. Conclusions: This study suggests that somatosensory information can strengthen the activation of speech sound maps of dysarthric speech. The findings, therefore, implicate a bidirectional relationship between speech perception and speech production as well as advance our understanding of the mechanisms that underlie perceptual learning of degraded speech.