Articulation lost in space. The effects of local orobuccal anesthesia on articulation and intelligibility of phonemes

• Published in: Brain and language Vol. 207; p. 104813
• Main Authors: De Letter, Miet, Criel, Yana, Lind, Andreas, Hartsuiker, Robert, Santens, Patrick
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.08.2020
• Subjects: Administration, Buccal; Adult; Aerospace Engineering; Anesthesia - adverse effects; Anesthesia - methods; Anesthetics - administration & dosage; Anesthetics - adverse effects; Ataxia; Biofeedback, Psychology - drug effects; Cerebellum; Cognition; Control Engineering; Dysarthria; Dysarthria - chemically induced; Electrical Engineering, Electronic Engineering, Information Engineering; Elektroteknik och elektronik; Engineering and Technology; Farkost och rymdteknik; Feedback; Female; Humans; Intelligibility; Male; Maskinteknik; Mechanical Engineering; Motor speech; Phonetics; Psychomotor Performance - drug effects; Reglerteknik; Rymd- och flygteknik; Somatosensory; Speech - drug effects; Speech Intelligibility - drug effects; Speech Production Measurement; Teknik; Vehicle and Aerospace Engineering; Somatosensory; Cerebellum; Feedback; Intelligibility; Ataxia; Motor speech; Dysarthria
• ISSN: 0093-934X; 1090-2155; 1090-2155
• DOI: 10.1016/j.bandl.2020.104813

•Interference with oral somatosensory feedback decreases speech intelligibility.•Consonant formation is more affected than vowel formation.•Decreased oral somatosensation affects rapid and precise articulatory movements. Motor speech requires numerous neural computations including feedforward and feedback control mechanisms. A reduction of auditory or somatosensory feedback may be implicated in disorders of speech, as predicted by various models of speech control. In this paper the effects of reduced somatosensory feedback on articulation and intelligibility of individual phonemes was evaluated by using topical anesthesia of orobuccal structures in 24 healthy subjects. The evaluation was done using a combination of perceptual intelligibility estimation of consonants and vowels and acoustic analysis of motor speech. A significantly reduced intelligibility was found, with a major impact on consonant formation. Acoustic analysis demonstrated disturbed diadochokinesis. These results underscore the clinical importance of somatosensory feedback in speech control. The interpretation of these findings in the context of speech control models, neuro-anatomy and clinical neurology may have implications for subtyping of dysarthria.