An investigation of the relation between sibilant production and somatosensory and auditory acuity

• Published in: The Journal of the Acoustical Society of America 2010-11, Vol.128 (5), p.3079-3087
• Main Authors: Ghosh, Satrajit S., Matthies, Melanie L., Maas, Edwin, Hanson, Alexandra, Tiede, Mark, Ménard, Lucie, Guenther, Frank H., Lane, Harlan, Perkell, Joseph S.
• Format: Article
• Language: English
• Subjects: Audition; Auditory Cortex - physiology; Biological and medical sciences; Feedback; Female; Fundamental and applied biological sciences. Psychology; Humans; Linear Models; Male; Perception; Phonation - physiology; Phonetics; Proprioception - physiology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Somatosensory Cortex - physiology; Speech Perception - physiology; Speech Production; Speech Production Measurement; Tongue - physiology; Touch Perception - physiology; Young Adult
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.3493430

The relation between auditory acuity, somatosensory acuity and the magnitude of produced sibilant contrast was investigated with data from 18 participants. To measure auditory acuity, stimuli from a synthetic sibilant continuum ( [ s ] - [ ʃ ] ) were used in a four-interval, two-alternative forced choice adaptive-staircase discrimination task. To measure somatosensory acuity, small plastic domes with grooves of different spacing were pressed against each participant's tongue tip and the participant was asked to identify one of four possible orientations of the grooves. Sibilant contrast magnitudes were estimated from productions of the words 'said,' 'shed,' 'sid,' and 'shid'. Multiple linear regression revealed a significant relation indicating that a combination of somatosensory and auditory acuity measures predicts produced acoustic contrast. When the participants were divided into high- and low-acuity groups based on their median somatosensory and auditory acuity measures, separate ANOVA analyses with sibilant contrast as the dependent variable yielded a significant main effect for each acuity group. These results provide evidence that sibilant productions have auditory as well as somatosensory goals and are consistent with prior results and the theoretical framework underlying the DIVA model of speech production.