Lip-tube Perturbation Research Articles

Vowel production in children with myotonic dystrophy: A lip-tube perturbation study

Myotonic dystrophy, a neurodegenerative disease that causes muscle weakness and difficulties in muscle relaxation after contraction, frequently affects orofacial articulatory dynamics leading to decreased speech intelligibility, particularly in children. We aimed to investigate the effects of myotonic dystrophy on sensorimotor relationships in children’s speech through a study of compensations for a lip-tube perturbation. We recruited fourteen 6- to 14-year-old French-speaking children diagnosed with myotonic dystrophy and 14 aged-matched typically developing children. They were asked to produce repetitions of the vowel /u/ with and without a 15-mm-diameter tube inserted between the lips. A synchronized ultrasound, Optotrak motion tracking system, and audio recording system was used to track lip and jaw displacement as well as tongue shape and position. Separate analyses were conducted on the first (F1), the second formant (F2), and the fundamental frequency (F0). Results revealed a significant main effect of group and an interaction between group and condition. Perceptual ratings of the produced vowels suggest that children with myotonic dystrophy rely more on auditory feedback than their typically developing peers. Together, results suggest that auditory feedback plays an important role in speech compensation, especially when the production system is impaired.Myotonic dystrophy, a neurodegenerative disease that causes muscle weakness and difficulties in muscle relaxation after contraction, frequently affects orofacial articulatory dynamics leading to decreased speech intelligibility, particularly in children. We aimed to investigate the effects of myotonic dystrophy on sensorimotor relationships in children’s speech through a study of compensations for a lip-tube perturbation. We recruited fourteen 6- to 14-year-old French-speaking children diagnosed with myotonic dystrophy and 14 aged-matched typically developing children. They were asked to produce repetitions of the vowel /u/ with and without a 15-mm-diameter tube inserted between the lips. A synchronized ultrasound, Optotrak motion tracking system, and audio recording system was used to track lip and jaw displacement as well as tongue shape and position. Separate analyses were conducted on the first (F1), the second formant (F2), and the fundamental frequency (F0). Results revealed a significant main effec...

Effect of simultaneous lip-tube and auditory feedback perturbations

In a series of previous experiments, it has been shown that when required to produce the back rounded vowel /u/ with a lip-tube perturbation that prevents lip rounding, speakers reached the auditory goal associated with /u/ by altering their tongue position. In the present study, the importance of sensory feedback was further investigated by combining lip-tube and auditory feedback perturbations. Fifteen adult francophone speakers produced 5 blocks of ten /u/ tokens under various conditions (following and preceding a baseline condition). First, tokens were produced when the speakers had a lip-tube in place (predicted to increase F1 and F2) as well as a real-time auditory feedback perturbation (designed to cancel the acoustic effects of the lip-tube, that is, to decrease F2 and F1). Next, only the lip-tube perturbation was applied, with and without white noise. Formant values for each condition were extracted at the vowel midpoint. Although most speakers produced a larger compensatory response with the lip-tube alone condition than with the combined lip-tube and auditory perturbation condition, all speakers produced altered formants in the latter condition. This suggests that speakers try to reduce auditory and somatosensory feedback errors during speech production, with a speaker-specific weighting of each sensory modality.

Compensation for a lip-tube perturbation in 4-year-olds: Articulatory, acoustic, and perceptual data analyzed in comparison with adults

The nature of the speech goal in children was investigated in a study of compensation strategies for a lip-tube perturbation. Acoustic, articulatory, and perceptual analyses of the vowels /y/ and /u/ produced by ten 4-year-old French speakers and ten adult French speakers were conducted under two conditions: normal and with a large tube inserted between the lips. Ultrasound and acoustic recordings of isolated vowels were made in the normal condition before any perturbation, for each of the trials in the perturbed condition, and in the normal condition after the perturbed trials. Data revealed that adult participants moved their tongues in the perturbed condition more than children did. The perturbation was generally at least partly compensated for during the perturbed trials in adults, but children did not show a typical learning effect. In particular, unsystematic improvements were observed during the sequence of perturbed trials, and after-effects were not clear in the articulatory domain. This suggests that children may establish associative links between multisensory phonemic representations and articulatory maneuvers, but those links may mainly rely on trial-to-trial, error-based feedback correction mechanisms rather than on the internal model of the speech production apparatus, as they are in adults.

Effects of blindness on production–perception relationships: Compensation strategies for a lip-tube perturbation of the French [u

ABSTRACTThe impact of congenital visual deprivation on speech production in adults was examined in an ultrasound study of compensation strategies for lip-tube perturbation. Acoustic and articulatory analyses of the rounded vowel /u/ produced by 12 congenitally blind adult French speakers and 11 sighted adult French speakers were conducted under two conditions: normal and perturbed (with a 25-mm diameter tube inserted between the lips). Vowels were produced with auditory feedback and without auditory feedback (masked noise) to evaluate the extent to which both groups relied on this type of feedback to control speech movements. The acoustic analyses revealed that all participants mainly altered F2 and F0 and, to a lesser extent, F1 in the perturbed condition – only when auditory feedback was available. There were group differences in the articulatory strategies recruited to compensate; while all speakers moved their tongues more backward in the perturbed condition, blind speakers modified tongue-shape parameters to a greater extent than sighted speakers.

Exploring consequences of short- and long-term deafness on speech production: A lip-tube perturbation study

Studies have reported strong links between speech production and perception. We aimed to evaluate the role of long- and short-term auditory feedback alteration on speech production. Eleven adults with normal hearing (controls) and 17 cochlear implant (CI) users (7 pre-lingually deaf and 10 post-lingually deaf adults) were recruited. Short-term auditory feedback deprivation was induced by turning off the CI or by providing masking noise. Acoustic and articulatory measures were obtained during the production of /u/, with and without a tube inserted between the lips (perturbation), and with and without auditory feedback. F1 values were significantly different between the implant OFF and ON conditions for the pre-lingually deaf participants. In the absence of auditory feedback, the pre-lingually deaf participants moved the tongue more forward. Thus, a lack of normal auditory experience of speech may affect the internal representation of a vowel.

Exploring production-perception relationships in normal hearing and cochlear implant adults: A lip-tube perturbation study

It has been claimed that auditory feedback mechanisms enable monitoring and calibration of feedforward commands in speech production. Therefore, lack of auditory feedback may interfere with adequate compensation strategies in perturbed situations. This study investigates the effect of hearing status and a lip tube perturbation on vowel production. Eleven normal-hearing controls, and seventeen cochlear implant (CI) users (7 prelingually, 10 postlingually) were recorded during the production of the vowel /u/. Acoustic analyses were conducted with and without a 15-mm-diam tube inserted between the lips. Recording sessions were also made before and after the perturbation, with and without auditory feedback. Deaf participants’ auditory feedback was provided by the CI and interrupted by switching off their implant devices. Separate analyses were conducted on the first (F1), the second formant (F2), and the fundamental frequency (F0). Results revealed a main effect of group and an interaction between condition and hearing status. Together, results suggest that auditory feedback plays an important role in speech compensation.

The role of auditory feedback in speech development: A study of compensation strategies for a lip-tube perturbation

The role of auditory feedback in speech development was investigated through a study of compensation strategies for a lip-tube perturbation. Acoustic, articulatory, and perceptual analyses of the vowels /i/, /y/, and /u/ produced by ten 4-year-old French speakers and ten adult French speakers were conducted under two conditions: normal and with a 15-mm-diameter tube (for /y/ and /u/) or a 5-mm-diameter tube (for /i/) inserted between the lips. Ultrasound and acoustic recordings of isolated vowels were made in normal condition before any perturbation (N1), for each of the 20 trials in the perturbed condition (P), and in normal condition after the perturbed trials (N2). Data reveal that adult participants moved their tongue in the P condition more than children subjects, to compensate for F1 and F2 alteration induced by the tube. Except for /y/, the perturbation was generally at least partly compensated during the perturbed trials in adults and children, but children did not show a typical learning effect. Results are analyzed from the perspective of (i) goal specification in speech production in the acoustic and/or somatosensory domain, and (ii) the maturity of representations of the motor apparatus in the brain.

Compensation strategies for a lip-tube perturbation of French [u]: An acoustic and perceptual study of 4-year-old children

The relations between production and perception in 4-year-old children were examined in a study of compensation strategies for a lip-tube perturbation. Acoustic and perceptual analyses of the rounded vowel [u] produced by twelve 4-year-old French speakers were conducted under two conditions: normal and with a 15-mm-diam tube inserted between the lips. Recordings of isolated vowels were made in the normal condition before any perturbation (N1), immediately upon insertion of the tube and for the next 19 trials in this perturbed condition, with (P2) or without articulatory instructions (P1), and in the normal condition after the perturbed trials (N2). The results of the acoustic analyses reveal speaker-dependent alterations of F1, F2, and/or F0 in the perturbed conditions and after the removal of the tube. For some subjects, the presence of the tube resulted in very little change; for others, an increase in F2 was observed in P1, which was generally reduced in some of the 20 repetitions, but not systematically and not continuously. The use of articulatory instructions provided in the P2 condition was detrimental to the achievement of a good acoustic target. Perceptual data are used to determine optimal combinations of F0, F1, and F2 (in bark) related to these patterns. The data are compared to a previous study conducted with adults [Savariaux et al., J. Acoust. Soc. Am. 106, 381-393 (1999)].