Speech and Swallow Kinematics of a Person with Congenital Aglossia

Abstract

Objective: This research study explored movement of key processes during speech and swallow of a person with congenital aglossia. It expands upon earlier studies that found a high degree of intelligibility among listeners for expressive speech by the person with congenital aglossia and seeks to identify the dynamics through which the articulators accomplish this phenomenon.Methods: Positional movements of the mandible and hyoid bone and mylohyoid and tongue base for speech and swallow were compared with those movements obtained for people without aglossia. Results:In this subject, the hyoid bone and mandible were strongly associated with movement of the pseudo tongue for both speech and swallow. This is markedly different from results of normal subjects, who show strong correlations between the hyoid bone and mandible and the tongue for swallow only. Kinematics differed significantly for speech and swallow tasks in the person with PwCA, with the exception of the hyoid bone, which behaved in a similar manner for both tasks. Movements of pseudo-tongue structures demonstrated a variety of horizontal and vertical movements, with some independent relationships between mandibular and hyoid bone motions for both oral swallow and speech. Overall, the dependent variables of mylohyoid and the base of tongue were closely related to the movement of the hyoid bone, which was the strongest determinant of vertical dependent variable movement. Results revealed that in this person with congenital aglossia, the hyoid bone and mandible were strongly associated with movement of the pseudo tongue for both speech and swallow. This is markedly different from results of normal subjects, who show strong correlations between the hyoid bone and mandible and the tongue for swallow only. Conclusion:These results suggest that speakers who present with congenital or acquired structural and/or physiological reductions to the speech mechanism may present with the capacity to capitalize on a variety of actions during eating or swallowing to optimize the more finessed actions of speech. The highly predictable correlations of muscles for deglutition and speech suggest that this speaker essentially 'bootstrapped' muscular actions (and limitations therein) developed for deglutition and used them to buttress speech and resonance. These actions are quite different from those of individuals with a tongue, who recruit a variety of muscles for the diverse acts of speaking and swallowing.

Bilabial Substitution Patterns during Consonant Production in a Case of Congenital Aglossia

“…The absence of the tongue was compensated for by the fact that the floor of the mouth (mylohyoid) and base of the tongue were hypertrophied and could independently and symmetrically be elevated to contact the palate during speech and swallow [18,19]. There was no evidence of hyper-or hypo-nasality as a resonatory characteristic [14,15].…”

“…Only 11 cases have been reported internationally [1][2][3][4][5][6][7][8][9][10][11] since it was first described systematically by De Jussieu in 1718 [12] whose original paper was investigated and described by Salles et al in 2016 [13]. McMicken and her co-authors [13][14][15][16][17][18][19][20] have reported extensively on research from cinefluorographic films and audio-visual (AV) recordings collected in 1986 on a 16-year-old female PwCA. This research included perception of vowel production [14], perception of consonant production [15], and cinefluorographic examination of articulation [16], in addition to current re-examination of the PwCA, now in her 40s, with electropalatography [17], videoflourography of articulatory movements of pseudo tongue, hyoid and mandible [18], and speech and swallowing kinematics [19].…”

“…McMicken and her co-authors [13][14][15][16][17][18][19][20] have reported extensively on research from cinefluorographic films and audio-visual (AV) recordings collected in 1986 on a 16-year-old female PwCA. This research included perception of vowel production [14], perception of consonant production [15], and cinefluorographic examination of articulation [16], in addition to current re-examination of the PwCA, now in her 40s, with electropalatography [17], videoflourography of articulatory movements of pseudo tongue, hyoid and mandible [18], and speech and swallowing kinematics [19]. It should be noted that the PwCA was a co-author in previous articles and is currently the subject of this paper.…”

“…The PwCA I was re-examined by McMicken et al [16][17][18][19] and articulatory movements for speech and swallowing were studied using electropalatography (EPG) and videofluorographic films. These results suggested PwCA I may present with the capacity to capitalize on a variety of actions during eating or swallowing to optimize the more refined movements of speech.…”

Articulatory Movement during Production of Lingua-Alveolar Stop Consonants in a Case of Congenital Aglossia

“…Fortunately, in 1986, one person with CA (PwCA) was identified, and became the participant of subsequent research based on cineradiographic films (CRFs), audio/ visual recordings, videoflouroscopy, electropalatography (EPG), taste testing, and in-vivo analysis that has provided a wealth of information regarding the adaptations in vocal tract resonance characteristics, modifications to articulatory processes, alternate neurological pathways to taste discrimination, and altered patterns of chewing and swallowing. Five previous manuscripts have detailed this research [4][5][6][7][8]. The current manuscript discusses an investigation into the production of the lingua-alveolar stop consonants, /t/ and /d/, produced by the PwCA and the specific anatomical and physiological properties and the kinematics involved in these intelligible articulatory productions.…”