Assessment of a method for the automatic on/off control of an electrolarynx via lip deformation.
OBJECTIVE
To reduce the inconvenience caused by operating a button-electrolarynx (EL) by hand, we proposed a method for the automatic control of an EL via lip deformation and applied the method to a video-based experimental system (video-EL). The purpose of this study was to validate the method and assess its performance in producing Mandarin Chinese.


METHODS
Eight subjects, including one laryngectomee, were invited to participate in the assessment. First, the empirical parameters of phonation onset/offset estimation were compared with the optimal parameters obtained by minimizing simulation errors during video-EL. Second, a reaction time test was used to evaluate the ability of subjects to pronounce a single word with video-EL. Third, the fluency of subjects in producing long sentences with video-EL was calculated. Finally, the intelligibility of speech produced with video-EL was compared with that produced with button-EL.


RESULTS
The empirical parameters were not significantly different from the optimal parameter and resulted in fewer interruptions during voicing. Video-EL resulted in slower voice initiation and termination when compared with button-EL, which affected the intelligibility of an isolated word. However, video-EL provided a sufficiently fluent voice source so that the intelligibility of speech produced with video-EL was not significantly different from speech produced with button-EL when producing sentences.


CONCLUSIONS
The method proposed in this study is effective in the automatic on/off control of an EL. Subjects produced fluent speech with video-EL that was as intelligible as that produced with button-EL when Mandarin sentences were produced continuously.
The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi' an Jiaotong University, Xi' an 710049, PR China.
Congying
C
Wan
Liang
L
Wu
Huixiong
H
Wu
Supin
S
Wang
Mingxi
M
Wan
D000328:Adult; D000368:Aged; D001331:Automation; D003198:Computer Simulation; D003199:Computer Systems; D005260:Female; D006801:Humans; D007802:Language; D007825:Laryngectomy; D007831:Larynx, Artificial; D008046:Lip / Q000033:anatomy & histology*; D008297:Male; D008422:Materials Testing; D010699:Phonation; D011474:Prosthesis Design; D011930:Reaction Time; D015203:Reproducibility of Results; D013061:Speech Acoustics; D013065:Speech Intelligibility; D013068:Speech Production Measurement; D013071:Speech, Alaryngeal; D013997:Time Factors; D014741:Video Recording; D014832:Voice Disorders / Q000209:etiology / Q000503:physiopathology / Q000523:psychology / Q000534:rehabilitation*; D014833:Voice Quality; D055815:Young Adult