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Purpose The purpose of this article is to provide a review of the neck-type electrolarynx, describe acoustic and perceptual characteristics of electrolaryngeal speech, and highlight the potential impact of electrolaryngeal speech on voice-related quality of life postlaryngectomy, concluding by describing efforts to improve electrolaryngeal speech rehabilitation. Although several alaryngeal communication options exist, the electrolarynx is the most readily available means of producing voice and speech postlaryngectomy. This is due to the small and handheld nature of an electrolaryngeal device, which is commonly placed against the neck during use. Research suggests that approximately half of laryngectomees use an electrolarynx up to 2 years postlaryngectomy. Conclusion Given the importance of the electrolarynx postlaryngectomy, decisions should be made in conjunction with the laryngectomee. It is important to ask: Why not an electrolarynx?

Purpose The purpose of this study was to determine listeners' ability to learn talker identity from speech produced with an electrolarynx, explore source and filter differentiation in talker identification, and describe acoustic-phonetic changes associated with electrolarynx use. Method Healthy adult control listeners learned to identify talkers from speech recordings produced using talkers' normal laryngeal vocal source or an electrolarynx. Listeners' abilities to identify talkers from the trained vocal source (Experiment 1) and generalize this knowledge to the untrained source (Experiment 2) were assessed. Acoustic-phonetic measurements of spectral differences between source mechanisms were performed. Additional listeners attempted to match recordings from different source mechanisms to a single talker (Experiment 3). Results Listeners successfully learned talker identity from electrolarynx speech but less accurately than from laryngeal speech. Listeners were unable to generalize talker identity to the untrained source mechanism. Electrolarynx use resulted in vowels with higher F1 frequencies compared with laryngeal speech. Listeners matched recordings from different sources to a single talker better than chance. Conclusions Electrolarynx speech, although lacking individual differences in voice quality, nevertheless conveys sufficient indexical information related to the vocal filter and articulation for listeners to identify individual talkers. Psychologically, perception of talker identity arises from a “gestalt” of the vocal source and filter.

Purpose To determine (a) the effect of fundamental frequency (f 0 ) on speech intelligibility, acceptability, and perceived gender in electrolaryngeal (EL) speakers, and (b) the effect of known gender on speech acceptability in EL speakers. Method A 2-part study was conducted. In Part 1, 34 healthy adults provided speech recordings using electrolarynges set at 75 Hz, 130 Hz, and 175 Hz, and 36 listeners transcribed the recordings. In Part 2, 22 speech samples were presented to 16 listeners. First, listeners identified the gender of each speaker and judged his or her speech acceptability using rating scales. Second, listeners judged the same samples for speech acceptability when gender information was provided. Results In Part 1, speakers were significantly more intelligible when using 75-Hz devices. In Part 2, the f 0 of the speech signal significantly impacted listeners' accuracy in perceiving the speaker’s gender: In gender-incongruent conditions (males using 175-Hz devices, females using 75-Hz devices), listeners were unable to identify female speakers. Speech acceptability judgments were directly related to intelligibility. Finally, listeners differentially penalized female speakers who used 75-Hz devices when gender information was known. Conclusion Low f 0 facilitated speech intelligibility. However, at low f 0 , listeners were unable to identify females as female, and females were differentially penalized for speech acceptability. Results may have implications for rehabilitation.

Purpose The electrolarynx (EL) is a widely used device for alaryngeal speech, but it requires manual operation and produces voice that typically has a constant fundamental frequency. An electromyographically controlled EL (EMG-EL) was designed and implemented to provide hands-free control with dynamic pitch modulation. Method Three participants who underwent total laryngectomy surgery and 4 participants with normal voice were trained to produce EMG-EL speech through a multiple-baseline, successive-stage protocol. Baseline performance was established through 3 testing probes, followed by multiple hour-long training sessions. Results At the end of the training, all participants learned to initiate, sustain, and terminate EMG-EL activation in correspondence with articulation, and most were able to modulate the pitch to produce intonational contrasts. After completing the testing/training protocol, 1 of the 3 participants who underwent total laryngectomy was encouraged to independently use the EMG-EL at his residence. This participant sustained his performance for an additional 6 weeks and also used the EMG-EL successfully to communicate over the phone. Conclusions Our findings suggest that some participants with laryngectomies and vocally normal individuals can learn to produce hands-free speech using the EMG-EL device within a few hours and that significant additional gains in device control (particularly pitch modulation) are attainable through subsequent training sessions.

Artificial larynges provide a means of verbal communication for people who have either lost or are otherwise unable to use their larynges. Although they enable adequate communication, the resulting speech has an unnatural quality and is significantly less intelligible than normal speech. One of the major problems with the widely used Transcutaneous Artificial Larynx (TAL) is the presence of a steady background noise caused by the leakage of acoustic energy from the TAL, its interface with the neck, and the surrounding neck tissue. The severity of the problem varies from speaker to speaker, partly depending upon the characteristics of the individual's neck tissue. The present study tests the hypothesis that TAL speech is enhanced in quality (as assessed through listener preference judgments) and intelligibility by removal of the inherent, directly radiated background signal. In particular, the focus is on the improvement of speech over the telephone or through some other electronic communication medium. A novel adaptive filtering architecture was designed and implemented to remove the background noise. Perceptual tests were conducted to assess speech, from two individuals with a laryngectomy and two normal speakers using the Servox TAL, before and after processing by the adaptive filter. A spectral analysis of the adaptively filtered TAL speech revealed a significant reduction in the amount of background source radiation yet preserved the acoustic characteristics of the vocal output. Results from the perceptual tests indicate a clear preference for the processed speech. In general, there was no significant improvement or degradation in intelligibility. However, the processing did improve the intelligibility of word-initial non-nasal consonants.

Past investigations of alaryngeal speech intelligibility have focused on comparative intelligibility as perceived by young normally hearing adults. However, the spouses and social companions of laryngectomees may have significantly different auditory capabilities compared to young listeners. This report presents a comparison of alaryngeal and laryngeal speech identification performance for a group of young normally hearing listeners and a group of older adult listeners representative of the age of the laryngectomee's social companions. The speech signals investigated included normal laryngeal speech, artificial larynx speech, traditional esophageal speech, and tracheoesophageal speech. The results obtained reveal not only differences in speech signals but also a difference in the proficiency of speech perception for the two groups, favoring the younger listeners. The results of the speech identification measures in the presence of auditory competition revealed greatest intelligibility for the artificial larynx speech signal and poorest for the tracheoesophageal speech signal.

A modification of the Western Electric #5 A electrolarynx is described and evaluated. The modification involved insertion of a bypass plug into the circuitry of this neck-type instrument thus converting it to a mouth-type electrolarynx. Intensity readings at the one-third octaves and intelligibility data were obtained with the modified instrument and with a Cooper-Rand electrolarynx. The instruments were judged to be equal in overall performance.

Speech samples obtained from a group of adult males and females while they articulated the tone produced by a single-frequency electrolarynx were played to a panel of listeners who were asked to determine the sex of each speaker. Formant frequencies for the vowels /i/ and /u/ produced in isolation by the same speakers were obtained by spectrographic analysis. The judges were able to correctly identify the sex of the speakers 88% of the time, and vowel formant frequency averages were closely associated with the degree of male or female quality in these voices. These findings indicate that in the absence of between-subject variations in laryngeal fundamental frequency, a distinct cue to speaker sex may be contained in the individual vocal tract resonances.

The use of the electrolarynx to facilitate communication with patients having temporary tracheostomies is discussed. Five case histories are presented with a discussion of the indications and contraindications for the use of the electrolarynx. It is concluded that the electrolarynx can be used effectively by selected patients with temporary tracheostomy tubes.

Laryngo-esophagectomy was performed with a colon transplant to replace the excised esophagus. The patient did not develop functional “colonic” speech but does function adequately using an artificial larynx. Cineradiologic evidence reveals that the transplanted segment of colon permits development of a pseudoglottis to produce sound. He was capable of injecting air and forming the pseudoglottis, but he interfered with the production of colonic voice by retropositioning his tongue to close the hypopharynx.

This report provides basic information about a relatively unknown pneumatic artificial larynx called the Tokyo artificial larynx. Part of the report describes a clinical study of a highly skilled American user of the Tokyo larynx. Descriptive information is provided about important acoustic and perceptual characteristics of speech produced with this Japanese-made device.