EMG Voice Restoration
Phase: NA
Conditions: Rehabilitation of Speech and Language Disorders, Speech Disorders, Speech, Alaryngeal, Communication Aids for Disabled, Speech Perception, Speech Intelligibility
Sponsor: Altec Inc.

Informed Consent Form 
 
“MyoVoice to Restore Natural, Hands-free Communication to 
Individuals With Vocal Impairments” 
 
NCT04762043 
 
Approved 06-26-23 
 
 

Protocol Summary for R44DC017097 
 
 
 
 
 
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Study Title: “EMG Voice Restoration” 
IRB Protocol: 20182089 
Sponsor: Altec Inc., Natick, MA 01760 
Funding: SBIR Phase II (NIH/NIDCD) ; Application # R44DC017097 
PI: Gianluca De Luca 
Background  
This newly funded NIH Phase II SBIR research study will continue our development of subvocal speech 
recognition, which represents a cutting-edge technology with the potential to be used for a large variety 
of augmentative and alternative communication (AAC) applications. Unlike natural speech, subvocal 
(silently mouthed) speech is not dependent on acoustic interactions and thus is not susceptible to 
environmental noise corruption. More importantly, subvocal speech has the potential to provide a new 
and effective form of communication to those who have undergone laryngectomy and lost the ability to 
vocalize.  
Recent studies of ours have demonstrated that surface electromyographic (sEMG) signals recorded 
from muscles of the face and neck can be reliably translated to text and synthesized into speech using a 
personalized, prosodic digital voice. When tested on a 2,500-word vocabulary of continuous phrases 
among participants with laryngectomy, we succeeded in translating subvocal speech-to-text with a 90%-
word recognition rate. Taking these developments a step further in our Phase I SBIR, we demonstrated 
that it is possible to capture phrase-level differences in stress (realized via altered pitch, loudness, and/or 
duration) from the sEMG signals as well as synthesize natural, word-level variations in intonation and 
timing through a digital voice that is personalized to each individual. When tested among participants with 
laryngectomy, we observed clear improvements in speech intelligibility, acceptability, and stress 
discriminability over electrolaryngeal speech aid alternatives. 
What Advancements are Provided by This Project? 
Leveraging our prior advancements for sEMG-to-
speech synthesis, we propose to develop the 
MyoVoice™: a new sEMG voice restoration system that 
translates silently mouthed words and phrases into 
prosodic vocal output; i.e. digitized speech that 
includes intonation, emphasis, and rhythm to convey 
meaning that is personalized to the users original 
voice(see Figure 1). This innovation will also have broad 
impact among millions of AAC users by restoring not 
only the vocabulary, but also the prosodic attributes of 
speech within a personalized digitized voice.  
Justification for Study 
This project is prompted by the need for more effective, practical, and user-friendly AAC devices for 
persons unable to communicate effectively through vocalization. Because sEMG-based speech 
recognition does not rely on acoustic excitation of the vocal tract, it is readily applicable to recognizing 
subvocal (i.e., silently mouthed) speech. Subvocal speech is therefore an obvious alternative form of 
communication for people with laryngectomy who still retain use of their speech articulator muscles but 
lack the ability to vocalize.  
 
Figure 1. Schematic of a proposed MyoVoice™ system for 
restoring vocal communication by transcribing sEMG 
signals detected from speech muscles while silently 
mouthing words. The translation is re-interpreted as a 
personalized and prosodic digitized voice. 

Protocol Summary for R44DC017097 
 
 
 
 
 
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Specific Aims of Study 
In Aim 1, we translate our Phase I proof-of-concept phrase-level prosody recognition algorithms to 
ones that can transcribe within-phrase prosodic speech and track variations in prosody (pitch, loudness, 
and duration) to create linguistic boundaries, clarify lexical ambiguities, and convey emotional intent. To 
carry out this work, we acquired simultaneous acoustic and sEMG recordings as individuals with healthy 
voices speak a corpus of phrases comprising an extensive set of prosodic-phonemic combinations to 
elucidate the relationship between acoustic and sEMG representations of prosody. The data set was used 
to design new multi-level dynamic learning algorithms to identify person-specific variations in prosody 
based on a set of selected sEMG features. We also redesigned our Phase I subvocal speech algorithms 
that leverage the sEMG data to transcribe lexical content amidst the multitude of variations in pitch, 
loudness, and duration that exist in prosodic speech.  
In Aim 2, we advanced our Phase I sensor and algorithm development efforts for conversational use 
by developing software to manage interactions between the sEMG sensors and our speech algorithms 
developed in Phase I. The Aim 1 algorithms were trained on a reduced sensor subset, and subsequently 
achieved comparable algorithmic performance with a smaller number of sensors that will be incorporated 
into a newly designed custom-fit, reusable sensor veneer to facilitate non-expert sensor placement for 
repeatable algorithmic performance for the individuals with total laryngectomy.  
In Aim 3, the prototype MyoVoice™ system developed in Aims 1 and 2 was evaluated for social 
reception amongst persons with total laryngectomy and their primary speaking partner. Each participant 
evaluated the speech outputs from our sEMG-to-speech against the current gold-standard, electrolarynx. 
When evaluated for conversational efficacy, our MyoVoice™ system will be shown to yield greater 
preferences toward synthetic speech that integrates linguistic prosody based on fine-tuned estimates of 
pitch and loudness. The resulting pre-commercial AAC system will have broad-reaching impact for 
introducing a level of social interaction from an AAC device that is unprecedented among individuals living 
with articulatory-based vocal impairments. 
Upon the successful completion of this Phase II SBIR, we will deliver a prototype MyoVoice™ system 
complete with wearable, comfortable, user-accepted sensor and rapid mobile software that is cross-
platform compatible and capable of translating sEMG signals recorded from muscles of the face and neck 
into personalized, prosodic digital voice for restoring the natural conversational capabilities for individuals 
with vocal impairments. The innovation of the MyoVoice™ AAC device will have a broad-reaching impact 
for introducing a level of social interaction from an AAC device that is unprecedented among individuals 
whose articulator muscles remain intact yet lack the ability to vocalize effectively with a personalized, 
prosodic voice.  
Involvement of Human Subjects 
Human Subjects Involvement and Characteristics: Dr. Jennifer M. Vojtech, a Research Scientist at Altec, 
Inc., will coordinate the involvement of human subjects in the proposed project. She will work closely with 
the PI, Mr. Gianluca De Luca, and Secondary Study Coordinator, Dr. Serge H. Roy, to ensure that all aspects 
of human subject screening, enrollment, and testing complies with Federal regulations involving voluntary 
participation of human subjects in research, as determined by WCG IRB. 
 
Human subject involvement will consist of the voluntary participation of adults for data collection 
experiments described in the Research Strategy. These experiments are of two types:  
• 
Study 1(a): Collection of sensor and/or voice data during experiments in which subjects either 
read out loud and/or subvocally recite vowels by themselves, read text provided on a computer 
screen, and answer questions to elicit spontaneous speech; and  

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• 
Study 1(b): Listener experiments in which naïve control subjects listen to speech samples and 
make judgments about certain characteristics of the speech, such as how well they can correctly 
identify the vocabulary words (i.e., compute their word error rate) or distinguish between 
different speakers (i.e., evaluate personalization of digitized speech). The involvement of human 
subjects is described in greater detail for each experiment category: 
Study 1(a): Data collection for sEMG-based recognition and synthesis of prosodic speech  
General Description: This portion of the study is designed to create a data corpus to develop sEMG-based 
subvocal speech recognition and synthesis algorithms for prosodic speech in people with laryngectomy. 
The data collection will take place in the research facilities of Altec Inc. (23 Strathmore Rd, Natick, MA 
01760) under the supervision of the PI and the assistance of Dr. Jennifer Vojtech, Dr. Serge Roy, and other 
research team members. Testing will also involve Dr. James Heaton, a consultant expert on speech 
disorders with extensive experience in recording EMG signals from facial and neck muscles in control 
subjects as well as people with laryngectomy.  
The data collection will involve individuals with 
healthy voices. We will collect sEMG signals from key 
muscles of articulation from the face and neck (see 
Figure 2) while subjects are seated and asked to silently 
mouth vowels by themselves, read text that we provide 
to them on a computer screen, and answer questions 
we ask to elicit spontaneous speech. For experiments 
involving patients with laryngectomy, we will also 
acquire audio recordings of a subset of these phrases 
during either electrolaryngeal for comparison with 
subvocal speech. These alternative forms of speech are 
commonly used by people with laryngectomy and we 
therefore do not anticipate difficulty in finding subjects 
who are familiar with at least one, if not both, of these 
forms of speech production. Illustrations of these methods are provided in Figure 3. Electrolaryngeal 
speech is produced as an individual articulates their intended message while holding a hand-held 
electromechanical device (electrolarynx) against their neck to operate as an artificial larynx. 
Tracheoesophageal speech relies on a Tracheoesophageal Voice Prosthesis (TEP), which is a device made 
of medical grade silicone that is positioned between the trachea and the esophagus. The voice prosthesis 
itself does not produce a voice; instead it allows air to be delivered from the lungs into the esophagus 
where it is expelled through the mouth, resulting in a vibration of tissues in the lower pharynx, producing 
sound.  
For volunteers with healthy voices, 
the same phrase tokens will be vocalized 
while acoustic speech and sensor signals 
are recorded.  
All subjects will be video recorded 
during the experiments to help interpret 
the findings. These recordings will be 
destroyed at the end of the study. 
Study Site: The experimental data 
collections involving human subjects will take place in the research laboratory of Altec Inc. (23 Strathmore 
Rd, Natick, MA). The research laboratory and its equipment are adequate for implementing the 
 
Figure 2. Subject with laryngectomy operating the data 
acquisition system. One screen displays sEMG signals, the 
other displays sentence prompts.  
a) 
 
b) 
 
Figure 3. Subjects will use their a) electrolarynx and/or b) TEP for comparative 
purposes with our MyoVoice™ system. 

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experimental protocols. When necessary, we will also exercise the option of conducting the data 
collection procedure in the prospective subject’s home. This will be considered for instance when 
transportation is a problem. Our equipment is portable, and the protocol is of extremely low risk, so we 
do not see this accommodation as modifying the benefit/risk ratio.  
Data Acquisition Experiment: During the experiments, 
sensor data will be acquired from 4–8 wireless sEMG 
sensors from the face and neck (see Figures 2 and 4), and 
exercise the option of adding 2 more sensors to the 
forehead and one wireless inertial (IMU) sensor  to the 
chin to detect movement of the jaw or mouth. Sensor 
locations will be guided by previous EMG studies on pitch 
and volume modulation. A commercially available 
wireless data acquisition system designed for facial and 
other small-muscle applications (Delsys, Inc., Natick, MA) 
will be used to simultaneously record sEMG signals from 
the locations on the face and neck while the subject 
subvocalizes indicated stimuli (e.g., words or phrases; see 
Figure 4). A data acquisition graphical user interface (GUI) 
and infrastructure designed from previous studies will be used to implement the data corpus protocol in 
a manner that minimizes fatigue by allowing the subject to control the pacing of the sentences they read 
in a subvocal (silently mouthed) manner.  
Text prompts to the subject will be derived from a subset of a 2,500-word corpus that was previously used 
for building subvocal speech recognition models. Phrases will be selected to include a minimal set of 
training vocabulary with comprehensive phoneme-prosody combinations.  
For the experiments involving individuals with healthy voices, the subjects will vocally speak the phrases 
while their voice is recorded by a microphone and sEMG signals are recorded from articulator muscles of 
the face and neck. These data will be used for developing sEMG-based algorithms for recognizing 
segmental and prosodic content of subvocal speech as well as for advancing sEMG voice synthesis engines 
for digitizing a personalized, intelligible, and expressive digital voice. 
Sensor Placement: The skin area of each sensor location will first be prepared using a disposable shaver 
(if needed to remove facial hair), alcohol wipe, and several tape peels to exfoliate the site. The ventral 
neck sensor pairs will be placed in submental (#1, 2) and ventromedial (#3, 4) regions, and the face sensors 
will be placed over supralabial (#5, 6) and infralabial (#7, 8) regions (see Figures 2 and 4). Two additional 
sensors will be placed on the forehead to measure contraction of eyebrow elevating muscles (frontalis) 
and eyebrow furrowing muscles (corrugator supercilii), respectively. A double-sided hypoallergenic 
adhesive tape with cutouts for the electrode contacts with skin will be used to secure the sensors to the 
skin. This unilateral sensor placement allows for audio recordings using an electrolarynx on the 
contralateral side.  
Subject Population: Although laryngectomy is much more prevalent in males than females (4:1; American 
Cancer Society, 2001), it affects both sexes. We will make every effort to include both males and females. 
Subjects must be proficient in English so that we can accurately associate muscle activation patterns to 
intended speech characteristics, as well as literate in English so that they can read speech task prompts 
from a computer monitor. Children will be excluded from participation as laryngectomy is extremely rare 
in this population.  
 
Figure 4. Surface EMG data will be recorded using 
commercially available Delsys, Inc. sEMG sensors. 

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Recruitment Process: Persons with total laryngectomy will be recruited through referrals from Dr. James 
Heaton, a consultant from the MGH-Center for Laryngeal Surgery & Voice Rehabilitation in Boston, MA. 
Our group has been collaborating with Dr. Heaton for the past 8 years during the early stages of 
developing subvocal speech capabilities. The Center maintains a sizeable database of clients with 
laryngectomy who have expressed their interest in participating in research studies and Dr. Heaton will 
be available to guide us in the selection and screening process. Dr. Heaton is also directly involved in local 
Laryngectomy support groups in New England and will have access to additional candidates. Control 
subjects will be recruited by word of mouth. The relatively small recruitment goal is not expected to 
necessitate postings, advertisements, or flyers.  
Potential Risks/Minimizing Risks: Subjects will be exposed to no more than minimal risk as a result of 
their participation. Whenever electrical devices make contact with the body, there is always a risk of 
electric shock. This risk is minimized because the sEMG sensors and IMU sensors are wireless, low-voltage 
devices (i.e., no cabling connected to mains) and therefore are completely isolated from electrical sources. 
The sensors are also commercially available (TrignoTM Mini; Delsys, Inc.) and comply with U.S. and 
internationally recognized medical device standards as well as FDA oversight.  
For persons with fragile skin, there is a risk of irritation or breakdown of the skin from the placement 
of sensors on the skin. The risk is equivalent to wearing a Band-Aid for several hours and peeling it off. 
This risk will be minimized by wiping the skin using an alcohol prep pad and securing the sensors using 
interface materials that are hypoallergenic or of medical grade (such as adhesive backings or hydrogels) 
and approved for medical use on the skin. We will also screen the subjects and exclude subjects with skin 
lesions or a history of frequent skin breakdown from bandages.  
Areas near the stoma or approximating scarring or tissue sensitivity due to surgery or radiation will 
be avoided. Dr. James Heaton will be present during these data acquisition experiments and has extensive 
clinical experience in supervising such recordings. The skin will be inspected following removal of the 
sensors. We will have over-the-counter skin moisturizer available to alleviate any dryness to the skin that 
may result.  
Because recording procedures are anticipated to last on average 4–5 hours, there is possibility of 
subjects feeling tired or bored during the recording session. Providing rest periods of at least 5 minutes 
per half hour will help alleviate such discomforts and maintain subject attention. Subjects will be free to 
stand up and walk around and we will provide light snacks, a lunch (if during mid-day), and beverages. If 
the subject appears to be getting tired despite these efforts and cannot attend to the task, we will ask 
them to return on another day to complete the study. 
Due to the ongoing COVID-19 pandemic, subjects may increase their risk of exposure to COVID-19 by 
coming into Altec, Inc. and interacting with other people. COVID-19 is an infectious disease that is easily 
transmitted by air and can pose a serious health threat to some people. We will ensure that proper CDC 
and Massachusetts state regulations and guidelines are followed to minimize risk of COVID-19 
transmission during the study. 
 
Study 1(b): Listening experiments to evaluate recognition of synthesized voices 
This portion of the study will be limited to n=10 subjects with healthy voices. Subjects must speak and be 
literate in English so that they can understand instructions, as well comprehend speech recordings that 
will be presented to them in English. We will seek recruits with no clinical experience with laryngectomees. 
Listeners must also be comfortable in typing phrases into a computer using a keyboard and mouse. Both 
males and females will be included in equal numbers so that possible sex-specific differences can be 
accommodated for men and women during the experiments. We will exclude candidates with conditions 
which might disqualify them for participation – such as poor hearing, speech disorders, or memory 
disorders that are identified through an initial interview screening.  

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Description of Test Procedures: The experiments will take place in the research facilities of Altec Inc. under 
the supervision of the PI and the assistance of Dr. Jennifer Vojtech and Dr. Serge Roy. Listening 
experiments will require 1–2 hours. Study participants will first undergo a brief hearing screening at 1000, 
2000, and 4000 Hz randomly to each ear at 25dB through the headphones of an audiometer (Maico 
Diagnostics MA-27). Any participant who is unable to hear any of the three tones in both ears will have 
failed the screening test and will be compensated for their time/transportation and dismissed. After the 
hearing screening, subjects will be seated at a computer workstation in a quiet office setting. They will be 
instructed to listen to a series of short phrases through speakers or headphones that are like the phrases 
in Experiment 1(a). Subjects will be prompted at the completion of each phrase to make judgments about 
certain characteristics of the speech, including the acceptability of the speaker’s voice, the identity of the 
speaker, and the emotion conveyed within the message. The criteria on which to judge acceptability will 
be based on acceptability instructions advocated by Bennett and Weinberg44 which includes the speaker's 
fluency, rate, inflection, and “pleasant” quality. Subjects will also be instructed to orthographically 
transcribe the phrase they heard (i.e., to assess intelligibility) and answer a question about the phrase 
(i.e., to assess comprehensibility). Answers will be entered by the subject using a keyboard and mouse in 
a field visible on the screen below the prompt. The subject will be able to control when a new prompt 
appears and can interrupt the testing at any time to rest or ask a question. There will be no sensor 
recordings in this experiment or any instrumentation other than the computer and acoustic stimuli. 
Recruitment: Same as described for control subjects in Experiment 1(a) 
Potential Risks/Minimizing Risks: The primary risk/discomfort will be boredom or fatigue associated with 
the relatively long duration of the experiment. We will provide the same mitigating activities (rest, 
refreshments, etc.) as in Experiment 1(a) description. No risks associated with the use of sensors are a 
factor in this portion of the study.  
GENERAL INFORMATION FOR BOTH STUDIES 
Informed Consent: A single consent form will be used for Study 1(a) and 1(b). All persons will be properly 
informed of the purpose of the study by members of the research team and will have the opportunity to 
read the informed consent outlining the experimental procedures and review their rights as a human 
subject. Dr. Heaton will make the first contact with the prospective laryngectomy subjects to explain the 
involvement of human subjects in the study and answer any questions. Dr. Heaton will provide a copy of 
the informed consent form to the subject as a written description of the study which they will not sign 
until they have had the opportunity to visit Altec Inc. and meet with Drs. Vojtech and Roy, who will 
demonstrate the various equipment and review once more the nature and details of the study. Dr. 
Vojtech, Dr. Roy, or Mr. Gianluca De Luca (PI on the study) will be administering consent. Control subjects 
will be sent a copy of the informed consent form to review before deciding whether they wish to 
volunteer. The consent form will be administered upon arrival to Altec, Inc. after answering any questions 
and demonstrating the protocol. All subjects should be competent to give informed consent.  
A signed and dated copy of the consent form will be provided to each subject, with the signature of 
the person obtaining consent. Identifiers linking the subject to their participation in the study will be kept 
in a locked cabinet accessible by the PI. Each of the researchers on this project is familiar with the 
appropriate Federal guidelines regarding the use of human subjects for research, and certificates of 
compliance required by the NIH are on file.  
 
Confidentiality: It will be difficult to completely de-identify the data collected in Study 1(a) because there 
will be voice and videotaped recordings in addition to the sEMG recordings. For this reason, data will be 
stored on a password-protected PC computer with limited local accessibility and a high-security firewall 
preventing file access from external locations. All data will be backed-up, encrypted and password-

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protected on external drives. Confidentiality will be assured by relying on a subject identification coding 
system. No references to the subject name or other identifiers (initials, address, license number, date of 
birth, etc.) will ever appear in publicly accessible documents or publications. The subjects’ test results will 
only be made available to the subject and the researchers directly involved in the study. Since these 
experiments do not involve medical testing, these results will not become part of the subjects’ medical 
record. The video/voice data will be kept in storage during the study and destroyed once completed.  
 
Importance of Knowledge and Potential Benefits: The study is intended to provide an AAC technology 
that translates silent mouthed words and phrases directly into synthesized prosodic and personalized 
voice for those with vocal impairments. The potential benefits to society are high in terms of developing 
an EMG voice restoration system that restores not only vocabulary, but also the prosodic attributes of 
speech using an emerging personalized voice synthesis technology. The technology will be packaged into 
a wearable sensor system that provides natural embodiment, cosmetic appeal, and intuitive vocal 
capabilities not otherwise possible. 
 
Potential Benefits to the Subjects: There are no anticipated benefits for subjects in this study aside from 
the potential benefits society may experience if our results lead to new EMG voice restoration technology.  
 
Alternatives to Participation: This study does not involve medical diagnostics or treatments for which 
alternatives can be offered. 
 
Costs to the Subject: Subjects will not incur costs for their participation.  
 
Compensation for Participation: Subjects will receive compensation for travel expenses if they need to 
take public transportation or taxi. No parking expenses are anticipated as we have our own free parking 
lot. Individuals who come to our facility but fail to meet enrollment criteria will receive $25 remuneration 
for their travel time and effort. Subjects who complete the 4-5 hour recording protocol will receive 
$25/hour, and subjects completing only part of the protocol (due to their choice or technical difficulties 
on our part) will receive payment of $25/hour for their time spent. A private car transportation service 
door-to-door will be available at no cost to subjects that do not have other means of transportation.