About half of the patients who undergo total laryngectomy to treat advanced laryngeal cancer rely on a handheld artificial electrolarynx (EL) for communication. Unfortunately, the need to use one hand to control an EL is physically limiting, and these devices produce speech that sounds non-human, has reduced intelligibility and loudness, and draws undesirable attention to the user. The primary aim of this project is to develop an improved artificial electrolarynx communication system that more closely approximates normal voice and speech production. This will be accomplished in laryngectomy patients by developing a neural interface to provide hands-free control of an improved EL sound source, i.e., a voice neural prosthesis. We will carry out a prospective surgical protocol to preserve phonation-related signals from both normally innervated strap muscles and from strap muscles that have been reinnervated by the recurrent laryngeal nerve. The signals will be detected using surface EMG electrodes and will be processed by a DSP-based system that will control a linear, hands-free EL transducer to produce more human-sounding speech. Patients will be systematically followed post-laryngectomy using electrophysiological and imaging approaches to better understand how underlying anatomical and physiological factors influence the development of neural prosthetic voice. Laryngeal nerve morphology will be studied in surgical specimens to help interpret recovered EMG signals. A post-surgical training protocol will be employed to ensure development of maximum proficiency with the new system, and to formally assess the role of training in the use of a voice neural prosthesis. A main goal is to formally compare speech communication using the two different innervation sources and conventional manual control. In addition, an ongoing iterative development effort will also attempt to use more advanced signal processing approaches to further improve/optimize the degree to which system performance approximates normal speech production in individual patients. In the long-term, once the fundamental approaches have been established, we plan to utilize aspects of this new technology for a broader laryngectomy population, and as a foundation for future efforts to develop additional surgical-prosthetic/neuroprosthetic approaches to voice and speech rehabilitation. ? ?
Stepp, Cara E; Heaton, James T; Rolland, Rebecca G et al. (2009) Neck and face surface electromyography for prosthetic voice control after total laryngectomy. IEEE Trans Neural Syst Rehabil Eng 17:146-55 |
Kubert, Heather L; Stepp, Cara E; Zeitels, Steven M et al. (2009) Electromyographic control of a hands-free electrolarynx using neck strap muscles. J Commun Disord 42:211-25 |
Saikachi, Yoko; Stevens, Kenneth N; Hillman, Robert E (2009) Development and perceptual evaluation of amplitude-based F0 control in electrolarynx speech. J Speech Lang Hear Res 52:1360-9 |
Stepp, Cara E; Heaton, James T; Hillman, Robert E (2008) Post-laryngectomy speech respiration patterns. Ann Otol Rhinol Laryngol 117:557-63 |
Goldstein, Ehab A; Heaton, James T; Stepp, Cara E et al. (2007) Training effects on speech production using a hands-free electromyographically controlled electrolarynx. J Speech Lang Hear Res 50:335-51 |