Noel Cohen M.D. and Susan Waltzman Ph.D.'s investigations have focused on improving auditory function in the hearing impaired. The primary goal of a cochlear implant is to provide profoundly hearing impaired children and adults with sound and speech recognition not available to them with conventional hearing aids. The basic design of a cochlear implant system consists of an externally worn microphone, signal processor and transcutaneous transmitter and an implanted receiver stimulator and electrode array. The stimulation of the electrode array is dependent upon the strategy used to convert the incoming sound into electrical impulses.

The investigators have focused on two main areas: comparisons of implant systems and variables affecting postoperative performance of children and adults. Recent work has demonstrated that congenitally and prelingually deafened children obtain significant perceptual and linguistic benefit from implantation and that these benefits are further enhanced if implantation occurs between 2 and 3 years of age. Recently completed trials have included a prospective randomized study of several cochlear implant systems. Results revealed a superiority of multichannel systems over single channel devices and a significant difference between the two available multichannel implants in terms of word and sentence recognition.

Currently, they are involved in several clinical trials: the efficacy and safety of a new multichannel prosthesis and the benefits of an upgraded processor of an existing multichannel implant. Many technological advances in both electrode design and processing strategy are planned for the near future and they intend to continue our research with the new devices.

J. Thomas Roland, M.D.'s research interests have focused on ototoxicity of drugs and substances, medical therapy for Ménière's disease, and acoustic neuroma treatment.

Representative