18. GOALSFORFELLOWSHITPRAININGANDCAREER My goal is a career as a research scientist studying the functional anatomy of the nervous system, with particular emphasis on the application of knowledge to human disease. Under Dr. Ryugo' s supervision, I will have the opportunity to learn both anatomical and physiological methods for the study of the nervous system. I have found Dr. Ryugo's laboratory to be a collegial and intellectually stimulating environment. Dr. Ryugo is consistently available to discuss ideas, literature, and results. The laboratory is located within the Center for Hearing Sciences, which provides a diverse community of scientists interested in the auditory system. During the fellowship, I plan to take several courses in the Neuroscience Department to learn more about the auditory system and synaptic plasticity. I also intend to assistant teach in at least one more undergraduate neuroscience course, which will improve my speaking and teaching skills. SPONSOR 19. NAMEANDEGREE(S) David K. Ryug% PhD 20. POSITION/RANK Professor of OtolaryngoloNg-HNS and Professor of Neuroscience 21,RESEARCHINTERESTS/AREAS Functional anatomy of the auditory nerve and the central auditory system. REI _EARCH PROPOSAL 22. DESCRIPTION (Do not exceed space provided) Sound-evoked activity plays a critical role in the development of the auditory system. Likewise, auditory deprivation resulting from deafness causes abnormal development at many levels. Previous work has shown that congenitally deaf animals, including the deaf white cat (DWC), have morphologic abnormalities at the endbulb of Held synapse, an important central synapse of the auditory nerve. The proposed research will explore the functional implications of these morphologic abnormalities, the sensitivity of the synapse to deafening at various ages, and the extent to which the changes can be prevented or reversed by artificial stimulation of the auditory nerve with a cochlear implant. The long-term goal is to define a critical period during which the auditory system is sensitive to deafness. It has long been known that postlingually deafened adults, and deaf infants implanted early, receive more benefit from cochlear implantation than congenitally deaf individuals implanted as adults. The abnormalities seen at the endbulb synapses in deaf mammals may cause abnormal activity in higher auditory centers, and could explain the difficulties deaf adults have in interpreting auditory nerve stimulation. Thus, the proposed studies are not only relevant to general neurobiological issues of auditory plasticity and development, but also to mechanisms of rehabilitation in deaf humans. PHS 416-1 (Rev. 12/98) Page 2 cc NAME (Last, first, middle initial) Individual NRSA Application Table of Contents ========================================Section End===========================================
| Ryugo, D K; Kretzmer, E A; Niparko, J K (2005) Restoration of auditory nerve synapses in cats by cochlear implants. Science 310:1490-2 |
| Kretzmer, Erika A; Meltzer, Noah E; Haenggeli, Charles-Andre et al. (2004) An animal model for cochlear implants. Arch Otolaryngol Head Neck Surg 130:499-508 |
