The Neural Coding Group is part of the Eaton-Peabody Laboratories at the Massachusetts Eye and Ear Infirmary. Members of the lab are also affiliated with the Harvard-MIT Program in Speech and Hearing Bioscience and Technology and the Department of Otology and Laryngology at the Harvard Medical School.
Spatio-temporal response pattern of the auditory nerve to a harmonic complex sound.
The long-term goal of the group's research is to determine how speech and other biologically-significant sounds are processed by the auditory system, with a focus on understanding the neural mechanisms underlying auditory perception. To achieve this goal, we combine three major techniques of integrative neuroscience: neurophysiological (single-unit recordings), computational (mathematical models) and behavioral (perceptual experiments). Currently, efforts are focused in two major directions: (1) studies of the neural mechanisms of binaural and spatial hearing in the auditory brainstem, with particular emphasis on everyday, challenging acoustic environments that include multiple sources and reverberation, (2) studies aimed at improving processing strategies in cochlear implants, particularly bilateral implants. In the latter studies, we are especially interested in the consequences of early-onset deafness on binaural processing by central auditory neurons and whether the resulting abnormalities can be reversed by appropriate stimulation though cochlear implants.
These lines of research are related in that, while normal-hearing listeners excel at understanding speech in noisy and reverberant environments, hearing-impaired and cochlear-implant patients often have difficulties in these adverse environments, even if they do well when facing a single speaker in a quiet room. Similar difficulties processing speech in adverse environments are also encountered by artificial systems for speech transmission and recognition. To understand these differences between normal listeners on the one hand, and hearing impaired listeners and artificial systems on the other hand will require an integrated knowledge of the auditory processing of speech, binaural processing in the auditory brainstem, and how these mechanisms are altered by pathology, especially when it occurs early in life. Such knowledge will be invaluable for a rational design of improved hearing aids and auditory implants.
|Neural coding of pitch and music|
|Neural correlates of binaural and spatial hearing|
|Physiology of cochlear implants|
|Perception and neural coding of temporal envelope|
|Neural representation of speech|
|Computational models of auditory neurons|
|Physiological basis of masking and frequency selectivity|
Recent Poster Presentations
Comments to Bertrand_Delgutte at meei.harvard.edu