John H. Grose, PhD, is the Principal Investigator on an NIH-funded project that examines complex sound processing in normal and impaired auditory systems. This project was competitively renewed in September, 2008, with a focus on the role of temporal processing in perceptual organization. In particular, a major emphasis is on understanding the decline in temporal processing with age. Current work, presented at the 2009 Midwinter meeting of the Association for Research in Otolaryngology, indicates that deficits in envelope processing are present in older listeners but only for high modulation rates, not low rates. This, in turn, has invited investigation into the reduced benefits that older listeners exhibit for speech perception in low modulation rate noise. A second set of experiments has focused on fine structure coding as measured by inter-aural time difference thresholds. As expected, older listeners perform more poorly than younger listeners, but of greater interest is that this deficit is evident even in the pre-senescent (middle-aged) auditory system. This work was presented at the Spring 2009 meeting of the Acoustical Society of America. A major effort at the moment is to expand this work to include electrophysiological measures of temporal processing.
In addition to his major research emphasis, Dr. Grose is active clinically in the evoked potential testing of infants and toddlers, as well as patients with cochlear implants.