Associate Professor (Hearing Sciences)
Phone: 812 856 1069
B.S. Biology, 1974 Indiana University (Northwest Campus)
M.S. Physiology, 1979 University of Illinois at Urbana-Champaign
Ph.D. Physiology, 1983 University of Illinois at Urbana-Champaign
Postdoctoral Fellow, 1983-85 Dept. of Biomedical Engineering, John Hopkins University School of Medicine
Perception is a biological process. The sensations and perceptions associated with any sensory system arise through a series of neurobiological events. The process begins in the periphery with the transduction of the physical stimulus into neural impulses and ultimately ends with the recognition of the stimulus by the organism. I am interested in understanding how the physical features of complex sounds are encoded or represented in the auditory nervous system and how these representations are then related to the perceptual attributes of the sound.
To address these issues, my research program is directed along three lines of investigation.
- Conduct psychophysical experiments in human listeners to define the perceptual attributes and detection/discrimination thresholds for a set of complex sounds. How does behavioral performance or perception change as a specific acoustic feature changes systematically?
- Conduct similar psychophysical experiments using operant-conditioning in chinchillas to the same types of sounds. Again, how does behavioral performance change as a specific acoustic feature changes systematically? What are the perceptual differences and similarities between humans and chinchillas?
- Record the activity of single neurons in the chinchilla auditory system in response to the same types of complex sounds. How do the neural representations encoded in firing rate and temporal discharge patterns change as a specific acoustic feature changes systematically?
Withnell, R.H., Jeng, P.S., Shofner, W.P., Allen, J.B. (2010) In-situ calibrated sounds and hearing sensitivity. Proceedings of Meetings on Acoustics, Vol 9(1), 10 pages.
Yost WA, Shofner WP. (2009) Critical bands and critical ratios in animal psychoacoustics: an example using chinchilla data. Journal of the Acoustical Society of America 125: 315-23.
Shofner, W.P. (2008) Representation of the spectral dominance region of pitch in the temporal discharge patterns of cochlear nucleus units. Journal of the Acoustical Society of America 124: 3038-52.
Shofner, W.P., Yost, W.A. and Whitmer, W.M. (2007) Pitch perception in chinchillas: Stimulus generalization using rippled noise. Journal of Comparative Psychology. 121: 428-439.