EDUCATION:

    Ph.D. Expected: December, 2005, University of Maryland, College Park, MD
    M. S. in Experimental Psychology, 2000, Saint Joseph's University
    B. S. in Psychology, 1999, Saint Joseph's University 

RESEARCH INTERESTS

AUDITORY TEMPORAL PROCESSING IN BIRDS AND HUMANS:

    I have conducted several studies in birds and humans, in collaboration with Dr. Marjorie Leek and her lab at Walter Reed Army Medical Center.  We investigated the phase response of the avian basilar papilla using psychoacoustic methods in three species of birds (zebra finches, budgerigars, and canaries) and humans.  The birds showed a similar phase response across species, but showed significant differences in phase response compared to humans.   The differences are likely related to differences in the mechanics of the human and avian ears.  I next tested Belgian Waterslagers canaries (see below), a strain with a hereditary high frequency hearing loss related to hair cell abnormalities, using the same procedures and found that they differ markedly from normal-hearing canaries in that they show much less change in masking with changes in the phase spectra of the stimuli.  These results indicate that the phase response of the avian ear is severely disrupted with hair cell damage. 

    In a related project in collaboration with Dr. Leek and other members of her lab at Walter Reed Army Medical Center, we measured discrimination of temporal fine structure in humans with cochlear damage.  We found that hearing-impaired (HI) listeners were worse than normal-hearing listeners (NH) when tested at equal SPLs, but not at equal sensation levels, indicating that discrimination of changes in temporal fine structure are not severely reduced in HI listeners when audibility is taken into account .  Additionally, we found that randomly roving the presentation level of the stimuli significantly decreased discrimination performance in HI listeners, but not in NH listeners.

 

HEARING IN BELGIAN WATERSLAGER CANARIES:

    Belgian Waterslager canaries have a hereditary high frequency hearing loss associated with hair cell abnormalities (check out the Belgian Waterslager section of our webpage!).  We know a lot about the pathology underlying the hearing loss and vocalizations in these birds, but little is known about how the abnormal pathology affects hearing in these birds other than absolute thresholds.  I am investigating many aspects of sound perception in Belgian Waterslagers, such as frequency analysis, time analysis, intensity analysis, and perception of biologically relevant sounds.  These studies will help us reached a better understanding of the functioning of peripheral structures, as well as the integrated functioning of the entire auditory system in both normal-hearing and Belgian Waterslager canaries.  The results from these studies will also further develop this unique animal model in which we can look at the link between inner ear anatomy, auditory perception, and vocal learning.  Most animal models of hearing loss do not permit such an integrated view because they do not learn their vocalizations.

---

Return to the Laboratory of Comparative Psychoacoustics Home Page