|Donald M. Caspary, Ph.D.
Professor, Distinguished Scholar
|Auditory Neuropharmacology: Age-related hearing loss (presbycusis) is a complex state which may reflect pathological influences along the entire auditory system. For certain kinds of age-related hearing loss, there is a dramatic loss of speech understanding without a parallel loss in pure-tone thresholds. This loss is especially severe under noisy conditions. Central auditory dysfunction in aging may be in response to partial peripheral deafferentation and may be similar to changes observed with noise exposure or ototoxic drugs. In many ways, the underlying causes of tinnitus, the hearing of phantom sounds, may also reflect changes due to the partial deafferentation of the central auditory processor. These changes may involve changes in the synthesis, degradation, uptake, release and receptor sensitivity of neurotransmitter systems. Studies in our laboratory are focused on the understanding of two closely related questions in auditory research:
Recent Honors and Awards
Llano, D.A., Turner, J.G., Caspary, D.M.: Diminished Thalamocortical Inhibition in an Aging Mouse model of Chronic Tinnitus., J Neurosci. 2012 Nov 14;32(46):16141-8. PMID:23152598
Caspary, D.M., L.F. Hughes, L.L. Ling: Age-Related GABAA Subunit Changes in Rat Primary Auditory Cortex. Neurobiol Aging. 34 (2013), pp. 1486-1496 DOI information: 10.1016/j.neurobiolaging.2012.11.009
Richardson BD, Ling LL, Uteshev VV, Caspary DM. Reduced GABAA receptor-mediated tonic inhibition in aged rat auditory thalamus. J Neurosci. 2013 Jan 16;33(3):1218-27a. PMCID: PMC3717293.
Richardson BD, Hancock KE, Caspary DM. Stimulus-specific adaptation in auditory thalamus of young and aged awake rats. J Neurophysiol. 2013 Oct;110(8):1892-902. Epub 2013 Jul 31. PMCID: PMC3798939.
Duque D, Malmierca MS, Caspary DM. Modulation of stimulus-specific adaptation by GABAA receptor activation or blockade in the medial geniculate body of the anaesthetized rat. J Physiol. 2014 Feb 15;592(Pt 4):729-43. Epub 2013 Oct 7. PMCID: PMC3934711.
Cai, R., B.I. Kalappa, T.J. Brozoski, L.L. Lynne, D.M. Caspary. GABA Neurotransmission Enhanced in Auditory Thalamus Relative to Inferior Colliculus? J Neurophysiol. 2014 Jan;111(2):229-38. doi: 10.1152/jn.00556.2013. Epub 2013 Oct 23. PMID: 24155003
Henry, J.A., L.E. Roberts, D.M. Caspary, S.M. Theodoroff, R.J. Salvi. Underlying Mechanisms of Tinnitus: Review and Clinical Implications. J Am Acad Audiol. 2014 Jan;25(1):5-22; quiz 126. doi: 10.3766/jaaa.25.1.2. PMID: 24622858
Kalappa B.I., T.J.Brozoski, J.G. Turner, D.M. Caspary. Single-unit hyperactivity and bursting in the auditory thalamus of awake rats directly correlates with behavioral evidence of tinnitus. J Physiol. 2014 Nov 15;592 (Pt 22):5065-78. doi: 10.1113/jphysiol.2014.278572. Epub 2014 Sep 12. PMID:25217380
Recent Invited Presentations