Dr. Kuwabara's primary research interest has been in the functional organization of the mammalian central auditory system. Currently, his research is focused on the relationship between ascending and descending neural projections at the single cell level in various cell groups in the subcortical auditory pathways, such as inferior colliculus and superior olivary complex. Many of these cell groups are associated with binaural information processing for sound localization. For this study, he has been using intracellular labeling and recording techniques in brain slice preparations strategically combined with in vivo neural tract-tracing methods. He developed a unique, quasi-parasagittal brain slice preparation which can contain most of the auditory cell groups of one side of the brain--from thalamus to tectum to brainstem--with their neuronal connections largely intact. This preparation will add a powerful technical advantage to the current research. Morphological data are analyzed at the light and electron microscopic levels. He also has a research interest in comparative neuroanatomy of the central auditory system. Recently, he and a colleague in the department found a unique configuration of cell groups in the superior olivary complex of the vampire bat, a rare animal that echolocates with ultrasound, yet has excellent passive hearing at the audible sound frequency range. This comparative study will provide insight into a long-standing discussion on the common function of subdivisions within the lower brainstem auditory nuclear complex.
Kuwabara N., Zook J.M. (1999) Local collateral projections from the medial superior olive to the superior paraolivary nucleus in the gerbil. Brain Research, 846: 59-71.
Kuwabara N., Bhatnagar K.P. (1999) The superior olivary complex of the vampire bat, Desmodus rotundus (Chiroptera: Phyllostomidae). Acta Chiropterologica, 1: 81-92.
Kuwabara N., Zook J.M. (2000) Geniculo-collicular descending projections in the gerbil. Brain Research, 878: 79-87.
Bhatnagar K.P., Wagner C.E., Kuwabara N., Nettleton G.S., Campbell F.R. (2000) Right sided aorta: A cadaver report and brief discussion of human aortic arch anomalies. Annals of Anatomy, 182: 559-562.
Kuwabara N., Olson E.K. (2001) Intracellular and extracellular labeling of neurons in fresh slice preparations combined with multiple tract tracing. Biotechnic and Histochemistry, 76(4): 173-181.