Faculty & Research
- John Assad, Ph.D.
- Bruce P. Bean, Ph.D
- Azad Bonni, M.D., Ph.D.
- Richard T. Born, M.D.
- David Cardozo, Ph.D.
- David E. Clapham, M.D., Ph.D.
- Jonathan Cohen, Ph.D.
- David P. Corey, Ph.D.
- S. Robert Datta, M.D., Ph.D.
- Ruth Anne Eatock, Ph.D.
- Edwin J. Furshpan, Ph.D.
- Lisa V. Goodrich, Ph.D.
- Michael E. Greenberg, Ph.D.
- Chenghua Gu, D.V.M., Ph.D.
- Chris Harvey, Ph.D.
- David H. Hubel, M.D.
- Pascal S. Kaeser, M.D.
- Morris J. Karnovsky, M.B.B.CH., D.Sc.
- Joshua M. Kaplan, Ph.D
- Edward A. Kravitz, Ph.D.
- Margaret S. Livingstone, Ph.D.
- Qiufu Ma, Ph.D.
- Richard H. Masland, Ph.D.
- Joseph B. Martin, M.D., Ph.D.
- John H.R. Maunsell, Ph.D.
- David L. Paul, Ph.D.
- David D. Potter, Ph.D.
- Elio Raviola, M.D., Ph.D.
- Wade Regehr, Ph.D.
- R. Clay Reid, M.D., Ph.D.
- Bernardo Sabatini, M.D, Ph.D
- Thomas L. Schwarz, Ph.D.
- Rosalind Segal, M.D., Ph.D.
- Charles D. Stiles, Ph.D.
- Charles J. Weitz, M.D., Ph.D.
- Rachel I. Wilson , Ph.D.
- Clifford Woolf, M.D., Ph.D.
- Gary Yellen, Ph.D.
Ruth Anne Eatock, Ph.D.
Associate Professor of Otology and Laryngology
Associate Professor of Neurobiology
http://www.masseyeandear.org/research/ent/eaton-peabody/epl-investigators/eatock/
Sensory signaling by hair cells and neurons in the inner ear
The receptor cells of the inner ear - called hair cells after their conspicuous bundles of fine specialized microvilli - transduce sound and head motions into electrical signals, which they transmit across synapses to afferent neurons, which in turn carry the electrical signals from the inner ear to the brain. We study all three stages (transduction, transmission and spike generation), typically in excised semi-intact preparations of rodent vestibular organs. The vestibular epithelia have a distinctive synapse between type I hair cells and primary afferent terminals: each hair cell releases glutamate-filled vesicles from many presynaptic ribbons onto a large calyceal ending of a primary afferent neuron. The figure shows voltage signals evoked in the calyx by sinusoidal deflections of the hair bundle. We investigate how the properties of specific ion channels shape the sensory signals. For example, both type I hair cells and calyces have large numbers of low-voltage-activated potassium channels. These channels may expand the frequency range over which vestibular reflexes compensate head motions (Eatock and Songer 2011) and make afferent spike timing irregular (Kalluri et al. 2010).
Recording the responses of a complex calyceal terminal to hair bundle deflections (sine burst, 2-100 Hz, bottom right)
Selected Publications:
Hurley KM, Gaboyard S, Zhong M, Price SD, Wooltorton JRA, Lysakowski A, Eatock RA (2006) M-like K+ currents in type I hair cells and calyx afferent endings of the developing rat utricle. J Neurosci 26:10253-10269.
Wooltorton JRA, Gaboyard S, Hurley KM, Price SD, Bao H, Garcia JL, Lysakowski A, Eatock RA (2007) Developmental changes in two voltage-dependent sodium currents in utricular hair cells. J Neurophysiol 97:1684-1704.
Kalluri R, Xue J, Eatock RA. (2010) Ion channels set spike timing regularity of mammalian vestibular afferent neurons. J Neurophysiol 104:2034-51.
Eatock RA, Songer JE (2011) Vestibular hair cells and afferents: Two channels for head motion signals. Annu Rev Neurosci 34:501-34
Lysakowski A, Gaboyard-Niay S, Calin-Jageman I, Chatlani S, Price SD, Eatock RA. Molecular microdomains in a sensory terminal, the vestibular calyx ending. J Neurosci in press.