Awake animals normally maintain a particular orientation with respect to gravity. This feature of behavior is so fundamental that it’s ingrained in our language: We refer to a failed business as going “belly up.” Posture is intimately dependent on signals from the inner ear, but we understand very little about how that information is mapped onto motor outputs. The Bagnall laboratory studies how sensory information about orientation and movement drives appropriate body movements to adjust posture.
To understand how animals maintain posture, we study the vestibulospinal system of the larval zebrafish. Vestibular neurons in the brainstem report an animal’s movement and orientation with respect to gravity. A subset of them project to the spinal cord. What happens to the signals they carry? The spinal cord is home to a wealth of neuron types, which we can visualize and manipulate easily with transgenic zebrafish lines. The lab is using a combination of electrophysiology, imaging, genetic manipulation, and behavioral analysis to identify how sensory signals about head orientation are mapped onto spinal circuitry to drive appropriate behaviors.
The laboratory is also interested in understanding how locomotor planning influences vestibular circuits. Many vestibular neurons receive direct input from the cerebellum, a motor planning structure. However, very little is known about the functional signals carried by the cerebellum. The lab takes advantage of the transparency of the larval zebrafish to watch cerebellar development dynamically over the critical period, and asks how it affects vestibular signaling during both quiescence and locomotion.
- Sengupta M, Daliparthi V, Roussel Y, Bui TV, Bagnall MW. Spinal V1 neurons inhibit motor targets locally and sensory targets distally. Current Biology. July 14, 2021; S0960-9822(21)00882-4. doi: 10.1016/j.cub.2021.06.053. Online ahead of print.
- Liu Z, Kimura Y, Higashijima SI, Hildebrand DGC, Morgan JL, Bagnall MW. Central vestibular tuning arises from patterned convergence of otolith afferents. Neuron. Nov 25, 2020; 108(4):748-762.e4.
- Callahan RA, Roberts R, Sengupta M, Kimura Y, Higashijima SI, Bagnall MW. Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control. Elife. Jul 29, 2019; 8:e47837.
- Roberts R, Elsner J, Bagnall MW. Delayed otolith development does not impair vestibular circuit formation in zebrafish. J Assoc Res Otolaryngol. Jun 2017; 18(3):415-425.
- Bagnall MW, McLean DL. Modular organization of axial microcircuits in zebrafish. Science. 2014; 343(6167):197-200.
- Bagnall MW, Hull C, Bushong EA, Ellisman MH, Scanziani M. Multiple clusters of release sites formed by individual thalamic afferents onto cortical interneurons ensure reliable transmission. Neuron. 2011; 71(1):180-94.
- McElvain LE, Bagnall MW, Sakatos A, du Lac S. Bidirectional plasticity gated by hyperpolarization controls the gain of postsynaptic firing responses at central vestibular nerve synapses. Neuron. 2010; 68(4):763-75.
- Bagnall MW, Zingg B, Sakatos A, Moghadam SH, Zeilhofer HU, du Lac S. Glycinergic projection neurons of the cerebellum. J Neurosci. 2009; 29(32):10104-10.
- Bagnall MW, McElvain LE, Faulstich M, du Lac S. Frequency-independent synaptic transmission supports a linear vestibular behavior. Neuron. 2008; 60(2): 343-52.
- Bagnall MW, Stevens RJ, du Lac S. Transgenic mouse lines subdivide medial vestibular nucleus neurons into discrete, neurochemically distinct populations. J Neurosci. 2007; 27(9): 2318-30.
See a complete list of publications on PubMed.
2002-2008 PhD, Neuroscience, University of California, San Diego
1996-2000 BS, Biology, Yale University, New Haven, CT
2017 McKnight Scholar Award
2016 Pew Scholar
2016 Sloan Award
2012 K99/R00 Pathway to Independence Award, National Institute on Deafness and Other Communication Disorders, NIH
2004-2007 National Science Foundation Graduate Research Fellowship