LMU Division of Neurobiology
Department Biology II
Großhaderner Straße 2
+49 (89) 2180 - 74307
Fax: +49 (89) 2180 - 74304
Functional organization and developmental plasticity of extraocular motor function in Xenopus
Background. Compensatory eye movements are indispensable for image stabilization during self-motion. The necessary neuronal signals for this motor behavior are generated by a transformation of body motion-related visuo-vestibular sensory signals into appropriate extraocular motor commands for initiating spatio-temporally adequate eye movements. The short latency motor response is mediated by a three-neuronal reflex arc within the brainstem by sets of distinct cellular phenotypes.
Project. In the framework of the Amgen Scholars Undergraduate Summer Research Program, the scholar will conduct a combined morpho-physiological project in our laboratory that aims to elucidate the cellular mechanisms and ontogenetic plasticity of vestibular and visual sensory signal transformation for gaze stabilization in larval Xenopus laevis.
Methods. Using neuronal tract tracing with fluorescent tracers combined with extracellular recordings of single fibers and multiple-units of the various oculomotor nerves together with non-invasive video-imaging of eye motion in semi-intact in vitro Xenopus tadpole preparation, the scholar will reveal the functional organization of the extraocular motor commands during several tasks of sensory stimulation and interactions. The use of different developmental stages of larval Xenopus laevis allows determining the cellular plasticity that is necessary to dynamically adapt the motor output to the range of locomotor capability.