The long-range goal of our laboratory is to understand how cortical, tectal, cerebellar and basal ganglionic circuits interact to initiate and shape motor behavior. We believe a deep understanding will require the ability to transcend the different levels of experimental analysis from the firing behavior in single neurons through the patterned activity occuring within large-scale neuronal populations in different brain regions to finally a rigorous analysis of the behavior itself.

To this end, our research combines intracellular microlectrode recording, high-speed voltage-sensitive dye (VSD) imaging, large-scale computational modeling and kinematic analysis of behavior. We have selected the freshwater turtle, Pseudemys scripta, as our animal model since its central nervous system is especially amenable to experimental analysis. The image at the right shows a living isolated turtle brain with the eyes attached. In normal physiological saline, this in vitro preparation responds well to visual stimulation for up to 3 days. Moreover, the visual cortex (CTX), optic tectum (OT) and the cerebellar cortex (CB) have smooth, unfolded surfaces that are ideal for combined intracellular recording and VSD imaging. The behavior we are focusing on is the capture of fish which not only requires the turtle to track the prey's current location but also to extrapolate its future location in order to correctly aim its attack. We believe the turtle solves this motion extrapolation problem through the interaction of cortical and tectal neural circuits mediated via the basal ganglion with important contributions from the cerebellum. Click on research to read more.