MoC3 Data and Model Reuse Abstract: Striatal correlates of locomotion

Our U19 group studies the functional and computational logic of connectivity between motor control centers and the spinal cord and muscle. We are anatomically and functionally characterizing the role of projection-specific populations of corticospinal neurons during particular modes of motor control based on cell-type specific connectivity between brain and spinal cord and employing novel imaging and electrophysiological techniques to measure and manipulate functionally and genetically-defined neural populations, and state-of-the-art computational tools. Because even the simplest motor program requires the activation of many neuronal populations across multiple brain areas, we are investigating the contribution of cortical and subcortical areas to the spinal cord and to muscle activity. We aim to dissect the contributions of activity in specific neural populations using closed-loop optogenetic manipulations and implement a dynamic back and forth between anatomical and functional mapping experiments, computational and conceptual models, and causal testing of predictions.

Previous work from our lab and others indicates that direct and indirect striatal projection pathways are concurrently active during movement initiation, this activity is action-specific, and needed for proper movement. However, this work was done by measuring activity in each pathway independently. As part of optimizing several imaging parameters, we have collected calcium imaging of striatal projection neurons during spontaneous locomotion in the mouse:

• Dual-color 2-photon imaging of both direct- and indirect-pathway neurons from dorsolateral striatum             
• Spontaneous locomotion on a running wheel with encoder for speed output
• Simultaneous video of mouse on the wheel

These data are amenable for the application of computational models to help determine the neural dynamics and relation between neurons of both pathways during spontaneous locomotion.