Connecting the Two Sides of the Brain: Cortical Topography and its Growth Cones


April 9, 2014 - 1:00pm
NW 243
About the Speaker
Alex Poulopoulos (Macklis Lab)

Brain circuits in mammals display staggering complexity, with vast networks of long-range connections between neurons across and within sensory, motor, and associative systems. Despite their multitude and diversity, a consistent feature underlying many long-range connections is their adherence to topographic organization. This feature appears throughout the central nervous system, manifesting in the retinotopic maps of the visual system, the tonotopic maps of the auditory system, somatotopy in body sensation, myotopic maps in motor systems, and corticotopic connections across associative areas. To understand how topography forms in the developing brain, we studied the organization of the extensive corticotopic connections linking the left and right hemispheres of the mouse brain. We examined the mechanistic principles of this connectivity using transplantation experiments, and developed a method to isolate and analyze growth cones –the leading tips of growing axons– from specific neuron populations in an effort to identify the molecules that implement topographic organization in brain connectivity.