Principles of sensorimotor cortex connectivity

We use microelectrode mapping to parcellate somatosensory and motor cortical areas in squirrel monkeys. We then study the connectivity of individual sites with intracortical microstimulation + optical imaging. We apply this approach in hundreds of cortical sites to identify principles that govern sensorimotor cortex connectivity. Next, we rely on the connectivity map to guide microelectrode placement for the purpose of interrogating neural interactions that occur between connected zones. Thus, we use ICMS to drive activity in one zone while we simultaneously recording neural activity in a connected zone.

Our objective in this project is to determine the principles that govern the organization of intrinsic M1 connectivity. To achieve this goal, we study the spatial organization of M1 connectivity. Next, we interrogate the functional interactions between connected zones.

Spatial organization of M1 connectivity

Determining the spatial organization of M1 connectivity necessitates investigation at dozens of M1 sites. This scale of investigation cannot be practically achieved with anatomical tracers. Alternatively, we use intracortical microstimulation to drive neural activity at sites of interest while we optically image modulations intrinsic signal throughout M1 (illustrated above). Zones of activation report on the spatial location of neurons that were post-synaptically driven in response to ICMS.