Three-dimensional topography of corticopontine projections from the rat sensorimotor cortex (S1, S2, M1)

3D reconstructed point coordinate data representing the spatial relationships of rat corticopontine projections originating from the primary somatosensory cortex (S1), the secondary somatosensory cortex (S2), and the primary motor cortex (M1). The corticopontine projections were anterogradely labeled following dual tracer injections into S1 and S2 or M1. The data demonstrate that whisker-related projections from S1 and M1 are largely segregated, but at some locations adjoining and partly overlapping. Furthermore, S1 contributes significantly more corticopontine projections than M1. Projections from corresponding representations in S1 and S2 terminate in similar parts of the pontine nuclei and display considerable amounts of spatial overlap.