Characteristics of projections from primary sensory cortex to motorsensory cortex in cats

Abstract

The detailed organization of projections from sensorimotor cortex (Sml) to motorsensory cortex (MsI) was examined utilizing intracortical microstimulation (ICMS) in cats. The area of SmI projecting to near the lateral end of the cruciate sulcus lay near the lateral end of the postcruciate dimple. The low threshold region within the depths of SmI for exciting a given cell of MsI by ICMS was extremely restricted in the vertical direction. Comparison of peripheral receptive fields of cells in the interrelated regions of the two cortical areas shows that the two regions receive input from overlapping or contiguous peripheral loci. Blocking transmission through SmI by local cooling of SmI cortex failed to show a significant effect on the peripheral activation of cells in MsI. This suggests that this pathway is not a simple relay for transmission of sensory information to MsI. © 1970.