Identification of Cortical Cells Projecting to the Dorsal Column Nuclei of the Cat

Neurones projecting from cerebral cortex to dorsal column nuclei in the cat were identified by stimulating their axons in these nuclei and recording antidromic responses of individual cell‐bodies in the cortex. Latencies of response for 42 such neurones gave conduction velocities between about 3 and 20 m./sec. Corticogracile neurones were found medially and corticocuneate neurones laterally in the sensorimotor region; and histological identification of recording sites for 24 cells showed that most lay in area 3a. Hair‐sensitive skin receptive fields were found for 2 cells, and less well‐defined skin excitation for 5 others: the skin area corresponded to the region served by the nucleus to which the individual cell projected. Ten corticonuclear cells tested were shown to be independent of the corticospinal tract.