"Caudated-induced" cortical potentials: comparison between monkey and cat.

The segment of the internal capsule which carries axons relating to the sensorimotor cortex does not closely adjoin the caudate in the monkey as it does in the cat. Therefore, in seeking evidence for caudate-induced cortical responses, activation of the adjoining internal capsule by stimulus spread can be avoided. In the monkey, caudate stimulation never produced cortical responses, and only capsule stimulation evoked the potential complex which has been attributed to caudate stimulation in the cat.