Thalamic projections from the precentral motor cortex in Macaca fascicularis.

Radioactive amino acids were injected into area 4 in 7 monkeys (Macaca fascicularis). Ipsilateral corticothalamic projections were traced to Olszewski's nucleus ventralis lateralis pars oralis and pars medialis, the nucleus ventralis posterior lateralis pars oralis, the nucleus ventralis posterior medialis and inferior and to the nucleus reticularis. Some fibers appeared to terminate in the ipsilateral nucleus ventralis lateralis pars caudalis, the nucleus lateralis posterior and the nucleus subthalamicus.