Reconstructions of corticogeniculate axons in the cat.

The terminal arbors of corticofugal axons to the dorsal lateral geniculate nucleus in the cat were filled with horseradish peroxidase and then partially reconstructed through serial sections. The results demonstrate that these arbors are far more complex than was suspected from previous studies of axon segments in individual sections. These axons branch profusely and spread widely within the nucleus. Within laminae A and A1 the terminal arbor of a single axon can be more than 800 micron wide compared with retinogeniculate axons whose terminal arbors range in width from 100 to 410 micron (Sur and Sherman, '82).