Figure 8.

Schematic diagram of structures involved in horizontal gaze, including the abducens (VIth) nucleus, the medial longitudinal fasciculus (MLF), the oculomotor (IIIrd) nucleus, the abducens (VIth) and oculomotor (IIIrd) nerves, and the lateral and medial rectus muscles. Note the two neuronal populations in the abducens nucleus. The abducens nucleus is comprised of two populations of neurons: motor neurons that project ipsilaterally to the lateral rectus and interneurons that form the medial longitudinal fasciculus. Both neuron types are present throughout the nucleus, though more interneurons are present rostrally and more motor neurons caudally.