Convergence, divergence, pupillary reactions and accommodation of the eyes from faradic stimulation of the macaque brain

The neuroanatomical pathways involved in eye movements and in the control of the intrinsic eye muscles are of widespread clinical and experimental interest although still poorly understood.Most of the investigations carried out to date have been devoted to the conjugate gaze mechanism, pupillary dilatation as related to the autonomic nervous system, and the pupillary light reflex.Little attention has been given to the anatomical pathways involved in convergence, divergence, and the "near" reflex.Several authors have obtained convergence from faradic stimulation of the cerebral cortex in the cat, the monkey, the chimpanzee, and man (Schafer, 1888a;Russel, 1894; Leyton and Sherrington, '17; Spiegel and Scala, '37; Rasmussen and Penfield, '48).A few authors have obtained divergence from cortical stimulation in the cat and monkey (Spiegel and Scala, '37; Crosby, Yoss and Henderson, '52).