The author has done a great deal of experimental work during the last twenty years on pupillary, palpebral, lenticular and proptosing and retracting phenomena, as well as on paradoxical phenomena, following lesions of the afferent affective and proprioceptive paths, with and without the administration of various drugs, and with and without interruptions in the various efferent paths to the internal and external musculature of the eye. The results of more than 900 experiments on animals (mostly cats) are used by the author as a basis for his conclusions.
Byrne sums up by saying that the pupillary, palpebral and lens effector mechanisms consist of A, B and C. a narrowing or constrictor set (parasympathetic), and of A1,B1 and C1, a widening or dilator set (sympathetic).
A and A1 are least differentiated and at a chemical effector level, mediating paradoxical pupillary constriction and dilatation