IN 1936 Schubert and Burian1 published their discovery of the pupillary fusion reflex (Fusionreaktion), which was defined as a dilatation of the pupil with a disruption of fusion and, conversely, a constriction of the pupil with its resumption. This reflex was stated to be not evanescent but lasting. Since that time no further report has been published on the subject.
During an investigation of the pupillary near reflex2 the question that the fusion reflex may be an artefact arose. In finding the relationship of pupillary diameter to accommodation and the various components of convergence, as originally divided by Maddox3 and quantified by others,4 we determined that the pupillary near reflex is essentially elicited by accommodation. Fusional convergence plays a minor role in some subjects but none at all in others. A psychic proximal factor in the pupillary near reflex was indicated, but it is of no
MARG E, MORGAN MW. THE PUPILLARY FUSION REFLEX. Arch Ophthalmol. 1950;43(5):871-878. doi:10.1001/archopht.1950.00910010886012