PHENOMENA OF FLUCTUATION, EXTINCTION AND COMPLETION IN VISUAL PERCEPTION

OF THE various systems which subserve perception in the primate organism, perhaps none has been better explored than the visual apparatus. A good deal of information on the optic pathways has been obtained by the anatomist and the clinician. According to Brouwer and Zeeman,¹ Brouwer² and Poliak,³ the visual fibers originating in the retina follow an orderly path and seem to show throughout a point for point relationship to the occipital cortex. However, from the functional standpoint the concept of point for point representation is not altogether tenable. Recent physiologic and clinical investigations have revealed that a mechanism such as the "peaking of excitation processes" in widely overlapping neurons provides a better hypothesis for visual function.⁴ Talbot and Marshall's animal experiments show that this dynamic representation furnishes a closer correspondence between retina and visual cortex than any fiber per fiber relationship could ever yield to the