Who discovered that rods and cones are the eye’s photoreceptors?

II CICLO DE CONFERENCIAS SOBRE HISTORIA DE LA ÓPTICA
A preeminent quest of 19th-century visual neuroscience was to identify the anatomical elements of the retina that respond to light. A major breakthrough came in 1854, when Carl Bergmann discovered through direct observation that the human fovea contains only rods and cones. Based on this, he argued that these must necessarily be the light-sensitive elements (i.e., photoreceptors) that initiate vision. Bergmann also argued that Henle’s fibers form part of the necessary anatomical link between the distal rods and cones and the proximal ganglion cells that transmit visual signals to the brain via the optic nerve. However, despite his achievement, Heinrich Müller, not Bergmann, is remembered in the literature as the discoverer of human photoreceptors. The aim of this lecture is to correct the historical record by situating Bergmann’s work alongside that of his contemporaries. I will review his observations, arguments, and the critique he received while making this history accessible for current readers by comparing what was said to what we know now. I will conclude that Bergmann’s arguments are at least as compelling as those of Müller, and therefore he should be recognized as a co-discoverer of the anatomic site in the retina where vision is initiated.
Biografía del conferenciante: Larry N. Thibos se formó en la Universidad de Michigan, donde obtuvo los títulos de B.S. (1970) y M.S. (1972) en Ingeniería Eléctrica, y en la Universidad de California, Berkeley, donde recibió el título de doctor en Óptica Fisiológica (1975). Entre 1975 y 1983, fue investigador en el John Curtin School of Medical Research de la Australian National University en Canberra, Australia, donde estudió la neurofisiología del procesamiento de información retiniana. En 1983, se incorporó a la facultad de la Escuela de Optometría de la Universidad de Indiana (Bloomington, IN), donde actualmente es Profesor Emérito. Sus intereses de investigación incluyen los efectos de las aberraciones ópticas del ojo en el rendimiento visual, los límites de la visión espacial impuestos por la arquitectura retiniana y la caracterización de la visión en el campo periférico.