RT Book, Section A1 Berkowitz, Aaron L. SR Print(0) ID 1160203596 T1 The Visual Pathway and Approach to Visual Loss T2 Clinical Neurology and Neuroanatomy: A Localization-Based Approach YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9781259834400 LK neurology.mhmedical.com/content.aspx?aid=1160203596 RD 2024/11/11 AB The optic nerve is the output of the retina. Therefore, each optic nerve carries all of the visual information from the eye from which it emerges. Since the left hemisphere moves the right side of the body and the right hemisphere moves the left side of the body, it makes sense that the left hemisphere should receive the visual information from the right half of the world and the right hemisphere should receive the visual information from the left half of the world. Therefore, some of the information in each optic nerve must cross so that the brain can work with the left and right visual fields rather than merely what is seen by the left and right eyes: The left hemisphere must receive right visual field information from both the left eye and the right eye; the right hemisphere must receive left visual field information from both the left eye and the right eye. The crossing of visual field information to convert the visual world from left eye–right eye organization to left field–right field organization occurs at the optic chiasm. Posterior to the optic chiasm, visual information is organized into fields: the left visual field is processed in the right hemisphere, and the right visual field in the left hemisphere.