Key Terms

6.1 An Overview of the Visual System

Wavelength, electromagnetic spectrum, visible spectrum, cornea, crystalline lens, retina, aqueous humor, vitreous humor, photoreceptors, retinal ganglion cells, optic nerve, optic disk, fovea, choroid, sclera

6.2 The Retina

Phototransduction, receptors, bipolar cells, horizontal cells, amacrine cells, depolarized resting potential, visual pigment molecules, rhodopsin, opsin, 11-cis retinal, cGMP,, short/middle/long wavelength cones

6.3 Visual Processing Begins in Bipolar, Horizontal, Amacrine and Ganglion Cells

receptive field, center/surround, on-center and off-center bipolar cells, on-center and off-center ganglion cell, contrast, “magnocellular” cells, “parvocellular” ganglion cells, high-acuity vision, superior colliculus, intrinsically photosensitive ganglion cells (ipRGCs), circadian rhythms, three primary colors, complementary colors, opponent colors, achromatic ganglion cells, “off response”, red/green ganglion cells, opponent-color cells, blue/yellow ganglion cells

6.4 The Thalamus and Primary Visual Cortex

lateral geniculate nucleus of the thalamus (LGN), primary visual cortex, extrastriate visual areas, inferotemporal cortex, fixation point, visual field, magnocellular layers 1 and 2, parvocellular layers 3-6, koniocellular, retinotopic map, functional architecture, angle of orientation, simple cells, complex cells, directionally selective, sinusoidal luminance gratings, endstopping, narrowly tuned, binocular neurons, ocular dominance, functional anatomy, orientation columns, optical recording, cytochrome oxidase blobs, orientation pinwheels, cortical layers, layer 4

6.5 Extrastriate Cortex

dorsal pathway, ventral pathway, inferotemporal cortex, area MT, face patches, fusiform face area

6.6 Unsolved Questions In Visual Perception

binding problem, “bottom-up” vs “top down”, convergence, grandmother cells, ensemble, prosopagnosia, gnostic neurons