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Chapter 10 Phys Psyc
| Question | Answer |
|---|---|
| What is the visual field? | The whole area that you can see without moving your head or eyes. |
| ___ ____ is the sharpness of vision. | Visual Acuity |
| What are photoreceptors? | Neural cells in the retina that respond to light. |
| ____ ____ is the phenomenon by which interconnected neurons inhibit their neighbors, producing contrast at the edges of regions. | Lateral Inhibition |
| What is the cornea? | The transparent outer layer of the eye, whose curvature is fixed. It bends light rays and is primarily responsible for forming the image on the retina. |
| What is lens? | A structure in the eye that helps focus an image on the retina. |
| ____ is the bending of light rays by a change in the density of a medium, such as the cornea and the lens of the eye. | Refraction |
| ___ ___ is one of the muscles that controls the shape of the lens inside the eye, focusing an image on the retina. | Ciliary Muscle |
| What is accommodation? | The process of focusing by the cilliary muscles and the lens to form a sharp image on the retina. |
| ___ is the aperture, formed by the iris, that allows light to enter the eye. | Pupil |
| What is the iris? | The circular structure of the eye that provides an opening to form the pupil. |
| ____ ___ is one of the muscles attached to the eyeball that control its position and movements. | Extraocular Muscle |
| ____ is the receptive surface inside the eye that contains photoreceptors and other neurons. | Retina |
| This is a class of light-sensitive receptor cells in the retina that are most active at low levels of light. | Rod |
| This is a class of photoreceptor cells in the retina that are responsible for color vision. | Cone |
| Bipolar cells are what? | A class of interneurons of the retina that receive information from rods and cones and pass the information to retinal ganglion cells. |
| What are ganglion cells? | A class of cells in the retina whose axons form the optic nerve. |
| What is the optic nerve? | Cranial Nerve II; the collection of ganglion cell axons that extend from the retina to the optic chiasm. |
| ____ ____ are specialized retinal cells that contact both the receptor cells and the bipolar cells. | Horizontal Cells |
| ____ ___ are specialized retinal cells that contact both the bipolar cells and the ganglion cells, and are especially significant in inhibitory interactions within the retina. | Amacrine Cells |
| What is the scotopic system? | A system in the retina that operates at low levels of light and involves the rods. |
| ____ ___ is a system in the retina that operates at high levels of light, shows sensitivity to color, and involves the cones. | Photoptic System |
| ____ is the photopigment in rods that responds to light. | Rhodopsin |
| What is retinal? | One of the two components of photopigments in the retina. |
| What is opsin? | One of the two components of photopigments in the retina. |
| What is the receptive field? | The stimulus region and features that cause the maximal response of a cell in a sensory system. |
| _____ ___ ___ is a retinal bipolar cell that is inhibited by light in the center of its receptive field. | Off-center Bipolar Cell |
| The on-center bipolar cell is what? | A retinal bipolar cell that is excited by light in the center of its receptive field. |
| What is the on-center ganglion cell? | A retinal ganglion cell that is activated when light is presented to the center, rather than the peripery, of the cell's receptive field. |
| What is the off-center ganglion cell? | A retinal ganglion cell that is activated when light is presented to the periphery, rather than the center, of the cell's receptor field. |
| What is range franctionation? | A hypothesis of stimulus intensity perception stating that a wide range of intensity values can be encoded by a group of cells, each of which is a specialist for a particular range of stimulus intensities. |
| What is fovea? | The central portion of the retina, packed with the most photoreceptors and therefore the center of our gaze. |
| ___ ___ is the region of the retina devoid of receptor cells because ganglion cell axons and blood vessels exite the eyeball there. | Optic Disc |
| What is a blind spot? | The place through which blood vessels enter the retina. Because there are no receptors in this region, light striking it cannot be seen. |
| What is the primary visual cortex (V1)? | It is also called striate cortex or area 17. The region of the occipital cortex where most visual information first arrives. |
| What is scotoma? | A region of blindness caused by injury to the visual pathway or brain. |
| What is optic chiasm? | The point at which the two optic nerves meet. |
| ___ ___ are the axons of retinal ganglion cells after they have passed the optic chiasm; most terminate in the lateral geniculate nucleus. | Optic Tract |
| What is the lateral geniculate nucleus (LGN)? | The part of the thalamus that receives information from the optic tract and sends it to the visual areas in the occipital cortex. |
| ___ ____ are axons from the lateral geniculate nucleus that terminate in the primary visual areas of the occipital cortex. | Optic Radiation |
| The ____ ___ is also called the visual cortex. The cortex of the occipital lobe of the brain. | Occipital Cortex |
| ___ ___ is the primary visual cortex. | Striate Cortex (V1) |
| This is the visual cortex outside of striate cortex. | Extrastriate Cortex |
| What is on-center/off-surround? | Refers to a concentric receptive field in which the center excites the cell of interest while the surround inhibits it. |
| What is off-center/on-surround? | Refers to a concentric receptive field in which the center inhibits the cell of interest while the surround excites it. |
| What is parvocellular? | Of or consisting of relatively small cells. |
| _____ is or or consisting of relatively large cells. | Magnocellular |
| What is a simple cortical cell? | This is also called bar detector or edge detector. A cell in the visual cortex that responds best to an edge or a bar that has a particular width, as well as a particular orientation and location in the visual field. |
| What is complex cortical cell? | A cell in the visual cortex that responds best to a bar of a particular size and orientation anywhere within a particular area of the visual field. |
| What is the spatial-frequency filter model? | A model of pattern analysis that emphasizes Fourier analysis of visual stimuli. |
| ____ ____ ___ is a region of cortex in which one eye of the other provides a greater degree of snaptic input. | Ocular Dominance Column |
| ___ ___ ___ is a slab of visual cortex, in which the neurons of all layers respond preferentially to stimulation of one eye. | Ocular Dominance Slab |
| What is the orientation column? | A column of visual cortex that responds to rod-shaped stimuli of a particular orientation. |
| What is a blob? | Also called peg, a region of visual cortex distinguished by stains for the enzyme cytochrome oxidase. |
| What is the trichromatic hypothesis? | A hypothesis of color perception stating that there are three different types of cones, each excited by a different region of the spectrum and each having a seperate pathway to the brain. |
| ____ ____ ___ is the theory that color vision depends on systems that produce opposite responses to light of different wavelengths. | Opponent-process hypothesis. |
| ____ ____ ___ is a visual receptor cell that has opposite firing responses to different regions of the spectrum. | Spectrally Opponent Cell |
| What is ataxia? | An impairment in the direction, extent, and rate of muscular movement. |
| ___ ____ is a neuron that is active when an individual makes a particular movement, but is also active when that individual sees another individual make that same movement. | Mirror Neuron |
| What is myopia? | Nearsightedness; the inability to focus the retinal image of objects that are far away. |
| What is amblyopia? | Reduced visual acuity that is not caused by optical or retinal impairments. |