Term
|
Definition
| A reduction in response caused by prior or continuing stimulation |
|
|
Term
|
Definition
| A receptor that converts physical energy from the environment into neural activity |
|
|
Term
|
Definition
| the idea that the mind produces ideas that are not derived from external sources, and that we have abilities that are innate and not learned |
|
|
Term
|
Definition
| the idea that both mind and body exist |
|
|
Term
|
Definition
| the idea that mind and matter are formed from, or reducible to, a single ultimate substance or principle of being |
|
|
Term
|
Definition
| the ideea that physical matter is the only reality, and that everything can be explained through matter |
|
|
Term
|
Definition
| the idea that the mind is the true reality and objects exist only as aspects of the mind's awareness |
|
|
Term
|
Definition
| the idea positing the existence of two distinct principles of being in the universe: spirit/soul, matter/body |
|
|
Term
|
Definition
| the idea that experience from the senses is the only source of knowledge |
|
|
Term
|
Definition
| the idea that all matter has a consciousness--that mind exists as a property of all matter |
|
|
Term
|
Definition
| the science of defining quantitative relationships between physical and psychological (subjective) events |
|
|
Term
|
Definition
| the minimum distance at which two stimuli (i.e., two simultaneous touches) are just perceptible as separate |
|
|
Term
| Just Noticeable Difference (JND) |
|
Definition
| The difference threshold--the smallest detectable difference between two stimuli, or the minimum change in a stimulus that enables it to be correctly judged as different from a reference stimulus |
|
|
Term
|
Definition
| the constant of proportionality in weber's law |
|
|
Term
|
Definition
| the principle that the difference threshold is a constant fraction of the comparison stimulus |
|
|
Term
|
Definition
| A principle describing the relationship between stimulus and resulting sensation such that a magnitude of subjective sensation increases proportionally to the logarith of the stimulus intensity |
|
|
Term
|
Definition
| the minimum amount of stimulation necessary for a person to detect a stimulus 50% of the time |
|
|
Term
| Method of Constant Stimuli |
|
Definition
| psychophysical method, many stimuli ranging from rarely to almost always perceivable (or rarely to almost always perceivably different from a reference stimulus) are presented once at a time |
|
|
Term
|
Definition
| psychophysical method in which the particular dimension of a stimulus, or the difference between two stimuli, is varied incrementally until the participant responds different. |
|
|
Term
|
Definition
| the method of limits for which the subject controls the change in the stimulus |
|
|
Term
| What are the four possible outcomes when attempting to separate signal from noise? |
|
Definition
| correct rejection, a hit, false alarm, and a miss |
|
|
Term
|
Definition
| The sensitivity measure--the difference between the signal and the noise |
|
|
Term
| Receiver Operating Characteristics |
|
Definition
| in studies of signal detection, the graphical plot of the hit rate as a function of the false alarm rate. If these are the same, points fall on the diagonal, indicating that the observer cannot tell the difference between the presence and the absence of the signal. As the observer's sensitivity increases, the curve bows upward toward the upper left corner |
|
|
Term
|
Definition
| a psychophysical theory that quantifies the response of an observer to the presentation of a signal in the presence of noise. Measures attained from a series of presentations are sensitivity (d') and criterion of the observer |
|
|
Term
|
Definition
| a psychophysical method in which the participant assigns values according to perceived magnitudes of the stimuli |
|
|
Term
|
Definition
| a subject adjusts a stimulus of one sort to match the perceived magnitude of a stimulus of a completely different spot |
|
|
Term
|
Definition
| a principle describing the relationship between stimulus and resulting sensation, such that the magnitude of subjective sensation is proportional to the stimulus magnitude raised to an exponent |
|
|
Term
| Compare and differentiate between the three laws of psychophysics |
|
Definition
| Weber's law involves clear objective measurement (fractions of stimuli magnitude compared to detectable changes) Fechner's law begins with same objective ideas, but adds in assumptions on how sensations work. Stevens' power law is simply rating data. |
|
|
Term
| Doctrine of specific nerve energies |
|
Definition
| a doctrine formulated by Johannes Muller stating that the nature of a sensation depends on which sensory fibers are stimulated--not on how they are stimulated |
|
|
Term
|
Definition
| to take up light, noise, or energy and not transmit it at all |
|
|
Term
|
Definition
| to disperse light in an irregular fashion |
|
|
Term
|
Definition
| to redirect something that strikes a surface--especially light, sound, or heat--usually back toward its point of origin |
|
|
Term
|
Definition
| to conver something (e.g., light) from one place or thing to another |
|
|
Term
|
Definition
| (1) to alter the course of a wave of energy that passes into something from another medium, as water does to light entering it from the air (2) to measure the degree of refraction in a lens or eye |
|
|
Term
|
Definition
|
|
Term
|
Definition
| the transparent 'window' into the eyeball |
|
|
Term
|
Definition
| the watery fluid in the anterior chamber of the eye |
|
|
Term
|
Definition
| allowing light to pass through with no interruption so that objects on the other side can be clearly seen |
|
|
Term
|
Definition
| the lens inside the eye that enables changing focus |
|
|
Term
|
Definition
| the dark circular opening at the center of the iris in the eye, where light enters the eye |
|
|
Term
|
Definition
| the colored part of the eye, consisting of a muscular diaphragm surrounding the pupil and regulating the light entering the eye by expanding and contracting the pupil |
|
|
Term
|
Definition
| the transparent fluid that fills the vitreous chamber in the posterior part of the eye |
|
|
Term
|
Definition
| a light sensitive membrane in the back of the eye that contains rods and cones, which receive an image from the lens and send it to the brain through the optic nerve |
|
|
Term
|
Definition
| the process by which the eye changes its focus (in which the lengs gets fatter as gaze is directed toward nearer objects |
|
|
Term
|
Definition
| literally 'old sight' the loss of near vision because of insufficient accommodation |
|
|
Term
|
Definition
| opacity of crystalline lens |
|
|
Term
|
Definition
| the condition in which there is no refractive error, because the refractive power of the eye is perfectly matched to the length of the eyeball |
|
|
Term
|
Definition
| a common condition in which light entering the eye is focused in front of the retina and distant objects cannot be seen sharply |
|
|
Term
|
Definition
| a common condition in which light entering the eye is focused behind the retina |
|
|
Term
|
Definition
| a visual defect caused by the unequal curving of one or more of the refractive surfaces of the eye, usually the cornea |
|
|
Term
|
Definition
| referring to the conversion from one form of energy (e.g., light) to another (e.g., electricity) |
|
|
Term
|
Definition
| the back layer of the retinal--what the doctor sees through an ophtalmoscope |
|
|
Term
|
Definition
| light sensitive receptors in the retina |
|
|
Term
|
Definition
| photoreceptors specialized for night vision |
|
|
Term
|
Definition
| photoreceptors secialized for day-light vision, fine visual acuity, and color |
|
|
Term
|
Definition
| in reference to the retina, consisting of two parts: the rods and cones, which operate under different conditions |
|
|
Term
|
Definition
| the part of a photoreceptor that contains photopigment molecules |
|
|
Term
|
Definition
| the part of a photoreceptor that lies between the outer segment at the nucleus |
|
|
Term
|
Definition
| the location where axons terminate at the synapse for transmission of information by release of a chemical transmitter |
|
|
Term
|
Definition
| the light catching part of the visual pigments of the retina |
|
|
Term
|
Definition
| the visual pigment found in rods |
|
|
Term
|
Definition
|
|
Term
|
Definition
| an increase in membrane potential where the inner membrane surface becomes more negative than the outer membrane surface |
|
|
Term
|
Definition
| distance from the fovea. center of fovea is completely made of cones, rods further out, and cones drop off. No cones/rods in optic disc |
|
|
Term
|
Definition
| specialized retinal cells that contact both photoreceptor and bipolar cells |
|
|
Term
|
Definition
| antagonistic neural interaction between adjacent regions of the retina |
|
|
Term
|
Definition
| retinal cells found in the inner synaptic layer that make synaptic contacts with bipolar cells, ganglion cells, and one another |
|
|
Term
|
Definition
| retinal cells that synapse with either rods or cones (not both) and with horizontal cells, and then pass on signals on to galnglion cells |
|
|
Term
| diffuse (converging) bipolar cells |
|
Definition
| bipolar retinal cells whose processes are spread out to receive input from multiple cones |
|
|
Term
|
Definition
| (1) the ability to perceive via the sense organs (2) extreme responsiveness to radiation, especially in light of a specific wavelength (3) the ability to respond to transmitted signals |
|
|
Term
|
Definition
| a measure of the finest detail that can be resolved by the eyes |
|
|
Term
|
Definition
| small cone bipolar cells in the central retina that receive input from a single cone |
|
|
Term
|
Definition
| bipolar cells that respond to an increase in light captured by cones |
|
|
Term
|
Definition
| bipolar cells that respond to a decrease in light captured by the cones |
|
|
Term
|
Definition
| retinal cells that receive visual information from photoreceptors via two intermediate neuron types (bipolar cells and amacrine cells) and transmit information to the brain and midbrain |
|
|
Term
|
Definition
| the region on the retina in which visual stimuli influence a neuron's firing rate |
|
|
Term
|
Definition
| a cell that depolarizes in response to an increase in light intensity in its receptive field center |
|
|
Term
|
Definition
| A cell that depolarizes in response to a decrease in light intensity in its receptive field center |
|
|
Term
|
Definition
| a biological function that allows the passage of some frequencies and blocks the passage of others |
|
|
Term
|
Definition
| the difference in luminance between an object and the background, or between lighter and darker parts of the same object |
|
|
Term
|
Definition
| for a grating, a pair consisting of one dark bar and one bright bar |
|
|
Term
|
Definition
| the angle subtended by an object at the retina |
|
|
Term
|
Definition
| a grating with a sinusodial luminance profile |
|
|
Term
|
Definition
| misperception of a grating due to undersampling--cycle falls on single cone, so detect it is the same (cannot resolve) |
|
|
Term
|
Definition
| the number of cycles of a grating per units of visual angle (usually specified in degrees) |
|
|
Term
|
Definition
| the number of dark and bright bars per degree of visual angle |
|
|
Term
| contrast sensitivity function |
|
Definition
| a function describing how the sensitivity to contrast (defined as the reciprocal of the contrast threshold) depends on the spatial frequency (size) of the stimulus |
|
|
Term
|
Definition
| the smallest amount of contrast required to detect a pattern |
|
|
Term
| lateral geniculate nucleus |
|
Definition
| a structure in the thalamus, part of the mid-brain, that receives input from the retinal ganglion cells and has input and output connections to the visual cortex (C I? I C I C!) |
|
|
Term
|
Definition
| the neurons in the bottom two layers of the lateral geniculate nucleus, which are physically larger than those in the top four layers |
|
|
Term
|
Definition
| the neurons in the top four layers of the LGN which are physically smaller than those in the bottom two layers |
|
|
Term
|
Definition
| the orderly mapping of the world in the lateral geniculate nucleus and the visual cortex |
|
|
Term
| Primary Visual Cortex (V1, Striate Cortex) |
|
Definition
| the area of the cerebral cortex of the brain that receives direct inputs from the lateral geniculate nucleus, as well as feedback from other brain areas, and is responsible for processing visual information |
|
|
Term
|
Definition
| the amount of cortical area (usually specified in millimeters) devoted to a specific region in the visual field (e.g., more cortical magnification for the fovea) |
|
|
Term
| Receptive fields in the striate cortex |
|
Definition
| concerned with stripes, not spots |
|
|
Term
|
Definition
| the tendency of neurons in the striate cortex to respond optimally to certain orientation, and less to others |
|
|
Term
|
Definition
| the property of the receptive fields of the striate cortex neurons by which they demonstrate a preference, responding somewhat more rapidly, when a stimulus is presented to one eye than when a stimulus is presented in one eye than when it is presented in the other |
|
|
Term
|
Definition
| A cortical neuron, with clearly defined excitatory and inhibitory regions |
|
|
Term
|
Definition
| A neuron whose receptive field characteristics cannot be easily predicted by mapping the spots of light. Prefers moving lines? And is not phase sensitive. |
|
|
Term
|
Definition
| the process by which a cell in the cortex first increases its firing rate as the bar length increases to fill up its receptive fields, and then decreases its firing rate as the bar is lengthened further |
|
|
Term
| Middle (mid-level) vision |
|
Definition
| a loosely defined stage of visual processing that comes after basic features have been extracted from the image (early vision) and before object recognition and scene understanding (high-level vision) |
|
|
Term
|
Definition
| a contour that is perceived, even though nothing changes from one side of the contour to the other in the image |
|
|
Term
|
Definition
| a school of thought believing that complex objects or perceptions could be understood by analysis of the components |
|
|
Term
|
Definition
| school of thought stressing that the perceptual whole could be greater than the apparent sum of the parts |
|
|
Term
|
Definition
| a set of rules describing which elements in an image will appear to group together. The original list was assembled by members of the gestalt school of thought |
|
|
Term
|
Definition
| a gestalt grouping rule stating that two elements will tend to group together if they seem to lie on the same contour |
|
|
Term
|
Definition
| Assumption that if contour completion, something is likely occluding object |
|
|
Term
|
Definition
| carving an image into regions of common texture properties |
|
|
Term
|
Definition
| a gestalt grouping rule stating that the tendency of two features to group together will increase as the similarity between them increases |
|
|
Term
|
Definition
| gestalt grouping rule stating that the tendency of two features to group together will increases as the distance between them decreases |
|
|
Term
|
Definition
| a rule of figure ground assignment stating that parallel contours are likely to belong to the same figure |
|
|
Term
|
Definition
| a rule for figure-ground assignment stating that symmetrical regions are more likely to be seen as a figure |
|
|
Term
|
Definition
| a gestalt grouping rule stating that two features will tend to group together if they appear to be part of the same larger region |
|
|
Term
|
Definition
| a gestalt grouping rule stating that two items will tend to group togetehr if they are connected |
|
|
Term
|
Definition
| a visual stimulus that gives rise to two or more interpretations of its identity or structure |
|
|
Term
|
Definition
| an outline that is perceptually bi-stable. Unlike the situation with most stimuli, two interpreations continually battle for perceptual dominance |
|
|
Term
|
Definition
| ever stimulus is seen as simply as possible--if ambiguous, pick most simple |
|
|
Term
|
Definition
| a viewing position that produces some regularity in the visual image that is not present in the world (i.e., something lines up perfectly in your view that confuses your evaluation) |
|
|
Term
|
Definition
| the process of determining that some regions of an image belong to a foreground object (figure) and other regions are part of the background (ground) |
|
|
Term
|
Definition
| a rule for figure ground assignment stating that if one region is entirely surrounded by another, it is likely that the surrounded region is the figure |
|
|
Term
|
Definition
| things that are moving together get grouped togetehr |
|
|
Term
|
Definition
| the degree to which two line segments appear to be part of the same contour |
|
|
Term
|
Definition
| a feature of an object that is not dependent on the exact (or accidental) viewing position of the observer |
|
|
Term
| What are some challenges of object perception? |
|
Definition
| inverse projection, segmentation (differing object from background), completion (occlusion yet still see), viewpoint invariance (objects look different from different viewpoints, but somehow we see them as the same object), differentiating illumination edges dfrom reflectance edges, and the binding problem |
|
|
Term
| why does the 3D nature of the world pose a problem for our visual system |
|
Definition
| it's back to the ill-posed problem--we receive 2-D, inverse images on our eyes, yet somehow we orient these into informative, 3-D interpreations |
|
|
Term
|
Definition
| his idea of figure-ground assignment--differing objects |
|
|
Term
| differentiating illumination |
|
Definition
| we recognize that light comes from a above direction, different shading, it helps us deterimine basic imagery |
|
|
Term
| neurons respond maximally to gestalt principles.... |
|
Definition
| good continuation and similarity |
|
|
Term
| why does the 3D nature of the world pose a problem for our visual system |
|
Definition
| it's back to the ill-posed problem--we receive 2-D, inverse images on our eyes, yet somehow we orient these into informative, 3-D interpreations |
|
|
Term
|
Definition
| his idea of figure-ground assignment--differing objects |
|
|
Term
| differentiating illumination |
|
Definition
| we recognize that light comes from a above direction, different shading, it helps us deterimine basic imagery |
|
|
Term
| neurons respond maximally to gestalt principles.... |
|
Definition
| good continuation and similarity |
|
|
Term
| why does the 3D nature of the world pose a problem for our visual system |
|
Definition
| it's back to the ill-posed problem--we receive 2-D, inverse images on our eyes, yet somehow we orient these into informative, 3-D interpreations |
|
|
Term
|
Definition
| his idea of figure-ground assignment--differing objects |
|
|
Term
| differentiating illumination |
|
Definition
| we recognize that light comes from a above direction, different shading, it helps us deterimine basic imagery |
|
|
Term
| neurons respond maximally to gestalt principles.... |
|
Definition
| good continuation and similarity |
|
|
Term
|
Definition
| things that are moving together get grouped togetehr |
|
|
Term
|
Definition
| the degree to which two line segments appear to be part of the same contour |
|
|
Term
|
Definition
| a feature of an object that is not dependent on the exact (or accidental) viewing position of the observer |
|
|
Term
| What are some challenges of object perception? |
|
Definition
| inverse projection, segmentation (differing object from background), completion (occlusion yet still see), viewpoint invariance (objects look different from different viewpoints, but somehow we see them as the same object), differentiating illumination edges dfrom reflectance edges, and the binding problem |
|
|
Term
|
Definition
| the fact that an infinite set of different wavelength-intensity combinations can elicit exactly the same response from a single type of photoreceptor type cannot make color discriminations based on wavelength |
|
|
Term
|
Definition
| the theory that the color of any light is defined in our visual system by the relationships of three numbers; the outputs of three receptors types now known to be the three cones |
|
|
Term
|
Definition
| different mixtures of wave-lengths that look identical. More generally, any pair of stimuli that are perceived as identical in spite of physical differences |
|
|
Term
|
Definition
| a mixture of lights. If light A and light B are both reflected from a surface to the eye, in the perception of color and effects of those two lights add together |
|
|
Term
| subtractive color mixture |
|
Definition
| a mixture of pigments. If pigments A and B mix, some of the light shining on the surface will be subtracted by A, and some by B. Only the remainder contributes to the perception of color |
|
|
Term
|
Definition
| the three-dimensional space, established because color perception is based on the outputs of three cone types that describes the set of all colors (hue, saturation, brightness) |
|
|
Term
|
Definition
| the chromatic (colorful) aspect of color |
|
|
Term
|
Definition
| the chromatic strength of a hue; white has zero saturation, pink is more saturated, and red is fully saturated |
|
|
Term
|
Definition
| the distance from black (zero brightness) in color space |
|
|
Term
|
Definition
| the theory that perception of color is based on the output of three mechanisms, each of them based on an opponency between two colors; red-green, blue-yellow, and black-white |
|
|
Term
|
Definition
| a neuron whose output is based on a difference between sets of cones |
|
|
Term
|
Definition
| a visual image seen after the stimulus has been removed |
|
|
Term
|
Definition
| a stimulus whose removal produces a change in visual perception or sensitivity |
|
|
Term
|
Definition
| an afterimage whose polarity is the opposite of an original stimulus. light stimuli produce dark negative afterimages. Colors are complementary, for example, red-green, yellow-blue |
|
|
Term
|
Definition
| the point at which an opponent color mechanism is generating no signal. If red-green and blue-yellow mechanisms are at their neutral points, a stimulus will appear achromatic (over shoot with negative afterimages) |
|
|
Term
|
Definition
| inability to perceive colors that is caused by damage to the central nervous system |
|
|
Term
|
Definition
| an individual who suffers from color blindness that is due to the absence of M-cones |
|
|
Term
|
Definition
| an individual who suffers from color blindness that is due to abscend of L cones |
|
|
Term
|
Definition
| an individual who suffers from color blindness that is due to abscend of S cones |
|
|
Term
|
Definition
| a better term for what is usually called 'color-blind'. Most color blind individuals can still make discriminations based on wavelength. Those discriminations are different from the normal--that is anomalous. Flatter color experience |
|
|
Term
|
Definition
| an individual with only one cone type. Truly colorblind |
|
|
Term
|
Definition
| an indivudal with no cones. Badly visually impaired in bright light |
|
|
Term
|
Definition
| a failure to recognize objects in spite of the ability to see them. Agnosia is typically due to brain damage |
|
|
Term
|
Definition
| an inability to name objects in spite of the ability to see and recognize them (as shown by usage). Anomia is typically due to brain damage |
|
|
Term
|
Definition
| in sensation and perception, the idea that basic perceptual experiences (e.g., color perceptions) may be determined in par by the cultural environment |
|
|
Term
|
Definition
| a color that can be experienced in isolation |
|
|
Term
|
Definition
| a color, such as brown or gray, that is seen only in relation to other colors. A 'gray' patch in complete darkness appears white |
|
|
Term
|
Definition
| the light that illuminates a surface |
|
|
Term
| spectral reflectance function |
|
Definition
| the function relating the wavelength of light to the percentage of that wavelength that is reflected from a surface |
|
|
Term
| spectral power distribution |
|
Definition
| the physical energy in a light as a function of wavelength |
|
|
Term
|
Definition
| the tendency of a surface to appear the same color under a fairly wide range of illuminants |
|
|
Term
|
Definition
| the percentage of light hitting a surface that is reflected and not absorbed into the surface. Typically, reflectance is given as a function of wavelength |
|
|
