 | Term | Definition |
| |
gestalt |
a German word that roughly refers to the whole form, pattern, or configuration that a person perceives |
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perceptual constancy |
the phenomenon that allows us to perceive objects as maintaining stable properties, such as size, shape, and brightness, despite differences in distance, viewing angle, and lighting |
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depth perception |
the ability to perceive the visual world in three dimensions and to judge distances accurately |
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binocular depth cues |
depth cues that depend on both eyes working together |
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monocular depth cues |
depth cues that can be perceived by one eye alone |
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real motion |
perceptions of motion tied to movements of real objects through space |
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apparent motion |
perceptions of motion that seem to be psychologically constructed in response to various kinds of stimuli |
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phi phenomenon |
apparent motion that occurs when several stationary lights in a dark room are flashed on and off in sequence, causing the perception that a single light is moving from one spot to the next |
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autokinetic illusion |
apparent motion caused by the movement of the eyes rather than the movement of the objects being viewed |
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illusion |
a false perception or a misperception of an actual stimulus in the environment |
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bottom-up processing |
information processing in which individual components of a stimulus are combined in the brain and prior knowledge is used to make inferences about these patterns |
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top-down processing |
information processing in which previous experience and conceptual knowledge are applied in order to recognize the nature of a whole and then logically deduce the individual components of that whole |
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perceptual set |
an expectation of what will be perceived, which can affect what actually is perceived |
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attention |
the process of sorting sensations and selecting some for further processing |
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inattentional blindness |
the phenomenon in which we shift our focus from one object to another and, in the process, fail to notice changes in objects to which we are not directly paying attention |
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subliminal perception |
the capacity to perceive and respond to stimuli that are presented below the threshold of awareness |
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extrasensory perception |
gaining information about objects, events, or another person's thoughts through some means other than the known sensory channels |
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sensation |
the process through which the senses pick up visual, auditory, and other sensory stimuli and transmit them to the brain |
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perception |
the process by which sensory information is actively organized and interpreted by the brain |
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absolute threshold |
the minimum amount of sensory stimulation that can be detected 50% of the time |
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difference threshold |
a measure of the smallest increase or decrease in a physical stimulus that is required to produce a difference in sensation that is noticeable 50% of the time |
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just noticeable difference |
the smallest change in sensation that a person is able to detect 50% of the time |
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weber's law |
the law stating that just noticeable difference for all senses depends on a proportion or percentage of change in a stimulus rather than on a fixed amount of change |
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sensory receptors |
highly specialized cells in the sense organs that detect and respond to one type of sensory stimuli-light, sound, or odor, for example-and transduce (convert) the stimuli into neural impulses |
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transduction |
the process through which sensory receptors convert the sensory stimulation into neural responses |
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sensory adaptation |
the process in which sensory receptors grow accustomed to constant, unchanging levels of stimuli over time |
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visible spectrum |
the narrow band of electromagnetic waves that are visible to the human eye |
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cornea |
the tough, transparent, protective layer that covers the front of the eye and bends light rays inward through the pupil |
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lens |
the transparent disc-shaped structure behind the iris and the pupil that changes shape as it focuses on objects at varying distances |
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accommodation |
the flattening and bulging action of the lens as it focuses images of objects on the retina |
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retina |
the layer of tissue that is located on the inner surface of the eyeball and and contains sensory receptors for vision |
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rods |
the light sensitive receptor cells in the retina that look like slender cylinders and allow the eye to respond to as few as five photons of light |
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cones |
the light sensitive, rounded receptor cells in the retina that enable humans to see color and fine detail in adequate light but to do not function in very dim light |
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fovea |
a small area at the center of the retina that provides the clearest and sharpest vision because it has the largest concentration of cones |
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blind spot |
the point in which retina where there are no rods or cones because the cables of ganglion cells is extending through the retina wall |
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frequency |
the number of cycles completed by a sound wave in one second, determining the pitch of the sound; measured in the unit called the hertz |
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amplitude |
the measure of the loudness of a sound; expressed in the unit called the decibel |
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decibel |
a unit of measurement for the loudness of sounds |
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timbre |
the distinctive quality of a sound that distinguishes it from other sounds of the same pitch and loudness |
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audition |
the sensation and process of hearing |
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conduction deafness |
conductive hearing loss is caused by disease or by injury to the ear drum or to the bones of the middle ear, preventing sounds waves from being conducted to the cochlea |
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sensorineural hearing loss |
involves damage to either the cochlea or the auditory nerve. large numbers of the cochlea's delicate hair cells, which transduce sound waves into neural impulses, may be damaged or destroyed |
