AP Psych: Unit 3 - Sensation and Perception (3.1 - 3.2)

sensation

the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment

sensory receptors

sensory nerve endings that respond to stimuli

perception

the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events

bottom up processing

analysis that begins with the sensory receptors and works up to the brain's integration of sensory information

top down processing

information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations

selective attention

the focusing of conscious awareness on a particular stimulus

inattentional blindness

failing to see visible objects when our attention is directed elsewhere

change blindness

failing to notice changes in the environment; a form of inattentional blindness

transduction

conversion of one form of energy into another. in sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret

psychophysics

the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them

absolute threshold

the minimum stimulus energy needed to detect a particular stimulus 50 percent of the time

signal detection theory

a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and alertness.

subliminal

below one's absolute threshold for conscious awareness

difference threshold

the minimum difference between two stimuli required for detection 50 percent of the time

priming

the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response

Weber's law

the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)

sensory adaptation

diminished sensitivity as a consequence of constant stimulation

perceptual set

a mental predisposition to perceive one thing and not another

parallel processing

processing many aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision

gestalt

an organized whole. gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes

figure ground

the organized of the visual field into objects (the figures) that stand out from their surroundings (the ground)

grouping

the perceptual tendency to organize stimuli into coherent groups

depth perception

the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance

visual cliff

a laboratory device for testing depth perception in infants and young animals

binocular cue

a depth cue, such as retinal disparity, that depends on the use of two eyes

retinal disparity

a binocular cue for perceiving depth. by comparing retinal images from the two eyes, the brain computed distance- the greater the disparity (difference) between the two images, the closer the object

monocular cue

depth cues, such as interposition and linear perspective, available to either eye alone