AP PSYCH: Sensation and Perception

perception

the process of selecting, organizing, and interpreting sensory information, which enables us to recognize meaningful objects and events

relative size

a depth cue whereby larger objects are perceived as closer than smaller ones

organ of corti

a group of cells that rest on the membrane; hair cells bend when the basilar membrane is moved

place theory

hair cells at a particular place on the basilar membrane respond most to a particular frequency **AKA: traveling wave theory

difference threshold/just noticeable difference (JND)

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

absolute threshold

minimum stimulation needed to detect a particular stimulus 50% of the time

frequency

rate at which the sound waves alternates between high and low air pressures

Transduction

receptors convert the stimulus into neural signals by firing an action potential and releasing neurotransmitters that send signals to neighboring cells

sensation

system of messages from the senses that make up the raw information that affects many kinds of behavior and mental processes

cornea

the curved, transparent, protective layer through which light rays enter the eye

basilar membrance

the floor of the fluid-filled duct that runs through the cochlea

retinal disparity/binocular stereopsis

a binocular cue for perceiving depth; depth cues that involve comparing the image from the two eyes

selective attention

ability to focus on a specific aspect or characteristic of a task while ignoring all other, possibly more salient, aspects (Zentall 1993) **AKA: innattentional blindness and "cocktail party phenomenon"

auditory cortex

area in the temporal lobe that is first to receive information about sounds from the thalamus

bottom-up processing

aspect of recognition that depends on basic information from sensory receptors **large-scale features (shape)

top-down processing

aspect of recognition that is guided by higher level cognitive processes and psychological factors **knowledge, expectations

auditory nerve

bundle of axons that carry stimuli from the hair cells of the cochlea to the brain

iris

colorful part of the eye, constricts and relaxes to adjust the amount of light entering the eye

loudness

determined by the amplitude of the sound wave; greater amplitude produces sensations of louder sounds

sensory adaptation

diminished sensitivity as a consequence of constant stimulation **wearing a new piece of jewelry

cochlea

fluid-filled spiral structure in the ear in which auditory transduction occurs

pitch

how high or low a tone sounds; depends on frequency

light and shadow

nearby objects reflect more light into our eyes than more distant objects **closer=brighter and further=dimmer

relative motion

objects closer to a fixation point move faster and in the opposing direction to those further away

proximity

objects near each other tend to be grouped together **students in the back of the room

relative height

objects that are closer to the top of our visual field usually appears to be more distant

interposition

objects that occlude (block) other objects tend to be perceived as closer

pupil

opening in the iris of the eye where light passes to the retina, located just behind the cornea

size constancy

our brain corrects the perceived size of an object to adjust for its apparent distance

linear perspective

parallel lines appear to converge (intersect) in the distance **railroad tracks

lens

part of the eye behind the pupil that bends light rays

signal detection theory/ hit or miss grid

predicts how and when we detect the presence of a faint stimulus (signal) amid background noise

psychophysics

research area focused on the relationship between physical characteristics of environment and our psychological experience with them ** sound ----> volume

Weber's law

two stimuli must differ by a constant minimum percentage (rather than amount) to be perceived as different **gained weight on a ballerina vs. football player

priming/subliminal priming

unconscious increased sensitivity to certain stimuli due to prior experience

subliminal stimulation

when stimuli is below one's absolute threshold for conscious awareness