chp 6/7 sensation and perception amsco AP psychology

first 51 terms are chp 7 and the rest are chp 6

absolute threshold

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

binocular cues

depth cues, such as retinal disparity, that depend on the use of two eyes

bottom-up processing (feature analysis)

we use only the features of the object itself to perceive it

change blindness

failing to notice changes in the environment

color constancy

the ability to recognize colors despite changes in lighting

deductive reasoning

reasoning in which a conclusion is reached by stating a general principle and then applying that principle to a specific case (The sun rises every morning; therefore, the sun will rise on Tuesday morning.)

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

difference threshold

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

divided attention

concentrating on more than one activity at the same time

extrasensory perception (ESP)

the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition

feature detectors

nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement

Firgure-ground

the organization of the visual field into objects that stand out from their surroundings

focused (selective) attention

the ability to disregard unimportant stimuli

Gestalt

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

grouping

the perceptual tendency to organize stimuli into coherent groups

Habituation

decreasing responsiveness with repeated stimulation. As infants gain familiarity with repeated exposure to a visual stimulus, their interest wanes and they look away sooner.

inductive reasoning

specific to general

Interposition

if one object partially blocks our view of another, we perceive it as closer

light and shadow

Nearby objects reflect more light to eyes. Given two identical objects, the dimmer one seems farther away

lightness constancy

we perceive an object as having a constant lightness even while its illumination varies

linear perspective

A monocular cue for perceiving depth; the more parallel lines converge, the greater their perceived distance.

monocular cues

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

moon illusion

A visual illusion involving the misperception that the moon is larger when it is on the horizon than when it is directly overhead.

motion parallax

a depth cue in which the relative movement of elements in a scene gives depth information when the observer moves relative to the scene

Muller-Lyer Illusion

illusion of line length that is distorted by inward-turning or outward-turning corners on the ends of the lines, causing lines of equal length to appear to be different

parapsychology

the study of paranormal phenomena

Perception

The act of becoming aware through the senses

perceptual adaption

the ability to adjust to an artificially displaced or even inverted visual field

perceptual constancy

perceiving objects as unchanging even as illumination and retinal images change

perceptual set

a readiness to perceive a stimulus in a particular way

phi phemomenon

an illusion of movement created when two or more adjacent lights blink on and off in quick succession

Ponzo illusion

An illusion of size in which two objects of equal size that are positioned between two converging lines appear to be different in size. Also called the railroad track illusion.

Psychophysics

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

relative clarity

hazy object seen as more distant

relative height

higher objects seen as more distant

relative motion

movement in relation to a frame of reference

relative size

smaller image is more distant

Schemas

Concepts or mental frameworks that organize and interpret information.

Selective/focused attention

concentrating on/prioritizing certain elements in the environment

selective inattention / inattentional blindness

the ability to purposefully block out all but one bit of sensory input

sensory adaptation

diminished sensitivity as a consequence of constant stimulation

shape constancy

perceiving the same shape for objects, even if retinal image changes

signal detection theory

theory regarding how stimuli are detected under different conditions

size constancy

the tendency to interpret an object as always being the same actual size, regardless of its distance

sublimal perception

Perception below the threshold of awareness.

texture gradient

the tendency for textured surfaces to appear to become smaller and finer as distance from the viewer increases

top-down processing

a progression from the whole to the elements

David Hubel

sensation and perception - discovered feature detectors

Ernst Weber

1795-1878; Field: perception; Contributions: just-noticeable-difference (JND) that eventually becomes Weber's law; Studies: 1st study on JND

Gustav Fechner

1801-1887; Field: perception; Contributions: stated that the magnitude of a sensory experience is proportionate to the \# of JND's that the stimulus causing the experiences above the absolute threshold

Torsten Wiesel

Along with David Hubel discovered feature detector groups of neurons in the visual cortex that respond to different types of visual images

Sensation

process by which our brain and nervous system receive input from the environment through our five senses

Transduction

transforms one form of energy into another

Wavelength

distance from one wave peak to the next

Intensity

amount of energy measured by amplitude or height

Photoreceptor

(light receptor) cells that transduce light energy into electrochemical energy (nerve impulses)

Hue

the color we experience

Visible Spectrum

band of wavelengths that we can see

Cornea

transparent, convex structure that covers the front part of the eye; bends light towards center of eyeball

Iris

colored part of the eye, muscle that adjusts by dilating and constricting

Pupil

opening in iris, black

Lens

transparent structure behind the pupil that is curved and flexible and changes its curvature to help focus images

Aqueous Humor

behind the pupil and iris; chamber that is filled with this

Vitreous Humor

jellylike fluid called this

Retina

light-sensitive layer at the back of the eye

Visual Accommodation

before passing through the retina, the lens flips an image and focuses the inverted image

Rods

photoreceptors that detect black/white/gray and work in very dim light for night vision

Cones

photoreceptors the function only in bright light

Fovea

central point of the retina and a part of the a part of the macula, which has multiple structures to ensure focused vision

Optic Nerves

nerves that send signals from the eyes to the brain

Optic Chiasm

some of the fibers from each optic nerve cross into the opposite side of the brain (the thalamus) at this

Peripheral Vision

the eyes ability to see things on either side of our field of vision when looking straight ahead

Blind Spot

the point where the disc where the ganglion cells meet at the back of the eye is a hole in the retina; where there are no photoreceptors

Saccade

reflexive, rapid movement from side to side, keeps different neurons firing and helps fill in the missing info created by the blind spot; reading

Dark Adaptaion

ability to adapt to quickly darkening conditions such as when we go from daylight into a dark movie theatre

Feature Detectors

thousands of specialized neurons react to the strength of visual stimuli, responding to shapes, angles, edges, lines, and movement in our field of vision

Parallel Processing

the ability of the brain to do many things at once

Trichromatic (Young-Helmholtz) Theory

earliest theory about why we can see color only within the visible spectrum

Opponent-Process Theory

the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green

Afterimage

the visual sensation that occurs after the original stimulus has been removed

Color BLindness

the inability to perceive color differences

Audition

biological process by which our ears process sound waves

SOund Waves

vibrations of molecules that travel through the air

Amplitude

affects the psychological quality of loudness (sound pressure or intensity)-how much pressure is being forced through the air

Pitch

a sound's note

Frequency

number of wavelength cycles in a unit of time (the number of wavelengths per second) measured in hertz

Pinna

funky-shaped outer ear

Auditory Canal

ear canal

Tympanic Membrane

eardrum

Middle ear

the chamber between the eardrum and cochlea containing 3 tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window

Malleus

hammer

Incus

anvil

Stapes

stirrup

Oval Window

membrane at the enterance to the cochlea through which the ossicles transmit vibrations

Inner ear

where stapes meet oval window, part of the snail-shaped organ called the cochlea

Cochlea

snail shaped organ-resonates different sounds to different locations

Auditory Nerve

hair cells convert vibrations into nerve impulses and send them to the auditory nerve

Place Theory

higher and lower tones excite specific areas of the cochlea along the basilar membrane, each location resounding differently to different pitches

Frequency Theory

as a pitch rises, the entire basilar membrane vibrates at that frequency, with nerve impulses that correspond with the pitch frequency traveling up the auditory nerve enabling us to perceive pitch in a kind of frequency coding

Conductive Hearing Loss

a condition in which there is a poor transfer of sounds from the tympanic membrane of the inner ear -common as people get older