AP Psychology: Unit 0, 1, 2, & 3: pt 1

Sensation

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

Sensory Receptors

sensory nerve endings that respond to stimuli

Perception

process by which our brain organizes and interprets sensory info, enabling us to recognize objects and events as meaningful

Bottom Up processing

info processing that begins w/sensory receptors and works up to the brain's integration of sensory info

Top Down Processing

info processing guided by higher level mental processes, as when we construct perceptions drawing on out experience and expectations

Transduction

conversion of one form of energy into another. In sensation, the transforming of physical energy (such as sights.sounds and smells) into neural impulses the brain can interpret

Absolute Threshold

the minimum stimulation 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 Stimuli

stimuli that are below the level of conscious awareness

Priming

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

Difference Threshold

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

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

Cornea

light energy enters the eye through the _________________

Pupil

small adjustable opening that light passes through after the cornea

Iris

colored muscle that dilates or constricts in response to light intensity

Lens

the transparent structure behind the pupil that changes shape to help focus images on the retina

Accomodation

the process by which the eye's lens changes shape to focus near or far objects on the retina

Nearsightedness

occurs when lens focuses images on a point in front of the retina, you can see near objects clearly but not distant objects

Farsightedness

occurs when the lens focuses images on a point behind the retinal you see distant objects better than near objects

Retina

the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information

Cones

retinal receptor cells that are concentrated near the fovea and that function in daylight or in well-lit conditions. The cones process color and fine detail

Rods

located in the retina's outer regions and mainly activated in low-light environments. They detect shapes and movement and help eyes adapt to darkness

Optic Nerve/Blinspot

point where optic nerve leaves the eye creates a "blind spot" because no receptor cells are located there

Wavelength

distance from the peak of one light wave to the peak of the next and determines the perceived hue of light

Blue Cones

short wavelengths

Green Cones

medium wavelengths

Red Cones

long wavelengths

Amplitude

height of light or sound wave and determines intensity

Trichromatic Theory

there are 3 types of cones each most sensitive to the wavelengths of red, green, or blue. When light stimulates combos of these cones, we see other colors

Opponent Process Theory

the theory that opposing retinal processes enable color vision ("either-or" messages)

color vision deficiency (aka color blindness)

involves damage or irregularities to cones or ganglion cells

Monochromat

person who sees only shades of gray; caused by a rare form of color deficiency

Dichromat

cannot distinguish between red and green (most common) or cannot distinguish between yellow and blue (rare)

Feature deectors

nerve cells in the brain's visual cortex that respond to specific features of a stimulus, such as particular lines, shapes, angles or movement

Prosopagnosia

face blindness- disorder where a person cannot recognize faces

Amplitude of sound waves determines their ______________

loudness

Frequency of sound waves determines their ______________

pitch

Conduction Hearing Loss (aka conduction deafness)

less common form of hearing loss, caused by damage to mechanical system that conducts sound waves to cochlea

Sensorineural hearing loss (aka nerve deafness)

most common form of hearing loss, caused by damage to the cochlea's receptor cells or to the auditory nerve

causes of sensorineural hearing loss

disease, heredity/aging, toxic noise (loud music)

Cochlear Implant

a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea

Place Theory

we hear diff pitches b/c diff sound waves trigger activity at diff places along the cochlea's basilar membrane

Frequency Theory

brain reads pitch by monitoring the frequency of neural impulses traveling up the auditory nerve

Volley Theory

neural cells can alternate firing. By firing rapid succession, they can achieve a combined frequency above 1,000 waves per sec

Sound Localization

sound waves strike one ear sooner and more intense than the other

Gate Control Theory

theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain

Phantom Limb Sensations

sensations that come even when a limb is missing

Can placebo treatments (fake painkillers, fake acupuncture) help control pain?

yes

can distraction be an effective pain control technique?

yes

Kinesthesia

our movement sense-our system for sensing the position movement of individual body parts

Vestibular Sense (aka sense of equilibrium)

provides info about the position of the head and its movements (important for balance) (relies on semicircular canals and vestibular sacs)

Gustation

sense of taste

Olfaction

sense of smell

How is the olfactory system involved in our sense of taste?

most of properties that make food taste good are actually odors detected by the olfactory system

Supertasters

have more taste buds than others enabling them to experiences more intense tastes

Medium Tasters

average ability tasters

Nontasters

lower than average ability tasters

Smell (olfaction)

we smell something when molecules of a substance carried in the air pass through the mucous membrane of the upper part of the nose and bind to receptors on the dendrites of olfactory neurons

Which part of the brain is not involved with olfaction but is involved with other senses?

thalamus

Selective Attention

focusing conscious awareness on a particular stimulus

Change Blindess

failing to notice changes in the environment

Perceptual Set

a mental predisposition to perceive one thing and not another

Is perceptual set part of bottom up processing or top down processing?

Top Down

Gestalt Psychology

a psychological approach that emphasizes that we often perceive the whole rather than the sum of the parts

Figure and Ground

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

Proximity

group nearby figures togehter

Similarity

group objects according to how similar they are to each other

Closure

fill in gaps to create a complete, whole object

Depth Perception

ability to see objects in 3 dimension although the images that strike the retina are 2 dimensional: allows us to judge distance

Binocular Cues

depth cues that depend on the use of 2 eyes

Convergence

cue to nearby objects distance, enabled by the brain combining retinal images

Retinal Disparity

binocular cue for perceiving depth

Monocular Cues

depth cues available to each eye separately

Relative Clarity

more light passes through objects farther away (hazy blurry unclear) nearby objects (sharp/clear)

Relative Size

if we assume 2 objects are similar in size, most ppl perceive the one that casts the smaller retinal image as farther away

Texture Gradient

moving toward or away from an object changes our perception of its smoothness or texture

Linear Perspective

sharper the angle of convergence, the greater the percevied distance is

Interposition

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

Apparent Movement

situations where movement is visually perceived even when objects are not actually moving

Perceptual Constancy

involves perceiving objects as unchanging even as illumination and retinal images change

Perceptual constancy involves what type of processing?

top down processing

color constancy

perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths rejected by the object

Brightness Constancy

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

Relative Luminance

amount of light an object reflects relative to its surroundings

Shape Constancy

we perceive the form of familiar objects, such as the door

Size Constancy

we perceive an object as having an unchanging size, even while our distance from it varies

Sensory Interaction

principle that our senses can influence each other

Synesthesia

brain circuits for 2 or more senses become joined and the stimulation of one sense (such as hearing a sound) triggers an experience of another (such as seeing color)

Lesions

tissue destruction (occur naturally, during surgery, or experimentally)

Autopsy

Postmortem examination to determine cause of death

Brain Stimulation

scientists can stimulate different parts of the brain and observe the body's responses (electrically, chemically, or magnetically)

Electroencephalogram (EEG)

electrodes placed on the scalp measure electrical activity in neurons (shows brain waves)

CT scan

X-rays of the head generate images that may locate brain damage

MRI scan

magnetic fields and radio waves are used to provide a detailed image of soft tissues in the body, including the brain

PET scan

tracks where in the brain a temporarily radioactive form of glucose goes while the person give it performs a task

fMRI scan

measures oxygen and blood flow to brain regions by comparing continuous MRI scans: shows both structure and function of brain

3 main divisions of brain

hindbrain, midbrain, forebrain

Hindbrain consists of?

medulla, pons, cerebellum

Hindbrain Function

directs essential survival functions such as breathing, sleeping, and wakefulness, as well as coordination and balance