AP psych: sensations and consciousness

sensation

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

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

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 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")

subliminal

below one's absolute threshold for conscious awareness

priming

the activiation, 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 (also called just noticeable difference or jnd)

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

transduction

the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret

hue

the dimension of color that is determiend by the wavelength of light; what we know as the color names blue, green, and so forth

intensity

the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave's amplitude

pupil

the adjustable opening in the center of the eye through which light enters

iris

a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

lens

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

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

acuity

the sharpness of vision

rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond

cones

retinal receptors cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions; they detect fine detail and give rise to color sensations

fovea

the central focal point in the retina, around which the eye's cones cluster

parallel processing

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

trichromatic (three-color) theory

the theory that the retina contains three different color receptors--one most sensitive to red, one to green, one to blue--which when stimulated in combination can produce the perception of any color — at the cones level

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 — how it is processed back to brain

color constancy

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

audition

the sense or act of hearing

frequency

the number of complete wavelengths that pass a point in a given time

pitch

a tone's experienced highness or lowness; depends on frequency

middle ear

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

cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

inner ear

the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs

frequency theory

in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch

conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea

sensorineural hearing loss

hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness

cochlear implant

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

gate-control theory

the theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain; the "gate" is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain

sensory interaction

the principle that one sense may influence another, as when the smell of food influences its taste

olfaction

the sense or act of smelling

kinesthesis

the system for sensing the position and movement of individual body parts

vestibular sense

the sense of body movement and position, including the sense of balance

serotonin

hormone linked to mood and depression effects mood, hunger, sleep, and arousal

endorphins

natural opiate, regulates pain perception linked to positive emotions

adrenalin

hormone that prepares body for fight or flight

oxytocin

hormone linked to social bonding and relationships

antagonist

decrease a neurotransmitters action by blocking its release

caffeine

a stimulant that blocks the neurotransmitter related to sleep and relaxation

hallucinogens

a drug that causes distortion of a person's thoughts, feelings, and perceptions

tolerance

when you take a certain drug enough that your body adapts and requires more amounts to get an effect

NREM 1

transition from wakefulness to sleep; lose response to environmental stimulus

beta waves

brain waves associated with normal waking consciousness, active thinking, problem-solving, and alertness.

k-complexes

They serve as a protective mechanism to prevent the brain from waking up, essentially filtering out minor disruptions in the environment during NREM 2

activation synthesis

a theory that proposes dreams are the brain's attempt to make sense of random neural activity during REM sleep.

narcolepsy

unstable switching between awake and asleep; people can hallucinate

accommodation

when your eye changes its curvature of the lens to focus on objects at various distances

wavelength

distance from peak of one light to the next

prosopagnosia

neurological disorder in which people cannot recognize faces despite having healthy vision and normal intelligence

volley theory

explaining how the auditory system processes sound frequencies, especially those too high for a single neuron to fire at the rate of the sound.

supertaster

more taste buds on tongue; more sensitive to certain tastes 

semicircular canals

located in the ears, associated with balance

excitatory

increases likelihood of neural firing

norepinephrine

used for arousal in fight or flight; stress and eating 

substance P

transmits pain signals from body to brain

leptin

hormone associated with eating and signaling the body that it is full

endocrine system

secrete hormones that effect stress, eating, etc

reuptake

the excess energy from a neurotransmitter is reabsorbed back into the cell

cocaine

blocks dopamine transporters from reabsorbing; stimulant

marijuana

counteracts inhibitory neurotransmitters allowing dopamine; removes short term memory collection and slows movement

addiction

dependency on a certain drug

NREM 2

marks the beginning of sleep here muscle tension, heart rate, and body temperature decrease

alpha waves

brain waves associated with a relaxed, awake state, such as during meditation or when eyes are closed.

delta waves

the slowest and highest amplitude brain waves, characteristic of the deepest stages of NREM sleep (specifically Stages 3 and 4)

consolidation theory

concept that new memories are transformed from short-term into stable, long-term memories through a process of neurobiological stabilization.

REM behavior disorder

muscles are active during REM; ppl will act out their dreams

blind spot

when the optic nerve leaves eye; no receptor cells are located there

ganglion cells

neurons in the retina that are the final output cells of the eye, transmitting visual information to the brain via the optic nerve.

pheromones

chemical signals released by animals that influence the behavior and physiology of other members of the same species.

kinesthesis

the sense of your body;s position, movement, and action

inhibitory

chemical messengers that reduce the likelihood of neuron firing

glutamate

carries signals between nerve cells; role in learning, memory, cognition, and mood regulation

acetylcholine

enables muscles action; related by motor neurons to activate skeletal neurons

ghrelin

hormone produced by the stomach; increases food intake, and makes you hungry

pituitary gland

gland that releases hormones that regulate growth and control other endocrine glands

reuptake inhibitor

stops the absorption of excess chemicals back into cell

depressants

drugs that reduce arousal and stimulation in certain areas of the brain by slowing down bodily functions and neural activity

opioids

drugs used for treating pain

withdrawal

symptoms that develop when a person who has been regularly using a substance stops or reduces their use; these symptoms cause significant distress 

NREM 3

deepest stage of non REM sleep, also known as deep sleep; physical restoration and tissue repair

theta waves

brain waves associated with the transitional state between wakefulness and sleep, deep relaxation, and states of creativity and memory processing. (REM)

paradoxical sleep

another terms for REM

physical restoration

process of the body repairing during sleep

sleep apnea

sleep disorder where breathing repeatedly stops and starts during sleep

absolute threshold

minimum intensity of a stimulus that can be detected by an individual 50% of the time

optic nerve

nerve fibers that carries visual information from the retina to the brain for processing

amplitudes

height or intensity of a wave

dichromatism 

type of partial color blindness where a person has only two function types of cone cells in the eyes — instead of three

sound localization

process of determining the origin of a sound

olfactory system

responsible for sense of smell through the nose

phantom limb sensation

felling that a missing body part is still present