IB SL PSYCH FINAL EXAMS

melatonin

A hormone produced mainly by the pineal gland that is implicated in the initiation of sleep and in the regulation of the sleep-wake cycle.

addiction

A state of psychological or physical dependence (or both) on the use of alcohol or other drugs.

agonist

A drug that increases the effects of a neurotransmitter's action by either mimicking the neurotransmitter or allowing more to be released.

alcohol

A depressant that disrupts memory formation during REM sleep and lowers inhibition.

antagonist

A drug that inhibits or blocks a neurotransmitter's action.

caffeine

A stimulant which can increase alertness and wakefulness but also produce anxiety, restlessness, and insomnia in high doses.

cocaine

A powerful and addictive stimulant which produces temporarily increased alertness and euphoria. Blocks dopamine reuptake.

depressants

Drugs that reduce neural activity and slow body functions.

hallucinogens

Psychedelic ('mind-manifesting') drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input.

heroin

As a nervous system depressant, this opioid can produce a rush of euphoria, confidence, and energy, as well as cardiovascular stress, suspiciousness, and a depressive crash.

marijuana

A mild hallucinogen that produces a 'high' often characterized by feelings of euphoria, a sense of well-being, and swings in mood from gaiety to relaxation; may also cause feelings of anxiety and paranoia.

opioids

Opium and its derivatives, such as morphine and heroin; they depress neural activity, temporarily lessening pain and anxiety.

psychoactive drugs

Any drug that has significant effects on psychological processes, such as thinking, perception, and emotion. They include those deliberately taken to produce an altered state of consciousness and therapeutic agents designed to alleviate a mental condition.

stimulants

Drugs that excite neural activity and speed up body functions.

tolerance

The diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drug's effect.

withdrawal

The discomfort and distress that follow discontinuing an addictive drug or behavior.

activation synthesis

Theory that dreams reflect inputs from brain activation originating in the pons, which the forebrain then attempts to weave into a story.

circadian rhythm

The biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle.

consciousness

Our awareness of ourselves and our environment.

consolidation theory

The theory that sleep aids memory consolidation. Sleep also helps to restore and rebuild the experiences and memories of our day.

hypnogogic sensations

Bizarre experiences, such as jerking or a feeling of falling or floating weightlessly, while transitioning to sleep.

insomnia

Recurring problems in falling or staying asleep.

jet lag

A disruption of circadian rhythms due to crossing time zones.

narcolepsy

A sleep disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep, often at inopportune times.

NREM sleep

Non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep.

NREM stage 1

The initial stage of NREM sleep, which is characterized by low-amplitude brain waves (4-6 Hz) of irregular frequency, a slow heart rate, and reduced muscle tension.

NREM stage 2

A stage of NREM sleep that is defined by regular bursts of waves of about 15 Hz that progressively increase and then decrease in amplitude. Stage 2 is half of your night's sleep.

NREM stage 3

During this slow wave sleep, which lasts for about 30 minutes your brain emits slow delta waves; deep sleep; where somnambulism is most likely to occur.

paradoxical sleep

Although the brain is quite active during REM sleep, consuming large amounts of energy, the body remains completely inactive. In addition, the brain waves during REM sleep are reminiscent of the brain waves demonstrated when someone is awake and alert.

REM rebound

The tendency for REM sleep to increase following REM sleep deprivation.

REM sleep

Rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur.

REM sleep behavior disorder

A sleep disorder in which normal REM paralysis does not occur; instead, twitching, talking, or even kicking or punching may occur, often acting out one's dream.

shift work

Work scheduled during the swing shift (usually 4 p.m. to 12 a.m.) or night shift (12 a.m. to 8 a.m.).

sleep apnea

A sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings.

somnambulism

A sleep disorder characterized by persistent incidents of complex motor activity during slow-wave NREM sleep.

sleep/wake cycle

This is a component of circadian rhythm.

ghrelin

Hunger arousing hormone that is increased with a lack of sleep.

leptin

Hunger suppressing hormone that is decreased when sleep deprived causing weight gain.

Wish fulfillment theory

Dreams are access to our unconscious mind (our wishes and anxieties).

Manifest content

The remembered storyline/plot of a dream; what actually happens in a dream.

Latent content

The underlying meaning of a dream.

Information processing theory

Dreams act to sort out and understand the memories that you experience that day. (evidence: REM sleep increases after stressful events).

Activation synthesis theory

Dreams are a way to make sense of random neural firing: your brain is 'pooping'.

absolute threshold

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

accommodation

The process by which the focus of the eye is changed to allow near or distant objects to form sharp images on the retina.

afterimages

A visual image that persists after a stimulus is removed.

amplitude

The height of a wave as measured from the highest point on the wave (peak or crest) to the lowest point on the wave (trough).

bitter

The unpleasant taste evoked by foods like coffee, spinach, and brussels sprouts; natural selection may contribute to a predisposition to find these tastes unpleasant, especially during early childhood, as bitter-tasting substances in the natural environment are often toxic.

blindspot

The point at which the optic nerve leaves the eye, creating an area in which no visual information can be detected because no receptor cells are located there.

conduction deafness

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

cones

Retinal receptor cells that are concentrated near the center of the retina and that function in daylight and in well-lit conditions.

dichromatism

Partial color blindness in which the eye contains only two types of cone photopigment instead of the typical three.

farsightedness

A refractive error due to an abnormally short eyeball, which causes the image of close objects to be blurred because the focal point of one or both eyes lies behind, rather than on, the retina.

frequency theory

The rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch.

ganglion cells

The last layer of photoreceptors within the retina that sends signals to the brain resulting from visual stimulation.

gate control theory

Spinal cord contains a neurological 'gate' that blocks pain signals and allows them to pass on to the brain.

gustation

The sense of taste.

just-noticeable difference

The minimum distinction between two stimuli required for detection 50% of the time.

kinesthesis

Also known as proprioception, this is the sense of the location of body parts in relation to the ground and each other.

lens

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

loudness

The subjective magnitude of sound, determined primarily by intensity but also affected by other physical properties, such as frequency, spectral configuration, and duration.

medium tasters

Average ability tasters.

monochromatism

A partial color blindness in which the eye contains only one type of cone photopigment instead of the typical three; everything appears in various shades of a single color.

nearsightedness

The retinal image is blurred because the focal point of one or both eyes lies in front of, rather than on, the retina; this allows you to see what is near you, but struggles with items far away.

nontasters

Someone who has less taste perception; they usually require more seasoning to make food taste good, except for salt, and have a clear preference for high-fat, sweeter foods.

oleogustus

The unique taste of fat, recently identified as separate from other distinct tastes.

olfactory system

The sense of smell, involving stimulation of receptor cells in the olfactory epithelium by airborne volatile substances called odorants.

opponent-process theory

Opposing retinal processes (red-green, yellow-blue, white-black) enable color vision.

phantom limb

The feeling that an amputated limb is still present, often manifested as a tingling or, occasionally, painful sensation in the area of the missing limb.

pheromones

Olfactory chemical messages released outside the body by members of a species that influence the behavior of other members of the species.

photoreceptors

Visual receptors in the eye, specifically rods and cones.

pitch

A tone's experienced highness or lowness; depends on frequency.

pitch perception

The ability to distinguish between tones played at differing frequencies.

place theory

Links the pitch we hear with the place where the cochlea's membrane is stimulated.

prosopagnosia

Inability to recognize familiar faces.

retina

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

rods

Retinal receptors that detect black, white, and gray; necessary for peripheral vision and twilight vision.

salty

The unique taste evoked by sodium chloride or lithium chloride, or other sodium and lithium salts.

semicircular canals

A set of three looped tubular channels in the inner ear that detect movements of the head and provide the sense of dynamic equilibrium essential for maintaining balance.

sensation

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

sensorineural deafness

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

sensory adaptation

Diminished sensitivity as a consequence of constant stimulation.

sensory interaction

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

sound localization

The ability to identify the position and changes in position of sound sources based on acoustic information.

sour

The taste elicited by acid; acids are involved in many physiological processes and also characterize unripe or spoiled foods.

supertaster

An individual whose perception of taste sensations is the most intense; about 25% of the population.

sweet

The pleasurable taste associated with sugars, an immediate source of energy.

synesthesia

When one kind of sensory stimulus evokes the subjective experience of another.

taste receptors

Proteins that recognize taste stimuli.

thalamus

The brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla - all senses but smell are processed here.

transduction

Conversion of one form of energy into another - transferring stimulus energies into neural impulses our brains can interpret. (ex.: light energy to vision // chemical energy to smell and taste // sound waves to sound)

trichromatic theory

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

umami

Denoting the taste of foods rich in protein (e.g., meats, fish, some vegetables, cheeses), as represented by the taste of monosodium glutamate, which is used primarily to enhance other flavors. Umami is sometimes described as 'savory.' [Japanese, 'delicious']

vestibular sense

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

visual nerve

Carries neural impulses from the eye to the brain.

volley theory

This theory states that groups of neurons of the auditory system respond to a sound by firing action potentials slightly out of phase with one another so that when combined, a greater frequency of sound can be encoded and sent to the brain to be analyzed.

warm/cold receptors

Thermoreceptors; receptors on our skin that are either sensitive to warmth or to cold; Cold receptors are free nerve endings with thin myelinated fibers, whereas the warm receptors are free nerve endings with unmyelinated axons with low conduction speeds.

wavelength

The distance between two corresponding parts of a wave; determines color within vision and pitch within sounds.

Weber's law

The principle that, to be perceived as different, two stimuli must differ by a constant percentage (rather than a constant amount)- (would you drive 10 minutes to save $20 on a meal? yes! // would you drive across town to save $100 on a $30,000 car? no!)

blindsight

A condition in which people who are blind have some spared visual capacities in the absence of any visual awareness.