Why do we sleep and dream?

Question 1

chronotype

Answer 1

Individual differences in circadian activity.

Question 1

insomnia

Answer 1

Disorder of slow-wave sleep resulting in prolonged inability to sleep.

Question 1

Zeitgeber

Answer 1

Environmental event that entrains biological rhythms: a ‘time giver.’

Question 2

circadian rhythm

Answer 2

Day-night rhythm.

Question 3

narcolepsy

Answer 3

Slow-wave sleep disorder in which a person uncontrollably falls asleep at inappropriate times.

Question 4

reticular activating system (RAS)

Answer 4

Large reticulum (mixture of cell nuclei and nerve fibers) that runs through the center of the brainstem; associated with sleep-wake behavior and behavioral arousal; often called the reticular formation.

Question 5

medial pontine reticular formation (MPRF)

Answer 5

Nucleus in the pons participating in REM sleep.

Question 6

sleep spindle

Answer 6

Brief burst of EEG activity typically occurring during NREM sleep.

Question 7

dimer

Answer 7

Two proteins combined into one.

Question 8

peribrachial area

Answer 8

Cholinergic nucleus in the dorsal brainstem having a role in REM sleep behaviors; projects to medial pontine reticulum.

Question 9

melatonin

Answer 9

Hormone secreted by the pineal gland during the dark phase of the day-night cycle; influences daily and seasonal biorhythms.

Question 9

metabolic syndrome

Answer 9

Combination of medical disorders, including obesity and insulin abnormalities, that collectively increase the risk of developing cardiovascular disease and diabetes.

Question 9

NREM (non-REM) sleep

Answer 9

Slow-wave sleep associated with delta rhythms.

Question 10

microsleep

Answer 10

Brief period of sleep lasting a second or so.

Question 12

sleep paralysis

Answer 12

Inability to move during deep sleep owing to the brain’s inhibition of motor neurons.

Question 13

biorhythm

Answer 13

Inherent timing mechanism that controls or initiates various biological processes.

Question 13

diurnal animal

Answer 13

Organism that is active chiefly during daylight.

Question 14

light pollution

Answer 14

Exposure to artifical light that changes activity patterns and so distrupts circadian rhythms.

Question 15

reconsolidation

Answer 15

The process of restabilizing a memory trace after the memory is revisited.

Question 15

retinohypothalamic tract

Answer 15

Neural route formed by axons of photosensitive retinal ganglion cells from the retina to the suprachiasmatic nucleus; allows light to entrain the rhythmic activity of the SCN.

Question 16

basic rest-activity cycle (BRAC)

Answer 16

Recurring cycle of temporal packets, about 90-minute periods in humans, during which an animal’s level of arousal waxes and wanes.

Question 18

delta (d) rhythm

Answer 18

Slow brain-wave activity pattern associated with deep sleep.

Question 20

jet lag

Answer 20

Fatigue and disorientation resulting from rapid travel through time zones and exposure to a changed light-dark cycle.

Question 21

place cell

Answer 21

Hippocampal neurons maximally responsive to specific locations in the world.

Question 22

period

Answer 22

Time required to complete a cycle of activity.

Question 24

entrain

Answer 24

Determine or modify the period of a biorhythm.

Question 25

free-running rhythm

Answer 25

Rhythm of the body's own devising in the absence of all external cues.

Question 26

hypnogogic hallucination

Answer 26

Dreamlike event at the beginning of sleep or while a person is in a state of cataplexy.

Question 28

beta (b) rhythm

Answer 28

Fast brain-wave activity pattern associated with a waking EEG.

Question 29

cataplexy

Answer 29

Form of narcolepsy linked to strong emotional stimulation in which an animal loses all muscle activity or tone, as if in REM sleep, while awake.

Question 30

biological clock

Answer 30

Neural system that times behavior.

Question 31

drug-dependency insomnia

Answer 31

Condition resulting from continuous use of 'sleeping pills'; drug tolerance also results in deprivation of either REM or NREM sleep, leading the user to increase the drug dosage.

Question 32

coma

Answer 32

Prolonged state of deep unconsciousness resembling sleep.

Question 33

REM sleep

Answer 33

Fast brain-wave pattern displayed by the neocortical EEG record during sleep.

Question 35

consolidation

Answer 35

The process of stabilizing a memory trace after learning.

Question 36

suprachiasmatic nucleus (SCN)

Answer 36

Master biological clock, located in the hypothalmus just above the optic chiasm.

Question 37

sleep apnea

Answer 37

Inability to breathe during sleep; person has to wake up to breathe.

Question 38

slow-wave sleep

Answer 38

NREM sleep.

Question 39

atonia

Answer 39

No tone; condition of complete muscle inactivity produced by the inhibition of motor neurons.

Question 40

K-complex

Answer 40

Sharp, high-amplitude EEG wave occurring during NREM sleep.