Unit 2: Part 2A: Sleep Theories

Question 1

Circadian Rhythm

Answer 1

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

Question 2

REM Sleep

Answer 2

rapid eye movement sleep; a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for the minor twitches) but other body systems are active.

Question 3

Alpha Waves

Answer 3

the relatively slow brain waves of a relaxed, awake state

Question 4

sleep

Answer 4

periodic, natural loss of consciousness – as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation.

Question 5

hallucinations

Answer 5

false sensory experiences, such as seeing something in the absence of an external visual stimulus.

Question 6

delta waves

Answer 6

the large, slow brain waves associated with deep sleep

Question 7

NREM

Answer 7

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

Question 8

Suprachiasmatic Nucleus

Answer 8

a pair of cell clusters in the hypothalamus that controls circadian rhythm. In response to light, the SCN causes the Pineal gland to adjust melatonin production, thus modifying our feelings of sleepiness.

Question 9

hypnagogic sensations

Answer 9

life-like hallucinations that occur shortly after falling asleep; usually sensation of falling or floating

Question 10

sleep spindles

Answer 10

short bursts of brain waves detected in stage 2 sleep

Question 11

sleep paralysis

Answer 11

state of being unable to move just after falling asleep or right before waking up

Question 12

paradoxical sleep

Answer 12

The type of sleep encountered during REM when internally, the brain and body are active; while externally, the body appears calm and inactive