Sleep Flashcards
part of the brain that controls the sleep-wake cycle
Hypothalamus
the internal clock that tells people when to wake up and when to fall asleep — area within the hypothalamus
Suprachiasmatic Nucleus (SCN)
a cycle of bodily rhythm that occurs over a 24-hour period
Circadian Rhythm
brief sidesteps into sleep lasting only a few seconds
Microsleeps
theory of sleep proposing that animals and humans evolved sleep patterns to avoid predators by sleeping when predators are most active
Adaptive Theory
theory of sleep proposing that sleep is necessary to the physical health of the body and serves to replenish chemicals and repair cellular damage
Restorative Theory
any significant loss of sleep, resulting in problems in concentration and irritability
Sleep Deprivation
two kinds of sleep
Rapid Eye Movement (R; REM) Sleep
Non-Rapid Eye Movement (N; NREM) Sleep
stage of sleep in which the eyes move rapidly under the eyelids and the person is typically experiencing a dream
Rapid Eye Movement (R; REM) Sleep
any of the stages of sleep that do not include REM
Non-Rapid Eye Movement (N; NREM) Sleep
smaller and faster brain waves, typically indicating mental activity
Beta Waves
brain waves that indicate a state of relaxation or light sleep
Alpha Waves
brain waves indicating the early stages of sleep
Theta Waves
long, slow brain waves that indicate the deepest stage of sleep
Delta Waves
stages of sleep cycle repeated 4-5 times a night
N1: Light Sleep
N2: Sleep Spindles
N3: Delta Waves Roll In
R: Rapid Eye Movement
hypnogogic images or hallucination
hypnic jerk
N1: Light Sleep
the body temperature continues to drop, heart rate slows, breathing becomes more shallow and irregular, and the EEG will show the first signs of sleep spindles
N2: Sleep Spindles
the slowest and largest waves make their appearance — these waves increase during this stage from about 20 percent to more than 50 percent of total brain activity;
sleepwalking and night terrors occur in this stage;
slow-wave sleep (SWS)
N3: Delta Waves Roll In
the sleeping person will go back up through N2 and then into a stage in which body temperature increases to near-waking levels, the eyes move rapidly under the eyelids, the heart beats much faster, and brain waves resemble beta waves
R: Rapid Eye Movement
the inability of the voluntary muscles to move during REM sleep
Sleep Paralysis
increased amounts of REM sleep after being deprived of REM sleep on earlier nights
REM Rebound
bad dreams occurring during REM sleep
Nightmares
a rare disorder in which the mechanism that blocks the movement of the voluntary muscles fails, allowing the person to thrash around and even get up and act out nightmares
REM Behavior Disorder (RBD)
relatively rare disorder in which the person experiences extreme fear and screams or runs around during deep sleep without waking fully
Night Terrors
