Ch 14: Sleep, Dreaming, & Circadian Rhythms

What is a risk of sedative/hypnotic use?

tolerance and dependence with chronic use, next day drowsiness and risk for accidents, memory impairment

Alpha waves EEG

the relatively slow brain waves of a relaxed, awake state

EEG (electroencephalogram)

An amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp.

EOG (electrooculogram)

this measures eye movements

EMG (electromyogram)

this measures muscle tension

Stage 1 Sleep

low voltage, fast activity

Stage 2 Sleep

K complexes and sleep spindles

Stage 3 sleep

delta waves are predominated

REM (emergent stage 1)

low voltage, fast activity, eliminated core muscle tone, rapid eye movement

Cataplexy

A sudden loss of voluntary muscle strength and control that is usually triggered by an intense emotion.

Narcolepsy

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

sleep apnea

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

Insomnia

recurring problems in falling or staying asleep

nocturnal myoclonus

jerking of the limbs that can occur normally as a person is falling asleep

REM sleep without atonia

REM sleep without inhibition of motor movements

somnambulism

sleepwalking

preoptic area of the hypothalamus

Sleep requires activation of this brain region, which inhibits waking-on neurons in the brain stem

posterior hypothalamus

promotes wakefulness

suprachiasmatic nucleus (SCN)

Found in the hypothalamus just above the optic chiasm, this structure regulates the circadian timing of the sleep-wake cycle.

circadian rhythm

the biological clock; regular bodily rhythms that occur on a 24-hour cycle

REM rebound

the tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM sleep)

beta waves

smaller and faster brain waves, typically indicating mental activity, 13-30Hz

alpha waves

the relatively slow brain waves of a relaxed, awake state

delta waves

the large, slow brain waves associated with deep sleep

theta waves

brain waves indicating the early stages of sleep

gamma waves

pattern of brain activity that signals that a person is processing sensory input

A free-running circadian rhythm runs

in the absence of external time cues

Zeitgeber (time giver)

External cue that synchronizes or helps entrain (determine or modify) an organism's internal clock

REM sleep

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 minor twitches) but other body systems are active.

People with narcolepsy have reduced levels of this neurochemical

orexin

recuperation theories

sleep is needed to restore homeostasis

Adaption theories

these kinds of theories argue that sleep is tailored to the way an animal makes a living

cognitive theories

Ideas about how people process information, think, and learn.

Hypnotics

short term sleep problems, GABA-A agonists, benzodiazepines, risk of dependence, decreased SWS and memory impairment

Antihypnotics (stimulants)

Narcolepsy, amphetamines, appetite suppression, anxiety, abuse

Chronobiotics

melatonin, promotes sleep, effects are inconsistent, synthesized in pineal gland