Sleep and Dreams Flashcards
Circadian Rhythms
occur on a 24-hour cycle and include sleep and wakefulness.
Controlled by the hypothalamus, specifically the suprachiasmatic nucleus (SCN)
- receives input from the eyes & is especially
sensitive to the light-dark cycles of day and night
- light signals the SCN to tell the pineal gland to
stop the release of melatonin…in darkness SCN no
longer sends messages, increasing melatonin
levels and sleepiness
W= wakefulness
R = REM Sleep
N= NREM sleep stage
Sleep Stage 1
just drifting to sleep, may experience fantastic images
and/or auditory hallucinations, a mix of alpha and theta waves
Sleep Stage 2
more relaxed, clearly asleep and sleep spindles occur
Sleep Stage 3
deepest sleep, hard to awaken… only occurs during the first few cycles of the night, characterized by large delta waves
Sleep Spindles
short bursts of brain activity
REM Sleep – Paradoxical Sleep
After reaching the deepest stage (3), the sleep cycle starts moving backward toward stage 1. Although still asleep, the brain engages in low amplitude, fast, and regular beta waves, much like an awake-aroused state.
REM sleep is characterized by rapid eye movement, which indicates the person having dreams.
REM is considered Paradoxical sleep because the brain is almost as active as being awake, but the body is paralyzed.
Sleep Theories - Sleep Protects
Sleeping in the darkness when predators loom kept our ancestors out of harm’s way.
Sleep Theories- Sleep Recuperates
Sleep helps restore and repair brain (and body) tissue.
Sleep Theories - Sleep Helps Remembering
Sleep restores and rebuilds our fading memories.
Sleep Theories - Sleep and Growth
During sleep, the pituitary gland releases growth hormones. Older people release less of this hormone
and sleep less.
Sleep Disorders - Insomnia
difficulty falling asleep or staying asleep
Sleep Disorders - Narcolepsy
overpowering urge to fall asleep that may occur while talking or standing up.
Experience sleep attacks that usually last 5 minutes or less… this can mean lapsing directly into REM sleep for some people
Sleep Disorders - Night Terrors
Sudden arousal from sleep and intense fear accompanied by physiological reactions (occurs usually during 1st sleep cycle of the night)
* Seems to be related to some fear the child has… but is not the same as a nightmare (bad dream)… just see images
* If not awakened, the child often won’t remember in the morning.
Sleep Disorders - Sleep apnea
failure to breathe when asleep
* Wake up hundreds of times a night so that they will begin
breathing again
* Treatments include weight loss and CPAP machine
Sleep Disorders - Sleep Walking
blank stare, move about in a slow/automatic manner, and may try to eat, dress, or go to the bathroom in the wrong place while still sleeping
* Occurs in stage 3
* Technical name is Somnambulism
