Circadian rhythm
the physical, mental, and behavioral changes an organism experiences over a 24-hour cycle
dreams
a series of thoughts, images, and sensations occurring in a person's mind during sleep.
Electroencephalograph
a test that measures electrical activity in the brain using small, metal discs (electrodes) attached to the scalp
Hypersomnia
Excessive sleepiness can have causes that aren't due to underlying disease.
Insomnia
a sleep disorder in which you have trouble falling and/or staying asleep
Melatonin
Melatonin is a hormone that your brain produces in response to darkness
Napping
sleep lightly or briefly, especially during the day
Narcolepsy
a chronic neurological disorder that affects the brain's ability to control sleep-wake cycles
Night Terrors
The cause is unknown but night terrors are often triggered by fever, lack of sleep or periods of emotional tension, stress or conflict
Nightmares
a frightening or unpleasant dream.
Parasomnia
a sleep disorder that involves unusual and undesirable physical events or experiences that disrupt your sleep
Restless Legs Syndrome
a nervous system problem that causes you to feel an unstoppable urge to get up and pace or walk
Sleep
a condition of body and mind that typically recurs for several hours every night, in which the eyes are closed, the postural muscles relaxed, the activity of the brain altered, and consciousness of the surroundings practically suspended.
Sleep apnea
Anything that could narrow your airway such as obesity, large tonsils, or changes in your hormone levels
Sleep deprivation
occurs when an individual fails to get the amount of sleep that they need
Sleep paralysis
Sleep paralysis refers to the phenomenon in which resumption of consciousness occurs while muscle atonia of REM (rapid eye movement) sleep is maintained, leading to intense fear and apprehension in the patient as the patient lies awake without the ability to use any part of their body.
Sleep study
painless tests that measure how well you sleep and how your body responds to sleep problems
Snoring
the hoarse or harsh sound that occurs when air flows past relaxed tissues in your throat, causing the tissues to vibrate as you breathe
Stage 1 (Non-REM) sleep
the first sleep stage you enter when nodding off
Stage 2 (Non-REM) sleep
sleep are considered light sleep
Stage 3 (Non-REM) sleep
deep sleep
Stage 4 (Non-REM) sleep
Deepest Non-REM Sleep
Somnambulism
sleepwalking
Wakefulness
the condition of not sleeping or being unable to sleep