Chapter 4: Sleep
insomnia
-difficulty falling or staying asleep -can be caused by stress, anxiety, medical problems, poor sleep environment, noisy or restless partners, and schedule changes --distress over inability to fall asleep contributes --improved sleep habits and exercise have been shown to improve sleep quality for chronic insomnia
what is sleep?
-period of rest and recovery from the demands of wakefulness -can be described as a state of unconsciousness or partial consciousness from which a person can be roused by stimulation -spend about a 1/3 of our lives sleeping
sleep apnea
-periods of nonbreathing during sleep -almost 40% of US population may have some form of sleep apnea, but 80-90% of cases are undiagnosed
night eating syndrome
-person eats excessively during the night while awake -repeatedly awakens during the night to eat, then eats very little during the day
sleep-related eating disorder (SRED
-person rises from bed during the night and eats and drinks while asleep -about three-quarters with it are female -person has no memory of the episode(s) and does not experience fullness or indigestion
sleep walking disorder
-person rises out of an apparently deep sleep and acts as if awake -episodes typically last less than ten minutes -may be brought on by excessive sleep deprivation, fatigue, stress, illness, excessive alcohol, and use of sedatives
what are the health effects of sleep?
-sleep is strongly associated with overall health and quality of life -restoration and growth take place during deepest stages of sleep -natural immune system moderators increase during sleep and promote resistance to viral infections -lack of sleep can cause breakdown in the body's health-promoting processes
how does sleep deprivation affect physical and mental health?
-slowed reaction time -high blood pressure, heart disease, and stroke -suppressed immune system -overweight and obesity -breast cancer -diabetes -dementia, alzheimer's, multiple sclerosis, Parkinson's disease
obstructive sleep apnea
-upper airway is obstructed during sleep -potentially dangerous or fatal -associated with high BP and increased risk of heart disease and stroke
how much sleep does the typical college student get?
6-7 hours a night on weeknights
how much sleep does an adult need?
8-9 hours
Sleep Cycles
NREM->REM1->NREM->REM2->NREM stage 3->REM3->NREM stage 2->REM 4->NREM stage 2->REM 5--->awake --cycling back and forth repeats about every 90-110 minutes until waking --children and adolescents experience large quantities of deep sleep --as people get older, high quality deep sleep decreases --women have more slow-wave sleep (NREM 3 and 4) and experience more insomnia --after each successive cycle, time spent in REM sleep doubles, lasting from 10-60 minutes at a time
multiple sleep latency test
administered as an index of daytime sleepiness, usually repeated five times during the day in a sleep clinic
central sleep apnea
brain fails to regulate the diaphragm and other breathing mechanisms correctly; rare
how does sleep deprivation affect the brain?
chronic sleep deprivation damages brain cells and impairs debris removal which accelerates brain aging
what are the consequences of insufficient REM sleep?
impairs memory and ability to learn new skills
circadian rhythm
internal daily 24-hour cycle of waking and sleeping
what is sleep deprivation?
lack of sufficient time asleep, which impairs physical, emotional, and cognitive functioning
health effects of sleep: short sleep and long sleep
short sleep: less than 7 hours; increases risk of negative outcomes long sleep: ten hours or more; no negative health conssequences
how is sleep structured?
two main states of sleep: 1. non-rapid eye movement 2. rapid eye movement NREM sleep: stage 1: relaxed, half-awake sleep stage 2: brain activity slows and movement stops stages 3 and 4: BP drops, heart rate slows, blood supply to brain minimized; stage 4 is deep sleep REM sleep: brain activity becomes more like being awake, dreams occur, and sleep paralysis occurs
continuous positive airway pressure (CPAP) machine
used to treat severe sleep apnea; mask that blows pressurized air into the patient's nose
REM rebound effect
when long sleep is possible after inadequate sleep for several nights, you will have longer and more frequent REM sleep
sleep latency
-amount of time it takes a person to fall asleep -helpful in evaluating sleep
what makes you sleep?
-circadian rhythms are maintained by the suprachiasmic nuclei (SCN) in the brain , which is like an internal biological clock that controls body temperature and levels of alertness and activity -SCN signal the release of hormones, including signaling the pineal gland to release melatoning and the pituitary gland to release growth hormone -external environmental cues such as light are also important
OTC medicines for sleep
-contains antihistamines -can cause dehydration, agitation, and constipation -rebound insomnia: insomnia occurs that is worse than before the medication was taken
sleep debt
The difference between the amount of sleep you should be getting and the amount you actually get.