SlEEp

Age Trends in Sleep People in different stages of life need different amounts of sleep! Newborns sleep about 16 hours of the day Infants spend about 50% of their sleep in REM Declines to about 30% in the first year Adults spend about 20% of their sleep in REM

Age trends in sleep Over the years, REM sleep stays relatively stable but the percentage of time of slow wave sleep declines and the percentage of time in stage 1 increases-with trends stronger in men than women Average amount of total sleep declines with age (but old people tend to sleep more)

Culture and Sleep Relatively modest differences in sleep across culture in sleeping time and the amount of time it takes them to get to bed Cultural differences in sleeping are largely limited to co-sleeping and siestas

Neural Bases of Sleep Waking and sleep tends to be regulated by subcortical structures deep within the brain Reticular formation is important Ascending reticular activating system- consists of the afferent fibers running through the reticular formation that influence physiological arousal Electrical stimulation along these pathways produces arousal and alertness Pons and areas in the midbrain appear to deal with REM sleep Medulla, thalamus, hypothalamus and limbic system are implicated in the control of sleep Serotonin, GABA, norepinephrine, dopamine, and acetycholine all participate as well

Sleep Deprivation Effects of sleep deprivation depends on the amount of sleep lost as well as the activity at hand Negative effects are likely when the task is long, monotonous , difficult, or when patients are asked to restrict their sleep over several nights

Sleep Deprivation- ever get the munchies? Makes you fatter! Sleep deprivation increases ghrelin, a hunger arousing hormone and decreases its hunger suppressing partner, leptin Increases cortisol, a stress hormone that stimulates the body to make fat If you sleep more, you eat less! First year 4, not the freshman 15 

Dangers of Deprivation Contributes to errors in medical treatment by physicians in training Transportation mishaps 20% of motor vehicle accidents Chernobyl, Three Mile Island, and the Challenger disaster 2013 Asiana Airlines accident at 3 AM occurred after a 10 hr flight from Seoul Drowsiness costs the US over $56 billion annually, 52 million work days, and over 24,000 deaths In Canada and the United States, accidents immediately increase after the time changes in daylight savings time (when it shortens sleep)

Selective Deprivation People rebound after REM and SWS deprivation= we need these!

Sleep disorders

Insomnia Chronic problems in getting adequate sleep Difficulty in falling asleep initially Difficulty in remaining asleep Persistent in early morning awakening Associated with daytime fatigue, impaired functioning, elevated risk for accidents, reduced productivity, absenteeism in work, depression, and increased health problems

Insomnia 34-35% of adults report problems with insomnia 15-17% suffer from severe insomnia Excessive anxiety and tension Possible side effect of emotional problems Health issues-back pain, ulcers, asthma

Causes Excessive anxiety and tension Possible side effect of emotional problems Health issues-back pain, ulcers, asthma Certain drugs

Treatment Sedative drugs Benzodiazepine medications Over prescription 5-15% of adults use them regularly Hangover effects Less impactful, escalating dependency (tolerance) AMBIEN

Narcolepsy Sudden and irresistible onsets of sleep during normal waking hours Wakefulness to REM for 10-20 minutes 0.05% of the population genetics

Sleep Apnea Frequent, reflexive gasping for air that awakens a person and disrupts their sleep Stop breathing for a minimum of 10 seconds 2% of women 4% of the men

Nightmares Anxiety arousing dreams that lead to awakening, usually from REM sleep Connection between nightmare distress and depression and neuroticism

Night Terrors Abrupt awakenings from NREM sleep accompanied by intense automatic arousal and feelings of panic Stage 4 sleep Cant recall a dream but a specific frightening image

Somnambulism NEVER FORGET 10/21/14 Sleepwalking, occurs when a person arises and wanders about while remaining asleep First 2 hours of sleep 15 seconds to 30 minutes Genetic predisposition NEVER FORGET 10/21/14