Sleep: The Final Frontier By: Mark Kennedy Paul Mendola Kristina Petersen

Sleep and Biological Rhythms ●Biological rhythms- periodic physiological fluctuations in the body o Includes the rise and fall of hormones an accelerated and decelerated cycles of brain activity o Can Influence our behavior o Controlled by biological clocks

Circadian Rhythms ●Circadian rhythms- daily behavioral or physiological cycles o sleep/wake cycle o body temperature o blood pressure o blood sugar level The body monitors the change from day to night by means of the suprachiasmatic nucleus (SCN)

Desynchronizing and Resetting ●Biological clocks can become desynchronized, or thrown off their regular schedules o jet travel o changing work shifts o insomnia

Why do we need sleep?

Theories on the Need for Sleep ●Evolutionary Perspective - Animals needed to protect themselves at night ●Conserve Energy - Conserve calories, Darkness is dangerous ●Restorative - Sleep restores/replenishes and rebuilds the brain and body ●Brain Plasticity - Cerebral cortex can strengthen memory associations

Sleep Deprivation (You probably are Sleep Deprived)

Effects of Chronic Sleep Deprivation ●Humans need 8 hours a night ●Increased Stress and anxiety ●Trouble paying attention or solving problems ●Sleep deprivation influences moral judgement ●Exhaustion snowballs out of control ●Weakened immune system

Why don’t we get enough sleep?

Stressors for students Homework

Stressors for students Boring Teachers Disappointed Parents

Stressors for students Band/Choir Money

Stressors for students Hilliard Davidson Cross Country Nuclear WarTests Sports B+ “My life is over!”

Stages of Wakefulness and Sleep Wakefulness Stages- When awake, EEG patterns exhibit two types of waves: beta and alpha. -Beta waves reflect concentration and alertness >waves are highest in frequency and lowest in amplitude >more desynchronous (do not form a consistent pattern) -Alpha waves are associated with relaxation or drowsiness >brain waves slow down and increase in amplitude >synchronous waves (regular) The 5 stages of sleep are differentiated by the types of wave patterns detected with an EEG.

Stages of Wakefulness and Sleep Cont. Stages 1-4 Stage 1- characterized by drowsy sleep. May experience sudden muscle movements called myoclonic jerks. > theta waves present in EEG, slower in frequency and greater in amplitude Stage 2- muscle activity decreases and person no longer consciously aware of the environment. >theta waves continue but interspersed with sleep spindles. These involve sudden increase in wave frequency. Stage 3&4- characterized by delta waves, the slowest and highest amplitude waves. >stages referred to as delta sleep >stage when bedwetting (children), sleepwalking, and sleep talking occur

Stages of Wakefulness and Sleep Cont. REM (rapid eye movement) sleep- An active stage of sleep during which dreaming occurs -shows fast waves similar to those of relaxed wakefulness -sleepers eyeballs move up and down from left to right -Non-REM sleep is characterized by lack of rapid eye movement and little dreaming -The longer the period of REM sleep, the more likely you will dream

Sleep Cycling Through the Night -The 5 stages of sleep make up a normal sleep cycle > one cycle lasts up to minutes -Amount of deep sleep is much greater in the first half of a nights sleep than in the second half -During a normal night of sleep individuals will spend about 60% of sleep in light sleep, 20% in deep sleep, and 20% in REM sleep

Sleep Throughout Life and the Brain -As children age their sleep patterns change - During adolescence, the brain and cerebral cortex is continuing to develop >their need for sleep may be linked to this development -Adolescents biological clocks undergo change as they age, delaying their period of wakefulness by approx. an hour -Sleep patterns also change in adults (40s and 50s) and late adults (60s and older) > go to bed earlier and wake earlier -Important neurotransmitters involved in sleep: Serotonin, norepinephrine and acetylcholine -As sleep begins, levels of neurotransmitters sent to forebrain start dropping, until they reach their lowest levels during stage 4 -REM sleep initiated by rise in acetylcholine (activates cerebral cortex) >Ends by rise of serotonin and norepinephrine

Sleep Disorders

Insomnia Narcolepsy Sleepwalking Nightmares Night Terrors Sleep Apnea

Insomnia - Inability to sleep, common among women, older adults, and people who are thin, stressed, or depressed. Good sleep habits and sleeping pills can help.

Sleepwalking - Occurs at deepest stages of sleep (Stages 3 and 4) - Sleep Talking Narcolepsy - Sudden uncontrollable urge to sleep. Can happen while standing or talking. Involves problems with the thalamus and amygdala Sleepwalking and Narcolepsy

Sleep Apnea ●Stopped breathing because the windpipe fails to open ●Affects 12 million Americans ●More frequent among obese individuals ●Loud snoring then silence (annoying) ●Infants can die suddenly

Nightmares and Night Terrors Nightmares - Frightening dream, perceived threat, Nightmares peak at age 3 to 6. Nightmares increase as stress increases. Night Terror - Sudden awakening from sleep and intense fear. Screaming, Increased heart rate, heavy perspiration, and movement. Peak at age 5 to 7.

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