Chapter 4 - Sleep

Influencers of sleep

o Biological (not as significant as environmental) o Poor health o Hormonal shifts o Chronic pain o Psychological conditions individual factors: Using technology before your sleep Hunger/Food consumption Smoking - Nicotine is a stimulant! Caffeine - body is slow to get rid of caffeine (5-7 hours to eliminate 50%) Stimulant medication (Ritalin, Adderall) Alcohol - is a sedative - helps you fall asleep, but not stay asleep!

Sleep Deficit

Amount of sleep you should be getting - amount of sleep you actually get = sleep debt

Narcolepsy

A disorder in which the brain fails to regulate the sleep-wake cycle normally • Cataplexy • Sleep Paralysis • Vivid Dreams

Sleep Apnea

One or more pauses in breathing occur during sleep Last a few seconds to minutes 5 to 30 an hour

Diencephalon

"body clock" - circadian rhythm a pattern of physical and behavioral changes that follows a 24-hour cycle, in accordance with the hours of darkness and light. Includes the "hypothalamus" • Syncs with dark and light environment cues Includes the "pineal gland" • Produces the hormone melatonin

Cycles of sleep

After you first fall asleep, you progress through each of the four stages of NREM sleep. After 20-40 mins in deep sleep, you cycle back to stages 3 and 2 before entering a short phase of REM sleep. As the night continues, the REM sleep phases increases and NREM decreases. After about 4 hours, stage 4 sleep disappears.

Cerebrum

Cerebral cortex: electrical activity from this part of the brain helps us determine what stage of sleep you are in

Brain stem

Connects the brain and spinal cord includes a group of nerve cells called the reticular activating system (RAS) • Active RAS: awake • Inactive: asleep Includes the Pons • The pons sends a signal up to start dreaming (REM sleep) and down to the spinal cord to paralyze your muscles.

Insomnia

Difficulty falling asleep or staying asleep, or of waking too early, or poor-quality sleep Secondary insomnia: most common, due to behavior (like substance abuse), or due to another medical condition Primary insomnia: only 20% of cases, mostly due to stress

Different parasomnias

Sleep terrors/night terrors: occur in the sleep cycle nREM sleep walking- stages 3 & 4 of NREM, occur early in night, most common in childhood bruxism- clenching or grinding of teeth during sleep, can lead to headaches, ear aches, tooth damage

NREM Stages of Sleep

Stage 1: drifting off. Brain activity begins to slow. Your muscles may twitch, and you are easily awakened. Light stage of sleep- typically lasts a few minutes. Stage 2: You're truly but lightly asleep. Body temperature cools. Breathing rate and pulse slow. You are easily aroused. Lasts about 15 mins, but over the course of the night you spend more time in this stage than any other. EEG waves become slower and broader. Stage 3 & 4: tall, slow brainwaves. Stage 3- waves are just beginning to appear, as you are falling into a deep sleep. By stage 4, more than half of the brain waves are the tall, slow waves characteristic of deep sleep. Breathing rate and pulse slow even more, blood pressure drops. You are now deeply sleeping and are difficult to arouse. Talking and sleepwalking would occur in this stage. During stage 4, the pituitary gland releases growth hormone, important for the repair of wear and tear on body tissue. Spend 30 min or more in stage 4, early on in the night, but you spend less and less later.

REM Stage

Stage 5: prompted by signals from the pons in the brain stem. The pons inhibits the release of neurotransmitters necessary for muscle movement- meaning you can't act out your dreams. When it fails, you can experience rare and potentially dangerous sleep disorder called REM behavior disorder. Three muscle groups remain active- respiratory muscles, inner ear muscle, and eye muscles to produce rapid eye movement. Brain wave activity is similar to when someone's awake. The brains oxygen consumption is higher than it is even when you're performing complex tasks.

Parasomnias

a condition in which unusual events accompany sleep

circadian rhythm

a pattern of physical and behavioral changes that follows a 24-hour cycle, in accordance with the hours of darkness and light.

Sleep

a reversible behavioral state of perceptual disengagement from and unreposveneps to the environment.

What makes you sleep

o Circadian Rhythm - your biological clock o Melatonin - pineal gland starts producing melatonin at 8pm, hits peak at midnight, and declines to daytime amounts at 7am.

Physical impact on health from short amounts of sleep

o Common Cold - less sleep, more susceptible to the common cold o Type 2 Diabetes, heart disease, obesity, depression

Two types of sleep

o Non-REM: stages 1-4, half asleep, HR slows, transition to deep sleep, and deep restful sleep o REM: stage 5, rapid eye movement, brain activity - dreaming!

Treatment to sleep disorders

o Sleep behavior classes o Treat underlying health problem o Medications - highly addictive, significant side effects o Complementary and Alternative Medicine Melatonin supplements Chamomile Yoga and Tai Chi o Cognitive Behavioral Therapy Change automatic thought patterns Worry control

How to get a good nights sleep

o Stick to a schedule o Do not exercise immediately before bed o Avoid caffeine in afternoon o Avoid alcohol and large meals right before bed o Relax o Have a good sleeping environment o Don't lie in bed awake (Dr. Crista's 200 Rule)