The Sleep Cycle

cp and honors psych

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Objectives:

• Define sleep
• Identify the main theories of sleep
• Differentiate between the stages of sleep
• Understand sleep cycle

What Is Sleep?

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• An altered state in which people become relatively unaware of external stimulation

Studying Sleep

• (1953) EEG records brain wave activity
• Frequency and strength

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• EOG record eye movements
• EMG record muscle movements
• EKG records activity of the heart

EEG and Sleep Stages

• Awake = Beta Waves
• Stage 1 = Theta Waves
• Hypnagogic State
• Stage 2 = Theta Waves
• Sleep Spindles
• Stage 3 = Delta Waves
• Stage 4 no longer exists
• Bedwetting, Sleep talk/walk
• Night Terrors are all Stage 3
• REM = Mimic’s Beta Waves
• Atonia, DREAMING!

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Why Do We Sleep At Night?

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• Circadian Rhythm
• Internally generated sleep/wake cycle connected to 24-hour pd of earth’s rotation

Sleep Cycle

• Roughly 4 periods of REM sleep per night
• Sleep becomes lighter as night wears on
• REM sleep becomes longer towards am

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If you went to bed around 10pm…

Animal sleep… Your theory?

Why Do We Sleep?

• Evolutionary Theory: Protective function, keeps people tucking away at night, safe from predators.

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• Recuperative Theory: Conserves energy, restores body tissues depleted during daily activity
• REM: hormones released that influence thinking & memory formation, mental organization; counteract fatigue, irritability, inattention
• NREM: body replenishes itself (tissue restoration and release of growth hormone)

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How Much Sleep Do I Need?

• Infants
• 20 hours
• 50% REM
• Children/Adolescents
• 10 hours
• 25-30% REM
• Bed Later, Up Later
• Adults
• 8 hours
• 20% or less REM
• Elderly
• 6 hours
• Bed Later, Up Earlier

What If I Miss Sleep?

• Effects On Body
• Immune system weakens
• Metabolic malfunction
• Varied body temp

• Effects On Brain
• Moodiness
• Decreased cognitive performance
• Learn slower, remember less, loss concentration & creativity
• Blurred vision
• Disorganized speech
• Hallucinations

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Sleep deprivation

Sleep Activities

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• Am I Sleep Deprived?

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• Sleep Myths Quiz

Am I Sleep Deprived? Yes/No

• I need an alarm clock to wake up for school.
• It’s a struggle to get out of bed in the morning.
• I hit the snooze bar several times to get more sleep.
• I feel tired, irritable and stressed out during the week.
• I have trouble concentrating and remembering.
• I feel slow with critical thinking, problem solving and being creative.

• I often fall asleep in boring classes or warm rooms.
• I often fall asleep within 5 minutes of getting into bed.
• I often feel drowsy while driving.
• I often sleep extra hours on weekend mornings.
• I often need a nap when I get home from school.
• I have pink circles around or dark circles under my eyes.

Am I Sleep Deprived? Yes/No

• An answer of “yes” to three or more of the previous questions indicates sleep deprivation.

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• You can easily improve your mood, performance and health by getting more sleep!

Discussion

• How has sleep deprivation affected your life? Which activities contribute most to your sleep deprivation?

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Your SCN is impacted by you staring at light. After you turn off your screens, the SCN sends messages to your pituitary gland to send messages to your pineal gland to make Melatonin, It takes a while for the messages to send and for Melatonin to flood your body making you tired, Melatonin ensures that you are tired for 8-10 hours, so if you turn off your phone at 1 am. You will feel awake around 11am.

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Sleep hygiene

Block out any light where you sleep. Cover up blinking lights on stereos or power strips, make it dark and cave-like in your room. Total darkness is key

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Use a desk lamp for reading paper/books before falling asleep, not the overhead light as full light delays production of melatonin. When your eyes are staring at light sources, it takes several hours after you turn it off for melatonin to start being produced. Turn off screens (phone, TV, iPad, laptop) at least 2 hours before bed.

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Keep your bedroom at a comfortable temperature (ideally, slightly cooler than daytime sitting around inside temp), if you can

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Spend some time each day to be outside in daylight. Time spent outside during the day helps to preserve your body’s sleep and wake cycles, circadian rhythm.

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Be physically active most days. Exercise promotes regular sleep/wake patterns as well as reduce stress. Avoid exercise and other vigorous activities three-to-four hours before going to bed to avoid awakening the body even more.

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7. Eat a regular meal schedule. By eating smaller meals near bedtime, you will be more likely to have a good night’s sleep. Don’t eat a big meal before sleep.

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8. Go to bed only when you are sleepy. If you can’t fall asleep after 20 minutes, get out of bed and do a relaxing activity somewhere else until you feel sleepy again. Don't look at screens; books or magazines are great.

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9. Try deep breathing or relaxation techniques if you’re having trouble falling asleep due to stress or anxiety.

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10. Minimize Sleep Disruptions. Go to bed around the same time every night, your brain likes routine.

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Sleep hygiene

Eat a regular meal schedule. By eating smaller meals before bedtime, you will be more likely to have a good night’s sleep. Don’t eat a big meal before sleep.

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Go to bed only when you are sleepy. If you can’t fall asleep after 20 minutes, get out of bed and do a relaxing activity somewhere else until you feel sleepy again. Don't look at screens; books or magazines are great.

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Try deep breathing or relaxation techniques if you’re having trouble falling asleep due to stress or anxiety. Practice thinking about the good stuff from your day before sleep –rather than the worst stuff.

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Minimize Sleep Disruptions. Go to bed around the same time every night, your brain likes routine.

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INSOMNIA

• Difficulty in initiating sleep or in staying asleep or waking up earlier

• Nonrefreshing, nonrestorative sleep

• Fatigue, concentration or memory impairment

• Mood disturbances, motivation, initiative reduction

• Daytime sleepiness • Tension headache

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Insomnias

• Prevalence: 33%

• Accompanied with daytime consequences: 10%

• Last less than 1 month: 4% (transient insomnia)

• Last more than 1 year: 85% (persistent insomnia)

• Male:female = 1:1.4

• Increase with age: above 65 years: 50%

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