Bell Work What effect does sleep have on behavior?

Rhythms

Biological Rhythms Annual cycles: seasonal variations Seasonal depression 28 Day Cycle: menstruation 24 hour cycle: circadian rhythm 90 minute cycle: sleep cycle

Circadian Rhythms Internal 24 hour clock Body changes throughout the day Hormones, temperature, etc. Think jet lag…

Sleep

The Sleep Cycle REM (Rapid Eye Movement) NREM (Non-REM) – 4 stages Takes about 90 min to get through all cycles of sleep… Brain waves change between stages

Stages of NREM

Stage 1 Transition between wake and sleep. Lasts between 1 and 5 minutes and occupies approximately 2-5 % of a normal night of sleep. consists mostly of theta waves brief periods of alpha waves

Stage 2 Muscle activity and awareness decrease Body temperature cools May perceive falling Theta waves w/o alpha Most time is spent here (45-60%)

Stage 3 First stage of deep sleep Less aware of stimuli Time in stage 3 decreases throughout the night Delta waves Temperature, breathing, heart rate at lowest Most common NREM stage for dreams…

Stage 4 More frequent delta waves than stage 3 Deepest sleep…

Go back to 3, then 2, then 1.

REM Sleep

REM This is a very active stage of sleep. Composes 20-25 % of a normal nights sleep. Breathing, heart rate and brain wave activity quicken. Similar to being awake Vivid Dreams can occur. Most dreams occur here From REM, you go back to Stage 2 Body is essentially paralyzed during REM.

Sleep Disorders

Insomnia Persistent problems falling asleep Effects 10% of the population Primary versus Secondary Insomnia Primary – cannot be attributed to a medical cause Secondary – symptom of medical disorder

Narcolepsy Suffer from sleeplessness and may fall asleep at unpredictable or inappropriate times. Directly into REM sleep Less than .001 % of population.

Sleep Apnea A person stops breathing during their sleep. Wake up momentarily, gasps for air, then falls back asleep. Very common, especially in heavy males. Can be fatal.

Night Terrors Wake up screaming and have no idea why. Not a nightmare. Most common in children (boys) between ages 2-8.

Sleep Walking Most often occurs during the first few hours of sleeping and in stage 4 (deep sleep). May look/act like they’re awake If you have had night terrors, you are more likely to sleep walk when older.

Wrap Up What stage of sleep