SLEEP INTRODUCTION TO PSYCHOLOGY HOW WE LOVE SLEEP

SLEEP INTRODUCTION TO PSYCHOLOGY

HOW WE LOVE SLEEP!

BIOLOGICAL RHYTHMS AND SLEEP

CIRCADIAN RHYTHM - THE BIOLOGICAL CLOCK; REGULAR BODILY RHYTHMS (IE: TEMPERATURE AND WAKEFULNESS) THAT OCCUR ON A 24 HOUR CYCLE • Examples: • Body temperature rises as morning approaches, peaks during the day, dips for a time in early afternoon (when many people take siestas), and then begins to drop again before we go to sleep • Thinking is sharpest and memory most accurate when we are at our daily peak in circadian arousal • Pulling an all-nighter we may feel groggiest at 4: 00 am, and then we get a second wind after our normal wakeup time arrives

CIRCADIAN RHYTHM – HOW IT WORKS • Bright light in the morning tweaks the circadian clock by activating light-sensitive retinal proteins – these proteins trigger signals to the brain to decrease its production of melatonin in the morning and increase it in the evening • Bright light at night will delay sleep and reset out biological clock when we stay up late and sleep in on weekends • Sleeping until noon and then going to sleep 11 hours later does not make for healthy sleep • Due to younger people staying up late and then trying to get 8 hours of sleep, they end up with a 25 hour day • The problem is artificial light (ie: lights, screens, phones)

SLEEP STAGES ABOUT EVERY 90 MINUTES, WE PASS THROUGH A CYCLE OF 5 DISTINCT SLEEP STAGES Stage 1 – Sleep • Slipping from relaxed state to sleep. Breathing becomes slowed and the brain waves are irregular • During this brief stage one may experience fantastic images resembling hallucinations (sensory experiences that occurs without a sensory stimulus. ) • You may have a sensation of falling or floating

SLEEP STAGES Stage 2 – Relaxed more deeply (lasts about 20 minutes) • This stage is characterized by the periodic appearance of sleep spindles – bursts of rapid, rhythmic brain wave activity • Although you can still be awaked without much difficulty at this stage, you are still very much asleep

SLEEP STAGES Stage 3 and 4 • Stage 3 is a transitional stage that moves you into the deep sleep of stage 4 • First in stage 3 and increasingly in stage 4, your brain emits large, slow delta waves which last for about 30 minutes – it would be very difficult to wake you up at this point • It is usually at the end of stage 4 that children wet the bed or begin sleepwalking

SLEEP STAGES REM Sleep – Rapid Eye Movement Sleep • A recurring sleep stage during which vivid dreams commonly occur (paradoxical sleep) – the muscles are relaxed, except for minor twitches, but other body systems are active. • Brain waves become more rapid again • Your heart rate rises • Breathing becomes more rapid and irregular • Every half minute or so your eyes dart around in momentary bursts of activity behind closed eye lids

SLEEP STAGES REM Sleep (Continued) • Your muscles are completely relaxed because your brainstem is blocking messages • There may be an occasional finger, toe, or facial twitch, however you are essentially paralyzed • You also can not be easily awakened Your brain’s motor cortex is active, but your brainstem blocks its messages • The Rapid Eye Movements typically announce the beginning of a dream

FULL SLEEP CYCLE • The sleep cycle repeats itself about every 90 minutes • As the night wears on, deep stage 4 sleep gets progressively briefer and then disappears • REM and Stage 2 sleep periods get longer • By morning 20 -25% of our average night’s sleep – about 100 minutes – has been REM sleep • 37% of people report rarely or never having dreams that they remember the next morning • Unbeknownst to these people, they spend about 600 hours a year experiencing some 1500 dreams, or more than 100, 000 dreams over a typical lifetime – dreams that are never acted out are because of REMs protective paralysis

WHY DO WE SLEEP? • Allowed to sleep unhindered, most adults will sleep at least 9 hours a night • With that much sleep, we awake refreshed, sustain better moods, and perform more efficient and accurate work • If we compare a 9 hour night of sleep with that of 5 hour nights that many of us get, we begin to accumulate a sleep debt that our bodies cannot pay off by one long marathon sleep • The brain keeps an accurate count of sleep debt for at least 2 weeks • When our bodies yearn for sleep, we begin to feel terrible – when trying to stay awake, we will eventually lose – sleep always wins • WE SLEEP BECAUSE WE NEED SLEEP

SLEEP LOSS • Many of us are suffering from patterns that not only leave us sleepy, but also prevent us from having an energized feeling of well being • Teens typically need 8 -9 hours of sleep – however are now getting on average nearly 2 hours less than their counterparts 80 years ago • Even when awake, students often function below their peak due to lack of sleep • 4 in 5 American teens wish they could get more sleep • In a study in 1997, 80% of Stanford students were dangerously sleep deprived

THE EFFECTS OF SLEEP LOSS SLEEP DEPRIVATION DOES THE FOLLOWING: • Irritability • Low functioning • Hunger arousing hormone increases, while hunger suppression hormone decreases • Stress hormone, Cortisol, is increases which stimulates the body to make fat • Immune cells which help fight off infection and cancer can be suppressed (which is way doctors say to sleep more when infection sets in so that immune cells can be boosted) • Chronic sleep debt alters metabolic and hormonal functioning (can lead to aging, hypertension, and memory impairment) • Slow response time

WHAT DOES SLEEP DO FOR US? 1. Sleep protects • A species sleep pattern tends to support its ecological needs 2. Sleep helps us recuperate • Helps us restore and repair brain tissue and other cells 3. Sleep is for making memories • Storing and building 4. Sleep feeds creative thinking • dreams 5. Sleep plays a role in the growth process • Releases growth hormones

SLEEP DISORDERS Regardless of the need for sleep, some people end up with diagnosed sleep disorders • INSOMNIA • 1 in 10 adults and 1 in 4 older adults, complain of INSOMNIA –persistent problems in falling asleep and staying asleep • NARCOLEPSY • • A sleep disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM, often at inappropriate times: • After a terrific swing at a baseball game • Laughing loudly or shouting angrily Typically, whatever happened 5 minutes before the narcoleptic attack, is forgotten by the individual

SLEEP DISORDERS • Sleep Apnea • A sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings • 1 in 20 people have this disorder • It repeats hundreds of times each night depriving them of natural sleep rhythms • Loud snoring comes with this • Night Terrors • • Target mostly children • They may sit up or walk around, talk incoherently, experience a doubling of heat and breathing rates, and appear terrified • They seldom wake up during this and often don’t remember They ARE NOT nightmares