Sleeping

Sleep ▣ Sleep is a state of consciousness. ▣ We are less aware of our surroundings. Circadian Rhythm ▣ Circadian Rhythm- our body’s synchronizing to 24 hour biological clock ▣ Our body cools at night, heats up in the morning, and dip slightly in the afternoon (nap time!) ▣ Amount of sleep we need is biological (adenosine) ▣ What one invention has had the biggest impact on sleep? ▣ The 25 hour clock ▣ On average most adults would sleep about 9 hours if uninterrupted Circadian Rhythm ▣ Light activates light sensitive retinal proteins ▣ These proteins signal to the brains suprachiasmatic nucleus (SCN). ▣ It’s in the hypothalamus and it causes the pineal gland to decrease the production of melatonin in the morning and increase it in the evening ▣ The pineal gland releases melatonin in response to darkness ▣ Most teens and adults are energized at night and older adults are energized in the morning. Sleep ▣ Two main types ◼ Non-Rapid Eye Movement Sleep (NREM) ◼ Rapid Eye Movement Sleep ▣ 4 stages of sleep ▣ Used to be 5 but now 3 and 4 have been combined Sleep Cycle • Use an EEG machine to measure stages of sleep. • When you are the onset of sleep you experience alpha waves. • Produces mild hallucinations, like a feeling of falling (day dreaming) NREM 1 ▣ Kind of awake and kind of asleep. ▣ Only lasts a few minutes, and you usually only experience it once a night. ▣ Your brain produces Theta Waves. ▣ Produces mild hallucinations, like a feeling of falling (day dreaming) Click the couple to see Theta Waves NREM 2 Click image to see Stage Two of sleep. ▣ More Theta Waves that get progressively slower. ▣ Begin to show sleep spindles… short bursts of rapid brain waves. ▣ Could still be awoken easily but clearly asleep ▣ 20 minutes NREM 3 ▣ ▣ ▣ ▣ Slow wave sleep. You produce Delta waves. If awoken you will be very groggy. Vital for restoring body’s growth hormones and good overall health. ▣ Hard to be woken from ▣ Lasts for about 30 minutes Click boys to see deep From stage 3, your brain begins to sleep. speed up and you go to stage 2….then The ascension ▣ After stage 3 you begin to ascend through the sleep cycles returning to stage 2 where you spend half of your night ▣ Then for about 10 minutes you enter REM sleep REM Sleep ▣ Rapid Eye Movement ▣ Heart rate speeds up. breathing becomes rapid and irregular ▣ Often called paradoxical sleep (awake on the inside paralyzed on the outside). ▣ Brain is very active. ▣ Dreams usually occur in REM. ▣ Body is essentially paralyzed. ▣ REM Rebound ▣ Genitals get aroused except for scary dreams Click boy dreaming to see REM sleep. ▣ The sleep cycle repeats itself every 90 minutes ▣ NREM 3 grows shorter and disappears ▣ REM and NREM-2 periods grow longer ▣ 20-25% percent in REM sleep ▣ 600 hours a year experiencing 1500 dreams Sleep Paralysis ▣ Person experiences an inability to move, speak, or react ▣ Often accompanied by terrible hallucinations ▣ It may happen due to interrupted REM sleep, where the body is immobilized Sleep Theories ▣ Protection (evolution) ▣ Recuperate (brain neurons repair) ▣ Rebuild memories ▣ Creative thinking ▣ Growth (pituitary gland releases growth hormone) Benefits ▣ Happier ▣ Less depressed ▣ Healthier weight ▣ More productive ▣ Less likely to get sick ▣ Less likely to make errors ▣ Better Memory Insomnia ▣ Persistent problems falling asleep ▣ Effects 10% of the population ▣ People underestimate how much sleep they are getting ▣ Aids such as sleeping pills or alcohol may worsen problem by reducing REM sleep Narcolepsy Click above to see Skeeter the narcoleptic dog. ▣ 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. Somnambulism • Sleep Walking • Most often occurs during the first few hours of sleeping and in stage 3 (deep sleep). • If you have had night terrors, you are more likely to sleep walk when older. REM sleep behavior disorder ▣ Normal REM paralysis does not occur. ▣ Leads to talking, twitching, kicking, punching, acting out dreams Dreams Dreams: a sequence of images, emotions, and thoughts passing through a sleeping person’s mind. Dreams are notable for their hallucinatory imagery, discontinuities, and incongruities, and for the dreamer’s delusional acceptance of the content and later difficulties remembering it. • 6 years of our life Dream Theories • Freud’s fulfillment • Information-processing/Consolidation • • • Physiological function Activation Synthesis Cognitive development 59 Freud’s Theory of Dreams ▣ Dreams are a roadway into our unconscious. They allow us to fill our ID desires ▣ Manifest Content (storyline) ▣ Latent Content (underlying meaning) Consolidation Theory ▣ Dreams are a way to help sift, sort, and fix the day’s experiences in out memory. ▣ We tend to dream more when we are more stressed. ▣ During sleep, memory networks are reactivated without new sensory input, which helps stabilize and reorganize memories into long-term storage Activation-Synthesis Theory ▣ Our Cerebral Cortex is trying to interpret random electrical activity we have while sleeping. ▣ That is why dreams sometimes make no sense. ▣ Biological Theory. Physiological function ▣ Helps our brain develop and preserve neural pathways Cognitive development ▣ Dreams represent cognitive development ◼ The more developed your brain the more complex your dreams