CHP.2 SLEEP

States of Consciousness

• Consciousness: awareness of ourselves and our environment.

• It has a single focus: we attend to one thing at a time.

• New things and novel ideas capture attention because our sensory systems identify change.

• Example: after noticing a new building on the way to school, we may suddenly notice it every day; similarly, buying a Jeep Wrangler can make Jeep Wranglers appear everywhere.

• This illustrates how our conscious awareness is shifted by experiences and goals (selective attention).

Hypnosis

• Hypnosis is an induced altered state of consciousness that heightens openness to suggestion without losing a sense of self or control.

• Under hypnosis, people do only what they would be willing to do in their usual fully conscious state, nothing more.

• Not everyone is easily hypnotized.

• Great candidates: open-minded, very creative, deeply absorbed in imaginative activities.

• During hypnosis, the subject is NOT asleep.

• They adhere to their usual moral standards.

• They are capable of saying no or stopping.

Uses of Hypnosis

• Shown to be effective in treating pain and anxiety.

• Some have used hypnosis successfully for anxiety, depression, gastrointestinal disorders, skin conditions, and other troublesome conditions.

• In therapeutic hypnosis, a state of suggestibility makes someone more able to respond positively to recommendations (e.g., reducing smoking, feeling less pain during dental work).

• Research shows hypnosis is ineffective in memory recovery; most recovered memories may be false memories created under suggestion of an overeager hypnotherapist.

• Age regression therapy is not considered viable.

Sleep

• Even when asleep, the brain remains active; perception is reduced but not completely shut.

• Circadian Rhythm: a 24-hour biological clock reset by sunlight.

• Body temperature rises as morning approaches, peaks during the day, dips in early afternoon, and drops before sleep.

• Thinking is sharpest and memory most accurate near the daily peak in circadian arousal.

• Teenagers tend to have a late circadian clock and sleep late; around age ~20 the cycle tends toward an adult pattern.

• Jet lag and shift work disrupt circadian rhythm.

Circadian Rhythms

• The 24-hour cycle biological clock is reset by sunlight.

• Body temperature pattern: rises in the morning, peaks during the day, dips in the early afternoon, then drops before sleep.

• Peak circadian arousal corresponds to sharper thinking and better memory.

• Teenage circadian patterns skew late; maturation around age 20 shifts toward adult rhythm.

• Disruptions include jet lag and shift-work.

Jet Lag & Melatonin Therapy

• Jet lag is a disruption of circadian rhythms from travel across time zones.

• Travel impact differs by direction: it can be easier to adjust when flying to certain destinations (e.g., westward) and harder in others (e.g., eastward).

• General rule: it generally takes about one day to reset your circadian clock for each hour of time change.

• Melatonin is commonly used to help treat jet lag in some cases.

• Example dosage snapshot: 3 mg melatonin is used in some jet lag protocols.

Melatonin

• Melatonin is the “sleep hormone” secreted into the bloodstream.

• Darkness increases melatonin production, signaling the body to prepare for sleep.

• Light hitting the retina signals the suprachiasmatic nucleus to decrease melatonin output.

• Younger people tend to produce melatonin later and can stay up later; this helps explain later bedtimes for youth.

Sleep Cycle basics

• Approximately every 90 minutes we pass through four distinct sleep stages.

• An EEG measures stages of sleep; brain wave patterns include:

  • Beta waves: awake

  • Alpha waves: drowsy

  • Theta waves: light sleep

  • Delta waves: deep sleep

• Sleep cycles include NREM (non-REM) stages and REM sleep in alternating pattern across the night.

Sleep Stages (Non-REM and REM)

• Stage 1 (N1): lightest sleep; Theta waves prominent; transitional between wakefulness and sleep; lasts ~1-5 minutes; brief hypnagogic sensations (e.g., feeling of falling).

• Stage 2 (N2): about 20 minutes; Theta waves continue; sleep spindles (short bursts of rapid brain waves) appear; body temperature drops; heart rate slows; breathing becomes shallow.

• Stage 3 (N3): Delta waves appear; deepest sleep; night progresses, Stage 3 shortens and may disappear; important for rest and growth hormone release; if awoken, grogginess and disorientation can occur.

• REM sleep: Rapid Eye Movement; brain is active, but the body is paralyzed (muscle atonia); dreams usually occur in REM; heart rate and breathing increase; REM accounts for about 20 ext{%} of sleep time; typical night involves about 5 REM periods of 15-45 minutes each.

• The cortex is interpreting random neural activity during REM (activation-synthesis) while the limbic system (emotions) is active; the frontal lobe is relatively quiet, contributing to dream bizarre logic.

Non-REM sleep: organizational overview

• Non-REM sleep accounts for approximately 80 ext{%} of sleep time and is divided into Stages 1–3/4 (as described above).

REM Rebound & Sleep Function

• REM Rebound: REM sleep increases after REM sleep deprivation.

• If you miss REM sleep for a period and then sleep more, you’ll dream more as the body compensates.

• Why do we sleep?

  • Sleep restoration: repair, rewire, and reorganize brain and body; helps immune function; clears toxic waste and amyloid-related proteins linked to Alzheimer’s disease.

  • Sleep facilitates memory consolidation: replays experiences stored in the hippocampus and moves them to permanent storage in the cortex; memory recall improves after a night of sleep.

  • Phrase “sleep on it” reflects consolidation benefits.

Sleep Deprivation & Health Consequences

• Sleep debt cannot be paid off in one marathon sleep; brain tracks sleep debt for at least two weeks.

• About 75 ext{%} of high school students report getting less than 8 hours of sleep per night.

• Consequences include impaired concentration, mood changes, and increased risk of depressive disorders; teens sleeping 5 hours or less have a 70-80 ext{%} higher risk of depression and suicidal thinking.

• Sleep deprivation can lead to weight gain (ghrelin increases appetite), immune suppression, higher risk of illness; high blood pressure risk doubles or multiplies when sleeping <6 hours; memory impairment; moodiness; occasional hallucinations.

• Teens typically need about 9 hours of sleep per night, but average about 2 hours less.

• Microsleep: brief episodes of sleep lasting only seconds.

Sleep and Accidents (Graph Reference)

• A chart shows a relationship between sleep duration and accident frequency: less sleep correlates with more accidents; more sleep correlates with fewer accidents.

• Illustrative data points (from the chart): approximate values range across the low sleep vs high sleep conditions around daylight-saving changes and typical Mondays.

• Noting seasons: spring time change (hour sleep lost) vs fall time change (hour sleep gained) effects on accidents around those transitions.

Sleep Disorders

• There are over 100 different types of sleep disorders.

• Roughly 50 to 70 million people suffer from sleep disorders.

• Two major categories:

  • Dysomnias: problems initiating, maintaining, or otherwise excessive sleepiness.

  • Parasomnias: disruptive physical behaviors that occur during sleep.

Insomnia

• Persistent problems falling/staying asleep; most common sleep complaint in the U.S.

• Affects about 1/5 of adults.

• Causes include stress, worry, circadian rhythm changes, medical problems, or substance abuse.

• Best approaches are natural strategies (e.g., lights off, cooler room, avoid clock watching); sleeping pills and alcohol often worsen sleep by reducing REM sleep and can lead to tolerance.

Narcolepsy

• Marked by excessive sleepiness and sudden sleep episodes, even during conversation or activities.

• Episodes usually last less than 5 minutes; can involve cataplexy (loss of muscle tone).

• Narcolepsy affects < 1 ext{%} of the population.

• Some research notes that hypocretin (orexin) deficiency is linked; dogs with missing hypocretin show narcolepsy symptoms; replacement in model showed improvement; potential hypocretin-based treatment forecasted in about 5 years.

Sleep Apnea

• A person stops breathing during sleep for at least 10 seconds or longer; affects about 1/20 people.

• Symptoms include brief awakenings with gasping or snorting; repeats hundreds of times per night.

• Sleep apnea deprives delta-wave sleep and can be fatal if untreated.

• Treatments range from physical aids (e.g., CPAP device with a mask) to surgical options such as tonsil removal or jaw repositioning. A simple home remedy includes sewing tennis balls to the back of a pajama top to prevent back-sleeping.

REM Sleep Behavior Disorder (RBD)

• Normal REM sleep paralysis is absent; individuals may twitch, talk, kick, or punch while dreaming.

• Affects about 1/100 people.

Somnambulism (Sleep Walking)

• Occurs in about 1/15 people; most often in the first few hours of sleep and during Stage 3 (deep sleep).

• Usually unrecalled; may be genetically linked; often occurs when stressed or sleep-deprived.

• Most episodes end with returning to bed on one’s own or with guidance.

• Sleepwalking behaviors can range from mild to complex actions, including moving furniture, using the bathroom, or even driving.

Dreams

• Dreams are usually vivid, emotional, and bizarre.

• For both sexes, about 8/10 dreams contain negative events or emotions.

• Dreams often incorporate traces of the day’s experiences.

Dream Facts

• About 12 ext{%} of people dream in black and white.

• Dream intensity and pleasantness relate to stress and life satisfaction.

• Women tend to have more nightmares than men.

• Eating before bed increases nightmare likelihood by signaling higher brain activity.

• Sleep talking often involves swearing.

• Across a lifetime, a person may spend about 6 years dreaming.

• Blind people do dream.

• Early recall: five minutes after a dream, about half the content is forgotten; after ten minutes, about 90% is forgotten.

• Dreams typically feature faces you’ve seen in real life or on TV.

• Women tend to dream about indoor settings; men about outdoor scenes.

• Most dreams involve more than one person; on average, about 3 people are present.

• In many dreams, men are more likely to be aggressors; women more likely to be victims.

• The most common emotion in dreams is anxiety.

Common Dream Themes

• Be chases or attacked

• Falling or drowning

• Being lost or trapped

• Being naked in public

• Being injured, ill, or dying

• Being in a natural disaster

• Having trouble taking a test

• Having trouble with a car/transport

• Missing your ride

• Having property damaged or lost

• Trouble operating a telephone or machine

• being menaced by a spirit

Functions of Dreams

• Activation-Synthesis Theory: the cerebral cortex interprets random neural activity during sleep; visual-processing areas may be activated, leading to nonsensical dream content.

• Limbic System (emotional center) is active; amygdala (fear and aggression) is active; frontal lobe (logic and judgment) tends to be idle during dreaming.

Information Processing / Consolidation Theory

• Dreaming may reflect the brain’s process of sorting, consolidating, and storing day’s experiences.

• REM sleep appears linked to memory consolidation; deprivation of REM sleep impairs performance on tasks learned that day.

• Brain scans support REM sleep-memory link.

• Educational data: high-achieving students tend to sleep about 25 minutes longer per night than lower-achieving peers.

• Sacrificing sleep to study often worsens next-day performance due to diminished processing and learning.

Psychoactive Drugs: Overview

• Psychoactive drugs alter brain function and affect mood, perception, or consciousness.

• Tolerance: diminishing effect with regular use of the same dose requiring larger doses for the same effect.

• Addiction: compulsive substance use despite harmful consequences.

• Withdrawal: discomfort or distress after stopping an addictive drug or behavior.

• Three main categories: ext{Depressants}, ext{Stimulants}, ext{Hallucinogens}.

Depressants

• Drugs that calm neural activity and slow body functions.

• Examples: Alcohol, Opioids.

• Effects:

  • Slows neural activity that controls judgment and inhibitions.

  • Associated with millions of deaths worldwide due to accidents and injuries.

  • Increases aggressive behavior tendencies in some contexts; surveys show significant percentages of offenders and victims had been drinking in incidents.

  • Slows neural processing, leading to slower reactions, slurred speech, and balance problems.

  • Disrupts memory; can cause blackouts and impaired recall of events.

  • Reduces self-awareness.

• Alcohol: acts as a depressant; initially relaxes, then slows brain areas responsible for self-control; reduces inhibition and can impair judgment; long-term use depresses natural endorphin production; alcohol-related behavior can involve increased risk of harm.

• Opioids: depress neural activity to reduce pain and anxiety; act as agonists for endorphins; repeated exposure can reduce endogenous endorphin production; heroin is a well-known opioid; overdose risk is high; overdose can lead to slowed breathing and death.

Stimulants

• Drugs that excite neural activity and speed up bodily functions; pupils dilate; heart rate and breathing increase; blood sugar rises; energy and confidence increase.

• Major examples: Caffeine, Cocaine.

• Caffeine:

  • World’s most widely consumed psychoactive substance.

  • A mild dose lasts 3-4 hours.

  • Can impair sleep, raise blood pressure, reduce fertility, contribute to bone loss and ulcers, and cause heartburn.

  • Like other drugs, tolerance and withdrawal can occur (e.g., fatigue and headaches).

• Cocaine:

  • Powerful, addictive stimulant.

  • Historically used in early Coca-Cola formulations; today used in powder form or crack cocaine.

  • Rapid entry into the bloodstream produces a rush of euphoria but depletes brain dopamine, serotonin, and norepinephrine.

  • Within about an hour, a crash of depressive symptoms follows as drug effects wear off.

  • Cocaine use may lead to emotional disturbances, suspiciousness, convulsions, cardiac arrest, or respiratory failure.

Hallucinogens

• Distort perceptions and evoke sensory images in the absence of sensory input (psychedelics).

• Example: Marijuana.

Marijuana (Cannabis)

• Can be smoked or ingested; contains THC and produces a mix of effects.

• In a single joint, THC may induce psychiatric symptoms such as hallucinations, delusions, and anxiety.

• Amplifies sensory sensitivity (colors, sounds, tastes, smells).

• Produces relaxation and disinhibition similar to alcohol, with a potential euphoric high.

• THC can linger in the body for more than a week and can impair motor coordination, perceptual skills, reaction time, and memory formation.

• Risks include increased likelihood of traffic accidents, chronic bronchitis, psychosis, social anxiety, depression, and suicidal thoughts; may contribute to impaired attention, learning, and memory and possible academic underachievement.