750 likes | 757 Views
This article delves into the levels of consciousness and explores the various states of awareness. It also examines the importance of sleep and the different stages of the sleep cycle.
E N D
Consciousness • Awareness of yourself and the environment. • The immediate awareness of mental activities and internal sensations, and of the external environment
How do we adjust from a state of conscious awareness into various states of unawareness and unconsciousness? • Some things occur naturally in the world that make us either more or less aware • Some things we do purposefully that makes us either more or less aware
Biological Rhythms - natural life cycles that help to guide our levels of awareness and our behaviors
Examples of Biological Rhythms • Annual Cycles – Seasonal changes affecting moods, appetite, sleep patters • Twenty-Eight Day Cycle – Female Menstrual Cycle • Twenty-Four Hour Cycle – Daily cycle of levels of alertness, hormones, body temperature, etc. • Ninety-Minute Cycle – Sleep Cycle
Examples of Things We Do • Diet • Psychoactive Drugs • Exercise and Health • Stress • Lifestyles • Travel • Work Schedules
Why Do We Sleep? Strengthening Memory • The Science of Sleep Part I • The Science of Sleep Part II
Why do we sleep? • Adaptive Theory of Sleep (Evolutionary Perspective) • Unique sleep patterns of different animals evolved over time to promote survival and environmental adaptation. • When and where we sleep, and for how long, is determined by your status in the hierarchy • Lions sleep anytime, anywhere. Mice, short bursts of sleep in well protected nests.
Why do we sleep? • Restorative Theory of Sleep (Biological Perspective) • Sleep promotes physiological processes that restore and rejuvenate the body and the mind • It works on a biological clock schedule to ensure that we have the opportunity to sleep • NREM (typically dreamless) = bodily restoration and REM (dream) = mind restoration
Circadian Rhythms • A cycle or rhythm that is roughly 24 hours long. • Our biological clock is synchronized with the 24-hour cycle of day and night, producing a general pattern of wakefulness and sleep. • Circadian rhythms are hardwired and a natural part of the body’s daily routine.
Circadian Rhythms • The circadian rhythms related to wakefulness and sleep are controlled by the suprachiasmatic nucleus (SCN), which is a cluster of neurons in the hypothalamus
The Sleep-Wake Cycle • The SCN is connected to the visual system of the body. • When there are decreased levels of light, the SCN triggers the pineal gland to release melatonin, which causes sleepiness and reduced activity level • When there are increased levels of light, melatonin levels decrease and conscious awareness level increase
Free-Running Circadian Rhythms • Experiments in which all environmental time cues are removed – no clocks, and light is artificially controlled • The body creates its own sleep-wake cycle that is roughly one-hour off of normal sleep and wake times – it works on a 25 hour day schedule
Sleep • There are two different types of sleep: • NREM Sleep: quiet, typically dreamless sleep in which rapid eye movements are absent • REM Sleep: type of sleep during which rapid eye movements and dreaming occur and voluntary muscle activity is suppressed
Stages of SleepThe Stages of Sleep • When you are awake and alert, brain waves known as Beta Waves are generated in the brain • After your head hits the pillow, you close your eyes, and your muscles begin to relax, the brain begins to generate Alpha Waves as you prepare for sleep • After you begin to sleep, the brain generates Theta Waves • The deepest parts of sleep are characterized by Delta Waves
Stage 1 NREM (Alpha to Theta): • About 5 minutes • As you transition from wakefulness to early sleep (drowsy stage), you may experience some type of hypnagogic hallucinationsand/or myoclonic jerks • You may hear a loud crash, hear someone call your name, feel a sensation of floating, smell something burning, see a variety of colors • Involuntary muscle spasms
Stage 2 (Theta): • The next 20 minutes • Breathing becomes rhythmical • Some small muscle twitches • Brain activity begins to slow down, sleep talking may occur, and the appearances of sleep spindles • Quick bursts of brain activity that last for a second or two – creation of memories?
Stages of Sleep • Stages 3 and 4 (Delta): • Next 35 Minutes • Heart rate, blood pressure, and breathing drop to their lowest levels • Replenishing chemical supplies, growth hormones released, fortifying the immune system • Stage 4 has more than 50% delta waves
Stages of Sleep • By the time a sleeper has reached Stage 4, they have been asleep for about 60 minutes total. After Stage 4 has been reached, the sleeper cycles back from Stage 3, through Stage 2, and close to Stage 1 in a matter of minutes and enters REM Sleep.
REM Sleep (Paradoxical Sleep): • The brain becomes more active and generates small, fast brain waves • Visual and motor neurons fire during this stage, but voluntary muscle movements are suppressed (paralysis) • Heart rate, blood pressure, and respiration increase, muscles twitches, heightened sexual arousal • The first REM stage lasts about 30 minutes – the first sleep cycle lasts about90 minutes total
REM Rebound Sleep • The less time we spend in REM sleep one night, the longer amount of time we will spend in REM sleep the next night
Beyond the first 90 minutes • Sleepers cycle between NREM and REM sleep throughout the night • Each cycle lasts about 90 minutes • Just before and after REM sleep, you typically change body positions • As the night progresses, Stages 3 and 4 get shorter and REM sleep increases, up to 40 minutes at a time
Sleep Disorders • Sleep Disorders • Insomnia • Apnea • Narcolepsy
Insomnia • A condition in which a person regularly experiences an inability to fall asleep, to stay asleep, or to feel adequately rested by sleep.
Sleep Apnea • A sleep disorder in which the person repeatedly stops breathing during sleep • Carbon-dioxide builds up in the blood, causing a momentary awakening, during which the sleeper snorts or gulps for air
Narcolepsy • A sleep disorder characterized by excessive daytime sleepiness and brief lapses into sleep throughout the day • Though narcoleptics can fall asleep at any time, often times arousals trigger sleep – laughter, anger, surprise, sex • Narcoleptics instantly lose muscular control, and enter REM sleep. The dreams are often terrifying.
Sleepwalking (somnambulism) • Usually within the first three hours of sleep, in Stage 4 • The sleeper typically has the ability to navigate around objects, albeit poorly coordinated and in a stiff, automatic manner
Night Terrors (in Stages 3/4) • Night terrors are usually accompanied by a single, terrifying sensation that awaken the sleeper. Sleepers will usually fall back to sleep without memory of the night terror. • Night terrors may also invoke waking hallucinations
Dreams are a sequence of images, emotions, and thoughts passing through a sleeping person’s mind. Notable for their hallucinatory imagery, discontinuities, and delusions
A lucid dream is the act of consciously perceiving and recognizing that one is dreaming, enabling a more cogent ("lucid") control over the content and quality of the experience.
Dreams are the result of random neural impulses put into a story format by the cortex in order to try and make sense of it. (Activation Synthesis Model)
Dreams are a purposeful way for the brain to try to organize and interpret the overwhelming amount of stimulation that it receives during the day. (Information Processing Theory)
Dreams are manifestations of “unfulfilled desires". Dreams reflect our real passions, aggressions, emotions, etc. They are stored in the unconscious part of the brain and not dealt with in real life. Psychoanalytical Perspective
The manifest content of a dream is the literal storyline and events that occurred • The latent content of a dream is the interpretation of the unconscious drives, wishes, and desires that created the dream
Hypnosis Altered States of Consciousness
Hypnosis • A social interaction in which one person (the hypnotist) suggests to another (the subject) that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur
Posthypnotic Suggestion • A suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized
Posthypnotic Amnesia • A temporary memory loss; supposed inability to recall what one experienced during hypnosis
A Few Clarifications About Hypnosis • Hypnosis is not a state of unconsciousness, nor is it complete mind control • Most everyone can be hypnotized, unless you are resistant to the idea • Hypnosis is a heightened state of awareness and relaxation, combined with a large degree of openness to suggestion
A Few Clarifications About Hypnosis • Age regression therapy (the ability to re-live childhood memories) is very limited in its effectiveness • 25% of Americans believe in reincarnation, though hypnosis does not seem to accurately bring any “past lives” to the surface