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REM Sleep
Brain activity is heightened as well as body activity
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Stages of Nrem Sleep
- Stage 1 - transitional stage in which you gradually disengage from the sensations of the surrounding world. Alpha brain waves are replaced by even slower Theta brain waves. Lasts a few minutes
- 2 - represents the onset of true sleep. Defined by the appearence of sleep spindles and k complexes. Brain activity continues to slow down. Theta waves are dominant but larger, slower brain waves (Delta brain waves) begin to emerge. 15 - 20 minutes
- Stages 3 and 4 - "slow wave sleep" both similar to eachother. defined by the amount of delta brain wave activity.
- D.B.W activity is more than 20% = Stage 3 when it is greater than 50% = stage 4
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Consciousness
A person's immediate awareness of thoughts, sensations, memories, and the world around them.
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William James description
William James described consciousness as a stream or river (always changing, consciousness is perceived as unified and unbroken, much like a stream)
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Circadian Rhythms
Biological processes that systematically vary over a 24 hour period
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Melatonin
- A hormone manufactured by the pineal gland that produces sleepiness
- As sunlight decreases triggers cause an increase in this hormone
- Increased levels make you sleepy and reduce activity levels
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Suprchiasmatic nucleus
A cluster of neurons in the hypothalmus that governs the timing of circadian rhythms
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Sunlight
Sets the suprchiasmatic nucleus so that it keeps ciradian cycles synchronized and operating on a 24 hour schedule
Suppresses melatonin levels as this sets
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sleep/wake cycles out of synch
1. people drift to the natural rhythm of the SCN which is a 25 hour day not 24 and go to sleep 1 hour later
2. Ciradian Rhythms lose their normal synchroniztion with each other (normally the sleep/wake cycle, body temp., and melatonin cycles are closely coordinated but in the absence of enviromental cues, they become desynchronized.
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REM Sleep
- type of sleep during which rapid eye movement occurs
- Rapid eye movement and dreaming usually occur and voluntary muscle activity is suppressed
aka active sleep or paradoxical sleep
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NREM
Quiet typically dreamless sleep in which rapid eye movements are absent.
aka quiet sleep
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NREM
Physiological function and brain activity slow down
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Rebound
Phenomeon in which a person who is deprived of REM sleep, greatly increases the amount of time spent in REM sleep at the 1st opportunity to sleep uninterrepted. This suggest that the brain needs to make up for missing sleep components. We need full range of sleep stages.
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Restorative Theory
- suggests that sleep promotes physiological process that restores and rejuvenate the body and mind
- NREM - restoring the body
- REM - restoring the mind
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Insomnia
A condition in which a person regularly experiences an inability to fall asleep, stay asleep or to feel adequately rested by sleep
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Sleep Apnea
the sleeper repeatedly stops breathing during the nite. CO2 builds in the blood causing a momentary wakening. Skin may turn blue. may last for up to 10 seconds
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REM Sleep Behavior Disorder
the brain fails to suppress voluntary muscle movements during sleep. Dreamer acts out their dreams. May be early symptom of a neurological disorder; pakinsons disease
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Narcolepsy
- excessive daytime sleepiness adn brief lapses into sleep throughtout the day. Cataplexy - sudden loss of voluntary muscle strength and control
- Modafinil may help with symptoms
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Most common sleep compaint amoung adults
Insomnia
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Alcohol / Sleep medication
helps temporarily but they both disrupt normal sleep cycles, including REM
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Night terrors
occur during stages 3 or 4, more intense than a nightmare. Sharply increased physiological arousal (restlessness, sweating, or rapid heart rate) tend to be brief
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Nightmare
a frightening or unpleasant anxiety dream that occurs during REM sleep
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REM role in memory
- primary visual cortex and the frontal lobes are shut down during REM. These are responsible for registering visual info from the retinas of the eye. Also resp. for higher level cognitative processes (reasoning, planning, and integrating perceptual info)
- Sleeper is cut off from external world and the brain centers most involved in rational thought
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Active ares of the brain during REm
Amygdala and hippocampus which are involved in emotion, motivation, and memory. other parts of the brains visual system that are involved in generating visual images are active
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Common themes of dreams
- Most dreams are a reflection of everyday life - daily concerns of dreamer
- include more neg events than positive around the world
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Why cant we remeber dreams
- changes in brain chemistry and functioning that occurs during sleep, fails to support info. processing and storage of new info. (dreams)
- Neurotransmitters (dopamine, Serotonin, and norepinephirne) needed to acquire new memories are greatly reduced during REM sleep
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Freuds theory of dreams - Wish fulfillment
- Feelings of unacceptable consious instincts like sexual and aggresive thoughts are pushed into the unconscious or repressed - these feelings resurface during dream
- " disguised fulfillments of repressed wishes"
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Activation - synthesis model
- theory that brain activity during sleep produces dream images (activation) which are combined by the brain into a dream story
- -Dreaming is essentially the brain synthesizing and integrating memory fragments, emotions, and sensations that are internally triggered
- - various memories or sensations that are internally generated by the brain
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Hypnosis
a cooperative social interaction in which the hypnotized responds to suggestions with changes to perception, memory and behavior.
Limits of - not against someone will, cant make you perform behaviors that are contrary to a persons values, and cant make you stronger that your physical capabilities
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Accuracy of rececalled memories during age regression
hypnotic subjects combine fragments of actual memories with fantistic and ideas about how children of a certain age should behave
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Meditation
sustained concentration techniques that focus attention and heightened awareness
relaxation tech. that relieve stress and improved cardiovascular health
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Dependence
body and brain chemistry have physically adapted to a drug
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Drug rebound
withdrawl symptoms that are the opposite of a physically addictive drugs action
ex - withdrawal from caffening = depression
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Drug Abuse
recurrent drug use that results in the disruption of academic, social, or occupational functioning or in legal or psychological problems
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Depressants
- Alcohol, Barbiturates, and tranquilizers
- depress or inhibit CNS activity. produces drowsiness, sedation or sleep
- relive anxiety and lower inhibitions
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Opiates
- Morphine, heroin, cocaine
- narcotics
- relieve pain and produce euphoria
- mimicks the brains endorphins ( natural pain killers)
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Stimulants
- Caffeine, nicotine, amphetamines, cocaine
- mildly addicting, tend to increase brain activity
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Most widely used psychoactive drug in the world
Caffeine
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Most addictive drug affects
Dopamine
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