ch.4: states of consciousness

consciousness

awareness of internal (pain, hunger, & thirst) & external stimuli (light from sun, warmth in a room, etc)

biological rhythms

internal rhythms of biological processes that occur on a regular cycle, such as sleep-wake cycles, hormone release, and body temperature

what is the major center for homeostasis

hypothalamus

circadian rhythm

• exists in plants, animals, insects, & human beings

• our internal clock, controlling our temperature and wakefulness in 24-hour cycles

• easily adapted to external social cues (clocks, etc)

  • can be good & bad thing

suprachiasmatic nucleus (SCN)

• hypothalamus; responds to light/dark

  • regulates the pineal glands secretion of melatonin @ night

• light in the morning causes melatonin to fall

• there are other clocks, but we don’t know where they are located

internal desynchronization

• when our normal routine changes, our circadian rhythms may be thrown out of sync

• ex: jet lag

sleep debt

can result in decreased mental alertness & cognitive functioning & produce depression like symptoms

physical functions of sleep

• the brain may remove metabolic waste products

• repairs body tissues

• conserve or replenish energy sources

• strengthen the immune system

• recover abilities lost during the day

psychological functions of sleep

• sleep may be necessary for consolidation

• sleep may assist in problem solving

  • taking an exam w insufficient amount of sleep can be disastrous

consolidation

a process associated w stored memories making them durable & stable

sleep systems

• sleep is regulated by 2 general neurological systems:

  • system 1: nuclei in pons/midbrain junction

  • system 2: pons & medulla

• during wakefulness, both systems are active

• during slow wave (delta), there is a decrease in both systems

• during REM, sleep system 1 is extremely active while system 2 is completely turned off

sleep stages

• awake: low voltage, high frequency

• stage 1: low voltage, mixed frequency

• stage 2: sleep spindles & K complexes → muscle jerking

• stage 3: mostly slow waves

• stage 4: slow waves

• REM: rapid eye movement, low voltage, mixed frequency, & muscle atonia

  • phases get longer as night progresses

sleep problems and disorders

• insomnia

• parasomnia

insomnia

• chronic difficulty in either falling or staying asleep

• 30-50 million people suffer from it

• most common disorder

• many methods to help sufferers include:

  • stress management

  • CBT

  • change in problematic behaviors

parasomnia

group of sleep disorders in which unwanted, disrupted motor activity &/or experiences during sleep play a role

select parasomnias

• sleep walking

• sleep related eating disorder

• restless leg syndrome

• sleep talking

• REM sleep behavior disorder

• sleep paralysis

• exploding head syndrome

sleep walking

usually occurs during delta wave sleep (stage 4)

sleep related eating disorder

occurs when the person eats at night while asleep

restless leg syndrome

usually occurs when the person is trying to fall asleep

• they feel like they have to get up & walk

• symptoms: burning, cramping, pain, numbness, itching, tingling, aching, & crawling

sleep talking

often seen in children but also adults

• in some cases, the person will speak coherently, while others just mumble

REM sleep behavior disorder

occurs when muscle paralysis doesn’t occur

• occurs during REM stage of sleep

• brain shuts down muscle movement

sleep paralysis

usually occurs when someone begins to wake up & finds that they cannot talk or move

• may be accompanied by pressure on the chest & hallucinations

• if the person waits a few mins, it subsides

exploding head syndrome

occurs during sleep when person imagines a loud bang or similar sound

• it often wakes the person right up

• generally during the 1st 20 mins of sleep

sleep apnea

• individual stops breathing for a few moments

• more often in older, overweight males

• may be caused by a blockage of air or a failure of the brain to control respiration (central sleep apnea)

• ratio: 1 woman to 10 men

narcolepsy

• often develops in adolescence

• person falls asleep for 5-30 mins

• cause isnt well understood

• some develop cataplexy (brings on paralysis of REM)

  • person may suddenly collapse to the floor although still awake

sudden infant death syndrome

• an infant stops breathing during sleep & dies

• infants under 12 months are most at risk

• boys are more at risk than girls

types of dreams

• NREM

• REM

• nightmare

• night terror

• lucid dream

dream

state of consciousness that occurs mostly during REM sleep & is accompanied by vivid visual imagery

NREM dreams

dreams are less visual & more thought oriented

REM dreams

vivid, action oriented, & often emotionally evoactive

nightmare

frightening dream occurring during REM sleep

night terror

occurs in NREM (usually stage 4) in which the individual sits up, lets out a blood curdling scream, speaks incoherently, & quickly falls back to sleep

• can outgrow it but not always

lucid dream

p can actually “direct” (change) the dream the dreamer becomes aware that she/he is dreaming, & in some cases

people who came up with dream theories

• freud: wishfulfillment

• cartwright: dreams reflect life events

• hobson: activation synthesis hypothesis

wish fulfillment dream theory

• created by frued

• manifest content (obvious aspects of the dream)

• latent content (symbolic aspects of the dream)

• penis symbolized as a : snake, dagger, & umbrella

• vagina symbolized as a: tunner or cave

• human body symbolized as a house

• sex & aggression was a biggie for frued

dreams reflect life events theory

• created by cartwright

• dreams are problem focused

• believed the symbols & metaphors in a dream do not disguise its true meaning

• often dreams reflect current concerns we’ve been having

• dreams may also provide an opportunity to resolve problems

activation synthesis hypothesis dream theory

• created by hobson

• believed dreams mean nothing

• pons fires away during REM & sends messages to the higher cortical centers especially vision & emotional areas

  • this is a simple biological process that has no psychological meaning

• cortex tries to make sense (synthesizing) of these “firings”

• logical thought & sensations are shut down giving rise to the emotional, hallucinatory, & illogical nature of the dream

drug

any substance that alters normal biological processes

psychoactive drug

a drug that alters behavior, thought, or emotions by altering the biochemical reactions in the nervous system

psychological dependence

need to take a drug to cope w problems or stress

physical dependence on a drug

• tolerance

• withdrawal

tolerance

a physiological state where a greater amount of the drug is needed to produce the same effect

withdrawal

a physiological state where the individual experiences undesirable intense pain & craving when a drug is w drawn

pleasure principle

brain registers pleasure (ex: drugs, monetary reward, sexual encounters, or satisfying meals) the same way via dopamine in the nucleus accumbens

dopamine

• not only contributes to the experience of pleasure but also plays a role in learning & memory

• it interacts w glutamate (neurotransmitter) to take over brains system of reward related learning

depressants

• alcohol

• sedative hypnotics:

  • barbituates

  • Benzodiazepines

stimulants

• cocaine

• amphetamine

• benzedrine, dexedrine

• caffeine

• nicotine

hallucinogens

• cause powerful changes primarily in sensory perception, including intensification of perceptions & inducement of illusions & hallucinations

• LSD, PCP, & MDMA (ecstasy)

cannabis

• causes a mixture of halucinogenic, depressant, & stimulant effects

• hashish (most powerful drug produced from hemp plant)

• ganja (moderately powerful)

• marijuana (weaker derivative)

opiates

• opium

• morphine

• heroine

• synthetic drugs

  • methadone