Consciousness

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Chapter 6

• Consciousness

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Consciousness

• Definition - subjective awareness of internal and
  external stimuli
• Examples
• Awareness of external events
• Awareness of internal sensations
• Awareness of your self as the unique being having
  these experiences
• Awareness of your thought about these experiences

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Attention

• Definition The internal processes people use to
  set priorities for mental functioning.
• You can only be consciously aware of those
  stimuli to which you pay some attention.
• Limitations in brain and nervous system resources
  mean that attention must be selective. We cant
  pay attention to everything.
• Too much attention to stimuli would mean that you
  would be attending to many irrelevant things in
  the environment.

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Dichotic Listening

• Listening to independent auditory input in each
  ear at the same time.
• The subject must either listen to one message or
  switch back and forth
• If subjects are asked to repeat on of the
  messages aloud, they usually process the other
  one poorly.

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Cocktail Party Effect

• We dont just shut out the rest of the world when
  we focus on a stimulus
• At a cocktail party, you may not be able to
  describe what the people next to you were talking
  about.
• But, if someone across the room suddenly says
  your name, your attention will probably shift to
  that stimulus.
• Suggests that we may be monitoring more stimuli
  than we realize.

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Disorders of Attention

• Visual Neglect caused by damage to right
  parietal lobe.
• Tendency to ignore things that appear toward the
  left side of the body.
• As if the entire left visual field has
  disappeared.
• They may not shave, dress, wash, or apply make-up
  to left side of the face/body.

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Attention Deficit Disorder

• Difficulty concentrating and sustaining attention
• Prevalence is about 3 to 5 of all children
• Hyperactive and impulsive behavior
• Cause is not known. Several regions of brain are
  implicated, including frontal lobes.
• Treatment is medication and directed training.
• May be overdiagnosed

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Circadian Rhythms

• Circadian Rhythms 24 hour biological cycles found
  in humans and many other species
• Accompanied by fluctuations in temperature,
  hormone regulation, blood pressure, etc.
• If left without light/dark cycle people will
  drift to a 25-hour cycle

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SLEEP STAGES

• Stage 1
• Theta Waves, irregular, breathing slows, light
  sleep, easily awakened, lasts about two minutes,
  may have sensory experience without stimulus
• Sleep Stage 2
• About 20 minutes long, characterized by sleep
  spindles and mixed EEG activity
• Stages 3 4
• About 30 minutes long, hard to awaken,
  characterized by delta waves
• REM
• Deep stage of sleep marked by rapid eye movement,
  high-frequency brain waves, and dreaming

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SLEEP EEG RECORD
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Typical Sleep Architecture
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Sleep Problems

• Reported sleep problems increase with age

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R.E.M. SLEEP

• First R.E.M. period occurs about 90 minutes after
  onset of sleep and repeats about every 90
  minutes.
• Duration of REM sleep increases as sleep cycle
  continues.
• Physical correlates rapid, irregular eye
  movements, sexual arousal (erection, vaginal
  lubrication), loss of muscle tone.
• Also called Paradoxical sleep because EEG
  resembles waking pattern, but person is deeply
  asleep. Easier to awaken than other stages.
• Dreaming highly correlated with R.E.M., but not
  exclusive to R.E.M.

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Function of Sleep

• Two Theories
• Restorative-sleep promotes physiological
  processes that rejuvenate the body each night.
  Not a whole lot of evidence to support this
  theory.
• Circadian-sleep is an aspect of circadian rhythms
  regulated by neural mechanisms that are a product
  of evolution. Sleep evolved as a protective
  mechanism to prevent people from wandering into a
  hostile world where predators have the advantage.

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Dreaming

• What is a dream?
• Dreams are mental experience during REM sleep
  that has a story-like quality, include vivid
  visual imagery, are often bizarre, and are
  regarded as perceptually real by the dreamer
• What do people dream about?
• Most dreams unfold in familiar settings with a
  cast of characters dominated by family, friends,
  and colleagues with a sprinkling of strangers
• Generally what people dream about is affected by
  what is going on in their lives

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Dreaming

• The Function of Dreaming
• Wish Fulfillment (Freud)-manifest and latent
  contents
• Information Processing (Cartwright)-the need to
  continue processing the days activities
• Activation synthesis hypothesis (Hobson and
  McCarley)-triggered by neural activity from the
  brainstem.

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Figure 5.9Three theories of dreaming.Dreams can
be explained in a variety of ways. Freud stressed
the wish-fulfilling function of dreams.
Cartwright emphasizes the problem-solving
function of dreams. Hobson and McCarley assert
that dreams are merely a by-product of periodic
neural activation.
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Insomnia

• Chronic difficulty in initiating or maintaining
  sleep
• Difficulty in falling asleep
• Difficulty in remaining asleep
• Persistent early-morning awakening
• Lasts at least one month

Prevalence - about 15 of adults report severe or
frequent
insomnia and another 15 report mild or
occasional insomnia Causes - Excessive anxiety,
emotional problems, stress, health problems, use
of stimulant drugs, learned patterns
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Other Dyssomnias

• SLEEP APNEA person repeatedly stops breathing
  during sleep, lasting up to a minute, causing
  person to wake up and gasp for breath. Person
  wakes up feeling tired. Elephant man died of
  sleep apnea.
• Narcolepsy person is seized by sudden urge to
  sleep. They move from a waking state immediately
  into a R.E.M. period, losing consciousness and
  muscle tone.

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Parasomnias

• Night terrors mostly occur in children, tend to
  go away with age. Child sits up in bed,
  screaming, unresponsive to stimuli. Usually occur
  in NREM sleep, unlike nightmares, which occur
  during REM.
• Sleepwalking person gets up and wanders about.
  Mostly seen in children and declines with age.
  Also occurs during NREM sleep.

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Figure 5.8The vicious circle of dependence on
sleeping pills.Because of the bodys ability to
develop tolerance to drugs, using sedatives
routinely to cure insomnia can lead to a
vicious circle of escalating dependency as
larger and larger doses of the sedative are
needed to produce the same effect.
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SLEEP DISORDERS
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Altering Consciousness with Drugs

• Principle Recreational Drugs And Their Effects
• Opiate narcotics are drugs derived from opium
  that are capable of relieving pain. Morphine,
  heroin
• Depressants are drugs that tend to decrease
  central nervous system activation and behavioral
  activity. Alcohol, barbiturates, tranquilizers.
• Stimulants are drugs that tend to increase
  central nervous system and behavioral activity.
  Amphetamine, cocaine, caffeine
• Hallucinogens are a diverse group of drugs that
  have powerful effects on mental and emotional
  functioning, marked most prominently by
  distortions in sensory and perceptual experience
• Cannabis is the hemp plant from which marijuana,
  hashish, and THC are derived.

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Drug Tolerance

• Tolerance means that the body has adapted to the
  presence of the drug over time. Increased doses
  of the drug are needed in order to get the
  desired effect.

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Drug Dependence

• Dependence physical or psychological need for
  continued use of a drug.
• Physical-showing a withdrawal syndrome once
  removed from the drug regimen
• Sweating
• Vomiting
• Tremors
• Heart Rate Changes
• Psychological - an intense emotional or mental
  need for the drug. Person feels irritable,
  anxious when drug is withdrawn, but not
  necessarily physically ill.

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Factors Influencing Drug Effects

• Age
• Mood
• Motivation
• Personality
• Previous experience with the drug
• Tolerance
• Body Weight
• Physiology
• Dose and potency of drug
• Method of administration
• Expectation /Setting

• Not everyone will have the same response to the
  same drug. To the left are some reasons why

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Mechanisms of Drug Action

• Amphetamines and Cocaine increase release and
  block reuptake of both dopamine and
  norepinephrine
• Depressants and alcohol increase GABA activity
• Opiates bind opiate receptors and increase
  dopamine activity
• Hallucinogens (eg., LSD) and Marijuana
  mechanisms are unknown

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Figure 5.12Amphetamines and neurotransmitters.Li
ke other drugs, amphetamines alter
neurotransmitter activity. Depicted here are two
ways in which amphetamines appear to increase
dopamine (DA) and norepinephrine (NE) activity.
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Drugs and Physical Health

• Overdose-consumption of a lethal quantity of drug
• Direct Effects - tissue damage
• Ex nasal membranes deteriorate when cocaine is
  snorted
• Alcohol and liver disease (cirrhosis)
• Health-impairing behavior (indirect effects)
• Ex people on alcohol/sedatives who drive can
  injure themselves and others because of slowed
  reaction time and reduced motor coordination

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Hypnosis

• Founded by Franz Anton Mesmer (1734-1815)
• The term Hypnosis was coined in 1843 by James
  Braid who proposed to use it as an anesthetic
• Powerful pharmaceutical anesthetics were
  introduced and the excitement for hypnosis
  dwindled
• used in the medical community to assist patients
  and by entertainers for our amusement

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Effects of Hypnosis

• Anesthesia perhaps for some minor surgical
  procedures, but not anything major.
• Sensory distortions and hallucinations
• Disinhibition
• Posthypnotic suggestions and amnesia seem more
  related to role-playing and following the lead of
  the hypnotist.

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Theories of Hypnosis

• Role Playing-because no physiological changes are
  associated with hypnosis, some conclude that
  hypnosis produces a normal state of consciousness
  in which suggestible people act out the role of a
  hypnotized subject.
• Altered State of Consciousness-hypnosis creates a
  dissociation, or splitting off of mental
  processes into two separate, simultaneous streams
  of awareness. One is in contact with the
  hypnotist while the other is hidden.

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Meditation-trained attention to heighten
awareness and bring mental processes under
greater voluntary control

• Physiological and Psychological Effects
• Increased alpha and theta waves in EEG recordings
• Heart rate, respiration, oxygen consumption, and
  carbon dioxide elimination decline
• Reduce anxiety, improve mood, reduce drug abuse,
  improve physical health
• While the mechanisms of these effects are argued,
  it is safe to say that it works effectively as a
  relaxation technique