Consciousness is the
awareness of internal
and external stimuli
The contents of consciousness are
continually changing
It moves
It flows
It fluctates
It wanders
When you are asleep your consciousness
moves through a series of transitions
Constant change and shifting seem to be apart of the essential nature of consciousness
The most commonly used indicator
of variations in consciousness has
been the EEG
(the EEG records activity
from broad swaths of
the cortex)
EEG also summarizes
the rhythm of cortical
activity in the brain in
terms of line tracings
called brain waves
Biological Rhythms
Periodic fluctuations in
physiological functioning
Circadian rhythms are particularly
influential in the regulation of
sleep
Daily exposure to light readjusts
people's biological clocks
When exposed, some receptors in the retina send direct inputs to a
small structure in the hypothalamus called the suprachiasmatic
nucleus
Getting out of sync with your circadian
rhythms also causes "jet leg"
A promising line of research has focused on
giving small doses of the hormone
melatonin, which appears to regulate the
human biological clock
Sleep
EEG pattern in sleep and wakefulness
Awake
Low voltage, high frequency beta waves
Drowsy
Alpha waves prominent
Stage 1 Sleep
Theta waves prominent
Stage 2 Sleep
Sleep spindles and mixed EEG activity
Slow-Wave Sleep (stage 4 and 4 sleep)
Progressively more delta waves
REM sleep
Low-voltage, high-frequency waves
REM sleep is a relatively
deep stage of sleep marked
by rapid eye movements;
high-frequency,
low-amplitude brain waves;
and vivid dreaming
It is such a special stage of sleep that the
other four stages are often characterized
simply as non- REM sleep
Non-REM sleep consists of sleep stages 1 through 4, which are marked by an
absence of REM's, relatively little dreaming, and varied EEG activity
Insomnia
Most common sleep disorder
Refers to chronic problems
in getting adequate sleep
Three basic
patterns:
1) difficulty in falling asleep
2) difficulty in remaining asleep
3) persistent early-morning
awakening
Causes:
excessive
anxiety
tension
emotional
problems
health problems
significant
stress
Treatment:
benzodiazepine sedatives
Dalmane Halcion
Restoril
non benzodiazepine sedatives
Ambeian
Sonata
Lunesta
(sedatives can be a poor long term solution for insomnia because it can
lead to drug overdose etc)
Sleep
deprivation
Occurs when people make do with
substanitially less sleep than
normal people over a period of
time
Can impair
Individuals attention
Reaction time
Cognitive speed and accuracy
motor coordination
decision making
Selective deprivation of slow wave sleep makes
subjects want to have longer periods of REM sleep
Studies suggest that REM and slow wave sleep contribute to firming up learning that
takes place during the day
Other
Sleep
Problems
Narcolepsy
A disease marked by sudden and
irresistible onsets of sleep during normal
waking periods
Night terrors
(sleep terrors)
Abrupt awakenings from NREM sleep, accompanied
by intense automatic arousal and feelings of panic
Sleep
Apnea
Involves frequent, reflexive
gasping for air that awakens a
person and disrupts sleep
Nightmares
Anxiety-arousing dreams that lead to
awakening, usually from REM sleep
Somnambulism
(sleep
walking)
Occurs when a person
arises and wanders about
while remaining asleep
REM sleep
behaviour
disorder
By marked potentially troublesome dream
enactments during REM periods
Dreams
What people dream
about is affected by
what is going on in
their lives
Freud noticed long ago that the contents of waking life often tented to spill into dreams
The content of dreams can also be affected by stimuli
experience while one is dreaming
Sometimes people may realize they are
dreaming while still in the dream state (lucid
dreaming)
Lucid dreams are dreams in which
people can think clearly about the
circumstances of waking life and the
fact that they are dreaming, yet they
remain asleep in the midst of a vivid
dream
Theories of Dreaming
Sigmund
Freud
Believed that the
principle of
dreams is wish
fulfillment
Catwright
and
Lamberg
Proposed that dreams
provide an opportunity to
work through everyday
problems
Hobson
and
McCarley
Argue that dreams are simply the
by-product of bursts of activity
emanating from subcortical areas in
the brain
J. Allan Hobson
Proposes that dreams are
side effects of the neural
activity that produces
"wide-awake" brain waves
during REM sleep
Hypnosis
Systematic procedure
that typically produces a
heightened state of
suggestibility
May also lead to
passive relaxation,
narrowed attention,
and enhanced fantasy
Hypnotic
Phenomena
1) Anesthesia
hypnosis can be a surprisingly
effective anesthetic in the
treatment of both acute and
chronic pain
2) Sensory Distortions and Halluctions
May be led to
experience
auditory or visual
hallucinations
May also
have their
sensations
distorted
3) Disinhibition
Can sometimes reduce inhibititions
that would normally prevent subjects
from acting in ways that they would
normally see as socially undesirable
4) Posthypnotic Suggestions and Amnesia
May influence a
subjects later
behaviour
May or not may not
forget what had
happened during the
processe
Meditation
Refers to a family of practices that train
attention to heighten awareness and bring
mental processes under greater voluntary
control
Practiced
throughout
history as an
element of all
religious and
spiritual
traditions
Approaches to meditation cna be classified into
two main styles that reflect how attention is
directed
1) Focused Attention
Attention is concentrated on a
specific object, sound or
bodily sensation
2) Open Monitering
Attention is directed to the contents of
one's clear moment-to-moment experience
in a nonjudgmental and nonreactive way
Some Long Term Benefits
Lower levels of "stress hormones"
Enhanced
immune
response
Improves
mental health
Reduces
anxiety
and drug
abuse
Beneficial effects on
blood pressure
Reduced
rumination
Working memory
and focus
Improves self esteem
Cognitive flexibility
and relationship
satisfaction
Improves mood and one's sense of control
Altering Consciousness with Drugs
The drugs that people use
recreationally are
psychoactive.
Psychoactive drugs are chemical
substances that modify mental,
emotional, or behavioural functioning
Generally, people prefer drugs that elevate their mood or produce other pleasurable alterations in conciousness
Primary Abused Drugs
Narcotics (or opiates) : drugs
derived from opium that are
capable of relieving pain
Sedatives : Sleep inducing
drugs that tend to decrease
the central nervous system
activation and behavioural
activity
Stimulants :
Drugs that tend
to increase
central nervous
system
activation and
behavioural
activity
Hallucinogens : Diverse group of
drugs that have powerful effects
on mental and emotional
functioning
Cannabis : A hemp plant from which
marijuana, hash, and THC are derived
Alcohol : Variety of
beverages containing
ethyl alcohol
MDMA (ecstasy) : Compound
drug related to both
amphetamines and
hallucinations, especially
mescaline
The impact on any drug depends in
part on the users age, mood,
motivation, personality, previous
experience, body weight, and
physiology
The dose and potency of the drug, the method of
administration, and the setting in which a drug is taken also
influence its effects