Post on 15-Jul-2015
Myers’ PSYCHOLOGY(7th Ed)
Chapter 3
States of Consciousness
James A. McCubbin, PhD
Clemson University
Worth Publishers
Waking Consciousness
Consciousness
our awareness of ourselves and our environments
What is the “dual processing” being revealed by
today’s cognitive neuroscience?
Dual Processing: The Two-Track Mind
Blindsight
Subliminal & blindsight
processing pathway
Threat-related signal processing
(fight/flight response)
Brainstem activated neural alarm
system (alerting/orienting)
Brainstem-amygdala-cortical alarm
system for subliminal signals of fear
Selective Attention
Our conscious awareness processes only a small part of all that we experience. We
intuitively make use of the information we are not consciously aware of.
Inattentional Blindness
Inattentional blindness refers to the inability to see an object or a person in our midst.
Simons & Chabris (1999) showed that half of the observers failed to see the gorilla-suited
assistant in a ball passing game.
Dan
iel
Sim
ons,
Univ
ersi
ty o
f Il
linois
Change Blindness
Change blindness is a form of inattentional blindness in which two-thirds of individuals
giving directions failed to notice a change in the individual asking for directions.
© 1998 Psychonomic Society Inc. Image provided courtesy of Daniel J. Simmons.
Biological Rhythms and SleepCircadian Rhythms occur on a 24-hour cycle and include sleep and wakefulness. Termed our “biological clock,” it
can be altered by artificial light.
Light triggers the suprachiasmatic nucleus to decrease(morning) melatonin from the pineal gland
and increase (evening) it at nightfall.
Sleep & Dreams
Sleep – the irresistible tempter to whom we inevitably succumb.
Mysteries about sleep and dreams have just startedunraveling in sleep laboratories around the world.
90-Minute Cycles During Sleep
With each 90-minute cycle, stage 4 sleep decreases and the duration of REM sleep increases.
Why do we sleep?We spend one-third of our
lives sleeping.
If an individual remains awake for several days, immune function and
concentration deteriorates and the risk of accidents
increases.
Jose L
uis P
elaez, Inc./ C
orb
is
Sleep Hours
Bat -> 20 hours
Baby -> 16 hours
Cat -> 12
Dolphin -> 10 hours
Adult -> 8 hours
Cow -> 4 hours
Giraffe -> 2 hours
Sleep Theories
1. Sleep Protects: Sleeping in the darkness when predators loomed about kept our ancestors out of harm’s way.
2. Sleep Helps us Recover: Sleep helps restore and repair brain tissue.
3. Sleep Helps us Remember: Sleep restores and rebuilds our fading memories.
4. Sleep may play a role in the growth process:During sleep, the pituitary gland releases growth hormone. Older people release less of this hormone and sleep less.
Children are most prone to:
Night terrors: The sudden arousal from sleep with intense fear accompanied by physiological reactions (e.g., rapid heart rate, perspiration) which occur during Stage 4 sleep.
Sleepwalking: A Stage 4 disorder which is usually harmless and unrecalled the next day.
Sleeptalking: A condition that runs in families, like sleepwalking.
Sleep Disorders
Night Terrors and
Nightmares
Night Terrors
occur within 2 or 3 hours of falling asleep, usually during Stage 4
high arousal--appearance of being terrified
0 1 2 3 4 5 6 7
4
3
2
1
Sleep
stagesAwake
Hours of sleep
REM
Sleep Disorders
Insomnia
persistent problems in falling or staying asleep
Narcolepsy
uncontrollable sleep attacks
Sleep Apnea
temporary cessation of breathing
momentary reawakenings
Sleep Deprivation
Effects of Sleep Loss fatigue
impaired concentration
depressed immune system
greater vulnerability to accidents
Sleep Deprivation
2,400
2,700
2,600
2,500
2,800
Spring time change
(hour sleep loss)
3,600
4,200
4000
3,800
Fall time change
(hour sleep gained)
Less sleep,
more accidents
More sleep,
fewer accidents
Monday before time change Monday after time change
Accident
frequency
Why We Dream
3. Physiological Function: Dreams provide the sleeping brain with periodic stimulation to develop and preserve neural pathways. Neural networks of newborns are quickly developing; therefore, they need more sleep.
Why we dream
Satisfy our wishes
Safety valve
File away memories
Information processing
Develop and preserve neural pathways
Physiological function
Make sense of neural static
Reflects cognitive development
Dream TheoriesSummary
Drugs and
Consciousness
Psychoactive Drug a chemical substance that alters perceptions
and mood
Physical Dependence physiological need for a drug
marked by unpleasant withdrawal symptoms
Psychological Dependence a psychological need to use a drug
for example, to relieve negative emotions
Dependence and
Addiction
Tolerance
diminishing effect with regular use
Withdrawal
discomfort and distress that follow discontinued use
Small Large
Drug dose
Little
effect
Big
effect
Drug
effect
Response to
first exposure
After repeated
exposure, more
drug is needed
to produce
same effect
Depressants
Depressants are drugs that reduce neural activity and slow body functions. They include:
1. Alcohol
2. Barbiturates
3. Opiates
StimulantsStimulants are drugs that excite neural activity and speed up body functions. Examples of stimulants are:
1. Caffeine
2. Nicotine
3. Cocaine
4. Ecstasy
5. Amphetamines
6. Methamphetamines
Why Do People Smoke?
3. Nicotine takes away unpleasant cravings (negative reinforcement) by triggering epinephrine, norepinephrine, dopamine, and endorphins.
4. Nicotine itself is rewarding (positive reinforcement).
Psychoactive Drugs
Ecstasy (MDMA) synthetic stimulant and mild hallucinogen
both short-term and long-term health risks
LSD lysergic acid diethylamide
a powerful hallucinogenic drug
also known as acid
THC the major active ingredient in marijuana
triggers a variety of effects, including mild hallucinations
Psychoactive Drugs
Influences on Drug Use
The use of drugs is based on biological, psychological, and social-cultural influences.
Influence for Drug Prevention and Treatment
1. Education about the long-term costs
2. Efforts to boost people’s self-esteem and purpose
3. Attempts to modify peer associations and teaching refusal skills