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Lecture

LAW 122 Lecture Notes - Circadian Rhythm, David Chalmers, Unconscious Mind


Department
Law and Business
Course Code
LAW 122
Professor
Eric Ball

Page:
of 6
Chapter 6 States Of Consciousness
State of consciousness= a pattern of subjective experience, a way of experiencing internal and
external events
Altered state of consciousness- refers to variation from our normal walking state. While
daydreaming passing from wakefulness to sleep may experience vivid images and our nighttime
dreams can seem just as real and emotionally charged as our waking perception
Philosopher David Chalmers notes conscious experience is at once the most familiar thing in the
world and the most mysterious
The Puzzles Of Consciousness
Consciousness=our moment-to-moment awareness of ourselves and our environment. Among its
characteristics, consciousness is:
o Subjective and private- other people cannot directly know what reality is for you, nor can
you enter directly into their experiences
o Dynamic (ever changing)- we drift in and out of various states throughout each day
Although the stimuli of which we are aware constantly change we typically experience
consciousness as continuously flowing “stream” of mental activities rather than a
disjointed perceptions and thoughts.
o Self- Reflective and Central to our sense of self- the mind is aware of its own
consciousness thus no matter what your awareness is focused on you can reflect on the
fact that you are the one who is conscious of it
Consciousness is intimately connected with the process of selective attention
Selective attention focuses conscious awareness on some stimuli to the exclusion of others
Measuring States Of Consciousness
Self report- most common measure in which people describe their inner experiences. Offers the
most direct insight into a person’s subjective experiences but they are not always verifiable.
Physiological measures- establish the correspondence between bodily states and mental; processes
Behavioral measures objective but must still infer the persons state of mind
Levels of Consciousness: Psychodynamic and cognitive Perspectives
Sigmund Freud 3 levels of awareness:
o Conscious mind- contains thoughts perceptions and other mental events of which we are
currently aware
o Preconscious- mental events are outside current awareness but can easily be recalled
under certain conditions
o Unconscious events cannot be brought into conscious awareness under ordinary
circumstances
Some unconscious content is kept out of conscious awareness because it would arouse anxiety and
guilt or other negative emotions
Research strongly supports Freud’s general premise: nonconscious process influence behavior
The Cognitive Viewpoint
Cognitive psychologists reject the notion of an unconscious mind driven by instinctive urges and
repressed conflicts.
They view conscious and unconscious mental life as complementary forms of information
processing
Daniel Reisberg= unconscious mental activity is not an adversary to the conscious mind. Instead
the cognitive unconscious functions as a sophisticated support service working in harmony with
our conscious thoughts
Controlled Versus Automatic Processing
Controlled (effortful) Processing= the voluntary use of attention and conscious effort. Example-
planning a vacation
Automatic Processing= occurs most often when we carry out routine actions or well learned tasks
In conscious thought becomes less active
Automatic processing has a key disadvantage- It can reduce our chances of finding new ways to
approach problems
Controlled processing is more flexible and open to change
Divided Attention
Automatic processing facilitates divided attention
Divided Attention= the ability to perform more than one activity at the same time
Divided attention has limits and is more difficult when tasks require similar mental resources
The Emotional Unconscious
Strong negativity or negative subliminal messaging can influence negative emotion and strong
positive messaging= positive feelings
The Modular Mind
Propose the mind is a collection of largely separate but interacting modules
These modules are information processing subsystems or networks within the brain that perform
tasks related to sensation perception memory problem solving emotion motor behavior and so on
Circadian Rhythms: Our Daily Biological Clocks
Every 24 hours our body temperature certain hormonal secretions and other bodily functions
undergo a rhythmic change that affects our mental alertness and readies our passage back and
forth between stated of wakefulness and sleep. These daily biological circles are called circadian
rhythm from the Latin word circa “around” and dia “day”
Keeping Time: The Brain And Environment
Most circadian rhythms are regulated by the brain’s superchiasmatic nuclei (SCN) which are
located in the hypothalamus
SCN neurons have a genetically programmed cycle of activity and inactivity functioning like a
“biological clock” they link to the tiny pineal gland which secretes melatonin- a hormone that has
a relaxing effect on the body
SCN neurons become active during daytime and reduce the pineal glands secretion of melatonin
raising your body temperature and heightening alertness
At night SCN neurons are inactive allowing melatonin levels to increase and promoting relaxation
and sleepiness
Most people drift into a longer natural cycle of about 24.2 to 24.8 hours called a free running
circadian rhythm
Because their free running circadian rhythm is desynchronized with the 24 hour day night cycle
participants in these isolation studies tend to go to bed and wake up later each day
Blind children and adults with sensitive eyes to light may also experience the free running
circadian rhythm
Environmental Disruptions Of Circadian Rhythms
Seasonal Affective Disorder- is a cyclic tendency to become psychologically depressed during
certain months of the year
Rotating Shift work
Sleep And Dreaming
Circadian do not regulate sleep directly. Rather by decreasing nighttime alertness they promote a
readiness for sleep and help to determine the optimal period when we can sleep soundly
Stages Of Sleep
Beta waves= when you are aware and alert. Beta waves have a high frequency of about 15- 30
cycles per second or cps. But a low amplitude or height .
As you close your eyes feeling relaxed and drowsy your brain waves slow down and ALPHA
WAVES occur at about 8- 12 cycles per second
Stages 1 to 4
Theta waves- 3.5- 7.5 cycles per second. This is a part of stage one a form of light sleep from
which you can easily be awakened
As sleep becomes deeper SLEEP SPINDLES- periodic one to two second bursts of rapid brain
wave activity (12- 15 cycles per second)
Sleep spindles indicate that you are now in stage 2- your muscles are more relaxed, your breathing
and heart rate are slower and you are harder to awaken
Sleep deepens when you’re in stage 3- marked by regular appearance of very slow (0.5- 2 cycles
per second) and large DELTA WAVES. As time passes they occur more often and when delta
waves DOMINATE the EEG pattern you have reached stage 4
Stage 4- together stage 3 and 4 are often referred to as SLOW WAVE SLEEP- your body is
relaxed, activity in various parts of your brain has decreased and you are hard to awaken. After 20-
30 mins of stage 4 your EEG pattern changes as you go “back through” stages 3 and 2, spending a
little time in each. Overall within 60 to 90 mins of going to sleep you will have completed a cycle
of 1-2-3-4-3-2. At this point a remarkably different sleep stage ensues.
REM Sleep
REM sleep= every half minute or so, bursts of muscular activity caused the sleepers’ eyeballs to
vigorously move back and forth beneath their closed eyelids. Because of these rapid eye
movements (REMs), this stage is called REM sleep
When this occurs a dream is almost always dreamt
During REM , the brain sends signals making it more difficult for voluntary muscles to contract
REM SLEEP PARALYSIS= paralyzed and unable to move and because of this REM is
sometimes called paradoxical sleep- your body is highly aroused and yet it looks like you are
sleeping peacefully because you move so little
REM MAKES THE DREAM MORE REAL BECAUSE YOU AREUSING MENTAL
ACTIVITY AND YOU ARE ABLE TO FEEL TOUCH SMELL TASTE ETC.
Sleep thoughts= some of the mental activity that occurs during non REM sleep has even been
referred to as sleep thoughts because of the close resemblance to daytime thinking to REM dreams
Each cycle through the sleep stage takes about 90 minutes
Getting A Night’s Sleep Brain And Environment
Areas at the base of the forebrain (called the basil forebrain) and within the brain stem are
particularly important in regulating our falling asleep
A different brain stem area- where the reticular formation passes through the pons- plays a key
role in initiating REM sleep. This region contains REM sleep on neurons that periodically activate
other brain systems each of which controls a different aspect of REM sleep such as eye
movements, muscular paralysis and genital arousal
Why Do We Sleep?
According to the restoration model- sleep recharges our rundown bodies and allows us to recover
from physical and mental fatigue
Some researchers believe that a cellular waste product called adenosine plays a role in getting are
bodies to restore
Adosenine is produced as cells consume fuel. As adosenine accumulates it influences brain
systems that decrease alertness and promote sleep, signaling the body to slow down because too
much cellular fuel has been burned
Evolutionary/ Circadian sleep models- emphasize that sleep’s main purpose is to increase a
species’ chances of survival in relation to its environmental demands.
REM Rebound effect- a tendency to increase the amount of REM sleep after being deprived of it
Insomnia
Insomnia- refers to chronic difficulty in falling asleep, staying asleep or experiencing restful sleep
Pseudominsomniacs- complain of insomnia but sleep normally when examined
Stimulus Control= is based on learning principles. It involves conditioning your body to associate
the stimuli in your sleep environment with sleep rather than with waking activities and
sleeplessness.
Narcolepsy
Narcolepsy= extreme daytime sleepiness and sudden uncontrollable sleep attacks that may last
from less than a minute to an hour. No matter how much narcoleptics rest at night, sleep attacks
may occur at any time. When a sleep attack occurs, narcoleptics may go right into a REM stage
and some of these REM stages have intense dreamlike visual images and sounds
Cataplexy= abnormal version of the normal muscular paralysis that takes place during nighttime
REM sleep.
Many experts view narcolepsy as a disorder in which REM sleep intrudes into waking
consciousness
REM Sleep Behavior Disorder