Chapter 4 The Mind and the Conscious.docx

14 views10 pages
18 Apr 2012
School
Department
Course
Professor
Page:
of 10
Chapter 4 The Mind and the Conscious
How is the conscious mind experienced?
How does neural activity give way to subjective experience of the world/
Consciousness refers to the moment-by-moment subjective experiences, like reflecting
on immediate surroundings. Has contents; things we are aware of and levels; coma,
awake, sleepy.
Rene Descartes- dualism: mind physically distinct from brain. Rejected, mind and brain
in unison
Consciousness is a subjective experience
Qualia describes the properties of subjective experiences. Subjective nature masks ability
to definitively state. SEEING RED.
Type of neural activity denotes thought.
Variation in conscious experience
- levels of consciousness vary throught day (ex. Waking up from sleep). Affected
by substances and mind state (relaxed)
Definition by William james: concsciousness is the continuous stream of thoights that
float from one to another.
Features:
- unified coherent experience.
- Limited in we cant pay attention or be aware of everything
- Automoatic atasks are done that require little consciousness
- Controlled processing involves doing difficult taks that require lots of attention.
CONSCIOUSNESS AND CO MA
-in comas there are sleep/wake cycles where eyes appear awake and then close to appear
to be asleep, but there no response to surrounding. When this condition latss for more
than a month, it is called a vegetative state . Longer vegetative state, less the chances of
recovering consciousness or showing normal brain acitivity.
- Minimally conscious state: between full and vegetative state. People may make
deliberate movements, like moving eyes to communicate. Better prognosis. Jan grebski,
a man woke up from a 19 year coma and he remembered events from those 19 years
- while looking at behavior to differentiate between states of consciousness is good,
brain imaging is more useful and can also determine extent of damage and
likelihood of recovery.
- Even in coma, brain activity can be seen through electronic activity.
Example: terri shiavo had legal battle over whether or not to pull plug. She was let go
once an EEG was done ro show no activity.
SPLITTING THE BRAIN SPLITS THE CONSCIOUS MIND
In case of seizures, two sides of bran are disconnected by cutting the corpus calosum in
order to isolate the seizure. This occurs in case medications don’t work. Results in split
brain:
- provides many insights into function and organization of hemispheres
- people very normal after procedures with few exceptions like
a) the mind is split when the brain is split
experiment: Left hemisphere of brain in dominant for language
when someone is asked to pick something up using left hand, right hemisohere is doing
action. Ask the person what there picking up, and they cant tell you because there left
side of the brain does not know wat being picked up as the information is not being
passed from right side of brain to left side. Left brain doesn’t know what right brain has
picked up. If the object however is on the right side of the person, the right eye and hand
will work to pick it up using the left hemisphere, where it will then be able to determine
what it is.
- left brain is hopeless at spatial relationships. Try and have right hand controlled
by left hemisphere arrange blocks and it wont go well
the interpreter:
left hemisphere tries to make sense of actions by right hemisphere.
Man has two images pop up. on left side of screen there snowy house, and on right side
there’s a chickens foot. Below is list of images corresponding to images.
Man uses left hemisphere to have hand touch image of chicken and the right hemisphere
has him touch image of shovel for snowy house. The left hemisphere the talking
hemisphere explains the logical correlation between chicken claw and chicken, and then
when asked why he picked the shovel, the left hemisphere, reasons (without the
information from the right hemisphere) that the shovel is for cleaning up the chickens
coop, and not because chicken claw goes with chicken.
-The left side being so good to construct world is thus called the interpreter
Another quick example, person is told to get up on right side of hemisphere. Once up,
he’s asked why he got up, left brain, speaking side doesn’t know why so story is made up
The interpreter speculates
- interpreter strongly influences the way we view world.
- Distortion of narrative occurs where themes are created to represent
- Left-brain can make life more difficult. Humans don’t follow optimal stratageys
but rather try and look for patterns etc.. why doe we do this? Left brain tells us to
look for patterns. When split brain people were put to task where right brain was
involved, the performed better in red light green light tas
UNCONSCIOUS PROCESSING INFLUENCES BEHAVIOR
central property of conscioussness: we are aware of some mental proceses and not aware
of others. * how do i know my phone number. automatic process
subliminal perception are unconscious cues that affect cognition
evidence shows that subliminal mesaging has little effect on purchasing behavior but it
does have a large effect on how we think
most powerful when the cues work on motivation. flashing money made people work
harder. flashing thirst
- Freudian slip where unconscious thought is expressed.
- Thoughts of old people actually made people walk slower.
The smart unconscious
- literally sleeping on it: it is in some cases better to make a decisions that one for the
most part does not consciously think of, rather than solely thinking of that one thing.
Verbal overshadowing builds on idea of smarter unconscious. People who picked best
jame one by one did well, but when asked to pick jame one by one and break in between
each to explain selection, they did poorly. Verbal overshadowing explains that permance
is impaired by verbal need to explain themselves on topics hard to talk about. Picking
painting! Take home message is that we are bad at describing perceptual experiences, and
that if we do so verbally we alter our memories.
BRAIN ACTIVITY PRODUCES CONSCIOUSNESS (ORGANE)
Studying damage to brain helps identify selective loses in consciousness related to area of
brain.
1. Blindsight:
Condition in which person experiences some blindness due to damage to visual systems
but have some spared visual capacities but is unaware to being able to see at all.
Being aware of surrounding while not being able to see anything. Amygdala also
processes visual information crudely and quickly
Global workspace:
- consciousness arises as a function of which brain circuits are active
ex. Hemineglect
What is sleep
Facts:
a) brain is still active while person is asleep. Many regions are more active than
theyd regularily be( person is better at solving difficult question after sleep).
b) Conscious part of world largely turned off.
c) Sleep amounts differ by individuals
d) Sufficient sleep is important for memeory and health
Sleep is an altered state of consciousness
- brain still processes info and is aware of environment while asleep.
- Brain at work can be seen when people don’t role over onto pets while asleep.
- EEG shows that when people awake, beta waves produced by neurons, and when
asleep or eyes closed, alpha waves made.