Cognitive Process
Do all of our cognitive processes withdraw
from the same cognitive bank? How is
it that we are able to drive a car, chew
gum, talk on the phone and listen to
music all at once? Is it possible that
our mental resources are somehow
specialized in such a way so that different
tasked are allocated different
resources at different strengths? Our brain is
unfathomable in it's ability
distribute responsibility to different regions
and the storage of it's memory
will and can never be known. With technology
many questions are being answered
and with regards to divided attention.
Brain imaging techniques such as the PET
scan uses 2-deoxyglucose, which is
injected into the patient's carotid artery.
Because of its similarity to
glucose (brain fuel) it is absorbed by active
energy consuming neurons.
Fortunately this form of glucose derivative does not
become metabolized hence
giving us the researcher the ability to tell where the
activity is located
with a precision of a few millimeters. The PET scan was at
on time the only
tool used to find the location of neurological processes but
now they have
fMRI, which is less time consuming and less messy. With these
imaging tools,
the use of the computerized tachistoscope and the educated
inferences by
highly educated individuals we are getting closer to understanding
the brain
and the complex web of processes present in divided attention. There
are two
theories that try to explain the phenomena of divided attention. The
first
states that all tasks are basically the same in regards to where they
obtain
their resources. The second calls for a more complex task-specific
resource
pool. General resource theory states no matter what the nature of the
tasks
are they all compete for the same limited pool of resources. With this
theory
in mind all we need to be concerned with is the resource demand, the
combined
cost of all the individual tasks at hand. If the combined demand for
the
tasks is greater than the available resources a task will suffer due
to
interference. Task-specific theory states that two tasks will interfere
with
each other only if the two tasks are similar hence pulling from the same
source.
If the tasks are different, using different cognitive abilities
i.e. Spatial vs.
verbal, then divided attention will be easy because the two
processes take place
in different regions of the brain hence pulling from two
resource pools rather
than just one which in turn explains divided attention.
Many studies prove this
to be true and all conclude the degree of
interference depends on the nature of
the tasks being performed. Working
memory has its limitations and divided
attention can only be so "divided".
Cognitive processes take effort
and there is some times a tie up on the
neurological super highway because of
the time required to put forth that
effort. The way our brain deals with these
little tie-ups is a
response-selector. A response-selector can only deal with on
thing at a time,
just like a waiter can only take one person's order at a time.
If two
consecutive tasks require the response-selector one ends up waiting while
the
selector deals with the other task. Most tasks do not require a constant
aid
of the response-selector so you may select and then initiate an action
and the
time you spend carrying out that action frees up the
response-selector to take
on another task, come up with a solution and then
initiate the response for that
task. This process is a cycle where
response-selector bounces from task to task
this is commonly referred to as
time-sharing and is evidence that divided
attention is also task-general. In
everyday life I myself find that I rely on
divided attention a lot. Most of
my divided attention can be explained by
automaticity. For example I work at
Blockbuster Video as my off campus job and I
find the job very easy due to
practice. Most of my shift is spent on auto pilot
which frees up my resources
to be able to make conversation with my fellow
employees but most often with
customers giving them my reviews on movies I have
seen. Performing tasks on
the computer that at one time took total concentration
with practice have
become actions I could do with my eyes closed. I have noticed
although a
problem with divided attention I tried out for a play for the first
time this
semester and I did not realize how difficult it was to do a "cold
read",
reading lines that are unfamiliar and given no instruction on
proper
dictation. I found my self competing for resources when I went up to
read my
lines and found my self not only trying to read what was on the page,
but also
trying to adjust my tone of voice to parallel what was being said
and adjust my
body movements in attempt to look natural. I had a vague idea
of how divided
attention worked but no where close to the understanding I
have now. I feel that
I understand divided attention very well because I
was able to torture my
roommate with a detailed explanation of it three in
the morning enough so he
became interested in what other knowledge I have
obtained from this class. The
Role of Meaning and Memory Connections
Obtaining new knowledge requires learning
and input of new material into long
term memory. For the new information to
become new knowledge one must
understand the information and interrelate it with
past knowledge or weave it
in with other chunks of information to be entered
into the brains storage
unit refereed to as long term memory. An intricate
indexing procedure is
needed in order to retrieve this information for latter
use. According to the
parallel distributed theory of learning an idea is stored
not as one unit but
rather many sub-units all connected due to there related
meaning. Connections
allow one memory to trigger another and through the
spreading activation of
neurons complex webs of understanding are accomplished.
This is very
convenient because if any part of the material is recalled then
that recall
of information connected to it is more easily recalled. We
memorize
information so much more easily if we are able to see the whole
picture and
understand it to the extent that we are able to organize it.
Organizing material
makes learning easier because by understanding something
it reduces the amount
of information to be remembered. That is because we
think of the elements of an
idea as constituents in an interconnected whole.
We then enter the package whole
into memory rather than it's separate
components. By integrating and unifying
the information with past knowledge
it reduces the effort needed to remember
whatever information needs to be
learned. With this knowledge at hand I have
finally answered a question I
have tormented my grade school teachers with;
"why do we have to know this?"
I would have liked an educated answer
back then but unfortunately it was not
offered. I now know that the knowledge I
obtained from grade school set forth
a foundation for my knowledge I obtained in
high school which in turn built a
layer for my understanding of material I am
learning in college. State
Dependent Memory I found this topic of state
dependent memory very
interesting. I did have a vague understanding of state
dependent memory; it
wasn't till I read the detailed description of it in our
book that I really
grasped the idea. I was able to interrelate it possibly with
a psychological
disorder called post-traumatic stress disorder in soldiers and
the problems
with coming back to civilian life. After reading the text I
speculated that
state dependent memory of wartime events could be triggered if a
stimulus was
to be generalized in some fashion to a stimulus present in a war
environment.
My best friend's dad was in Vietnam and suffers from post traumatic
stress
disorder I have spent countless nights drinking with him listening to
his
stories and firing questions. He has told me his war time memories in
such
detail I am going to use them in some shape or fashion to write a book.
He has
told be that when he gets really stressed out he loses awareness and
is in
battle again. I believe that the stress is the connected state
dependent memory.
He is able to relive the horrible torment of war only
in the presents of extreme
stress since those memories were entered into his
long -term memory during that
emotional state. Further evidence of state
dependent memory is how I seem to
recall information so much better and
quicker when I have a cup of coffee. This
is because there is not a night
that goes buy that I don't have a cup of coffee
when I'm studying. The coffee
must effect me on a multitude of levels including
olfactory and taste not to
mention the arousal of mood experienced by the
caffeine. Misleading
Eyewitnesses I found the texts explanation of how
eyewitness testimony could
be tainted with errors very interesting yet at the
same time very disturbing.
I found it interesting how old information could
become entangled with new
information and perceived as the actual event even
though the new information
was obtained later. Both pieces of information were
integrated into a whole.
I also found it interesting how the manipulation of an
adjective could change
ones perception of an event. People draw inferences on a
wide variety of
things and will assume the presence of an object even if it is
not there.
Eyewitness testimony has been the key factor in putting many innocent
men and
women behind bars. Prosecutors know the tricks of the trade and by
choosing
there questions and carefully picking there adjectives they can get
the
eyewitness to make statements that are total lies or exaggerations of the
truth
and in most cases the witness is not aware of the reality of the truth.
Leading
an eyewitness with certain questions consumes a majority of the
opposition's
objections. I also saw a 20/20 episode where a guy when into
room with a bunch
of kids while being observed by researchers in a two way
mirror, he played with
the children read them a story and maybe rough housed
with them a bit. Some of
the children were simply asked what the man did and
they answered accurately to
the actual event the other children were asked
leading questions and asked if
they remembered the man touching them. At what
point did you feel uncomfortable
when he touched you? What did he do that
made you feel uncomfortable? The first
time around most of the kids told the
truth. A week later after being primed
about unacceptable touching the
children came up with some remarkable statements
shocking and unbelievable,
so unbelievable I still suspend the validity of that
particular piece.
Activation Levels and Response threshold The fact that some
neurons are
easier to activate than others interests me but from a biological
standpoint
I am confused. I know that the resting potential of a neuron is -70mv
and
when activated it jumps to +50mv. The firing of neurons in my
understanding
has to do with mainly the charged isotopes sodium and potassium
passing in and
out of "pumps" or channels which then send an weak electric
impulse
down the neurons axon which is covered by the myelin sheath which is
a
phospholipid bi-layer that acts as a semi-conductor hence allowing the
weak
impulse to travel great distances in the neuro-network. I also know that
an
excited neuron decreases its charge quite quickly. What I don't understand
is
how different detectors have different response thresholds. The book
explains
it's self well I just need to some how better parallel this
knowledge with my
biological knowledge therefore giving me a more concrete
understanding. It says
that detectors that have fired recently will have a
higher baseline level. What
time frame are we talking here? How many msec? It
also says detectors that have
fired frequently in the past will gradually
gain a higher and higher baseline
level. Is this because of more dense
connections? The strengthening of
connection? How does this occur? I do
understand their explanation of these
phenomena when it comes to priming, but
in other facets I do not.