Download File

Document related concepts

Self-referential encoding wikipedia , lookup

Attitude change wikipedia , lookup

Memory conformity wikipedia , lookup

Transcript



Schemas are cognitive structures (mental
templates or frames) that represent a person’s
knowledge about objects, people or situations.
The concept of schema was first used by Jean
Piaget in 1926 and later developed by Frederic
Bartlett (1932).
Schemas are used to organize our knowledge,
to assist recall, to guide our behavior, to predict
likely happenings, and to help us make sense of
current experiences. They simplify reality.


They come from prior experience and
knowledge. They allows us to take short-cuts in
interpreting vast amounts of Information.
For example, we may have “schemas” for a
good teacher and bad teacher. When we see
behavior similar to our schema of a good
teacher we may then label the teacher as a
good teacher.



Experience can also change schemas.
For example, when you were younger, you may
have thought that a “good teacher” was
someone who gave little to no work and had a
relatively “easy” class.
Your schema for a “good teacher” may now
be someone who prepares you for college and
or helps you to understand the material.



As previously stated, humans integrate new
information with existing, stored information.
Schema theory therefore states that what we
already know will influence the outcome of
information processing. In other words new
information is processed in the light of existing
schema.
Thus, schemas then can affect our cognitive
processes.


While the use of schema theory to learn in most
situations occurs automatically or with little
effort, sometimes an existing schema can
actually hinder the learning of new information.
Prejudice is one example of schema that
prevents people from seeing the world as it
really is and inhibits them from taking in new
information. By holding certain beliefs about a
particular group of people, this existing schema
may cause people to interpret situations
incorrectly. How can a prejudice cause a
misinterpretation of things we view in the world?

When an event happens that challenges these
existing beliefs, people may come up with
alternative explanations that uphold and
support their existing schema instead of
adapting or changing their beliefs.



If you have already stored schema that urban
teenage males are aggressive and you meet a
pleasant urban male teen, your memory of him
may be affected.
If you were surprised with his politeness, you may
remember him as even more polite than he is.
Or, you may not even notice how polite he was
because you were expecting him to be rude,
and so you remember him as the typical urban
teen you had previously imagined in your mind.



Support for the influence of schemas on
cognitive processes is widespread. Bartlett (1932)
demonstrated how schema, specifically cultural
schema, can influence memory in his classic
study.
He gave participants a complex and unusual
story called ‘The War of the Ghosts' which
contained unfamiliar supernatural concepts and
an odd, causal structure to Western participants.
He purposefully did this so the information would
not fit into their preexisting schemas.



He asked them to recall it six or seven times over
various retention intervals.
He found that recalled stories were distorted
and altered in various ways making it more
conventional and acceptable to their own
cultural perspective.
He used the term rationalization to refer to this
type of error - rationalizing it according to what
fitted with their existing cultural schemas - for
example canoe was often substituted for 'boat'.


There is a lot of research to support the idea that
schemas affect cognitive processes such as
memory (Barlett, Loftus, etc.). This theory seems
quite useful for understanding how people
categorize information, interpret stories and make
inferences.
Schema theory has also contributed to our
understanding how cognition develops in children
(Piaget) and also how memories can become
distorted. Furthermore, social psychologists often
refer to 'social schemas when they are trying to
explain stereotyping and prejudice.

Schema theory helps to understand cultural
and gender differences, since different genders
& cultures may have different schemas which
influence the way they interpret the world.

However, there are some methodological flaws
with the research, for example, Bartletts' choice
of material meant that the stories he chose may
not have been meaningful to other people, but
he had no objective measure of
'meaningfulness'.


It is an important to note that much of the
research can be criticized for having low
ecological validity.
Cohen (1993) states that schema theory is
rather vague and the theory fails to offer
detailed explanations of how the schemas are
acquired in the first place. Cohen believes the
theory is overly simplistic (reductionist) and does
not account for complexity of human cognition.

However, recent biological research by
Caramazza (2009) found that from the visual
cortex, information about living and non-living
objects are shuttled to different parts of the
brain as to trigger appropriate reactions—even
in blind participants—so some schemas appear
to be connected to localized areas of the
brain.
Bibliography:
 Bartlett, F.C. (1932). Remembering: A Study in
Experimental and Social Psychology.
Cambridge University Press.
 Fanz, R. L. (1961). Maturation of Pattern Vision in
Infants During First 6 Months. Scientific
American, 204: 66
 Piaget, J. (1926). The Child's Conception of the
World. Towota, NJ. Littlefield Adams.
According to the second principle of the cognitive level
of analysis:
 Models of mental processes can be proposed and
investigated scientifically
Research have looked at models for various cognitive
processes:

Decision Making (availability heuristics, representative
heuristics, etc.)

Language (rote-memory model, abilities model,
critical age model)

Learning (social-learning, classical conditioning, etc.)



Mental models have been studied by cognitive
scientists as part of efforts to understand how humans
know, perceive, make decisions, and construct
behavior in a variety of environments.
The term “mental model” has been used in many
contexts and for many purposes. It was first mentioned
by Craik in his 1943 book, The Nature of Explanation.
(Craik, 1943).
These mental models help us to investigate cognitive
processes scientifically in order understand how these
processes interact, operate, and change with
biological and sociocultural factors.


While several different models of memory have
been proposed, the multi-store memory model
of memory is often used to explain the basic
structure and function of memory.
Initially proposed in 1968 by Atkinson and
Shiffrin, this theory outlines three separate
stages of memory: sensory memory, short-term
memory and long-term memory.


This model is based on two fundamental
assumption:
1) memory can be conceived of as a few
discrete "structures";
2) information passes through these structures in
a systematic order. Information is originally
encountered via the sensory system and is
retained for a very short period of time in
sensory memory (sort of like a "buffer").
As soon as we attend to the information it is
transferred to short term memory, which is
working memory, conscious awareness.
The capacity of short term memory is quite small
relative to long term memory, according to this
model.



Sensory Memory
Sensory memory is the earliest stage of
memory.
During this stage, sensory information from the
environment is stored for a very brief period of
time, generally for no longer than a halfsecond for visual information and 3 or 4
seconds for auditory information.
We attend to only certain aspects of this
sensory memory, allowing some of this
information to pass into the next stage - shortterm memory

Most “strangers” that we see on an everyday
basis, according to this model, usually do not
make it past sensory memory unless something
significant is attached to the person.
Jeffrey Beard




Short-term memory, also known as active memory,
is the information we are currently aware of or
thinking about.
In Freudian psychology, this memory would be
referred to as the conscious memory.
Paying attention to sensory memories generates the
information in short-term memory. Most of the
information stored in active memory will be kept for
approximately 20 to 30 seconds.
While many of our short-term memories are quickly
forgotten, attending to this information allows it to
continue on the next stage - long-term memory.



Long-term memory refers to the continuing
storage of information. In Freudian psychology,
long-term memory would be called the
preconscious and unconscious.
This information is largely outside of our
awareness, but can be called into working
memory to be used when needed. Some of this
information is fairly easy to recall, while other
memories are much more difficult to access.
Example: 12358. This number was possibly in your long
term memory until a “cue” called it into your working
memory.


Laid a foundation for advancements in mental
modeling.
The multi store model of memory was one of
the first models of memory to provide a logical
account of the structures and processes that
make up memory.
It has been an influential model and has lead
to the development of other more
sophisticated theories such as the working
memory model.



Has been supported by research.
Multiple research studies support the
assumption of a structural model for memory.
For example, research by Sperling (1960)
showed support for the capacity and duration
of sensory memory being different to that of
short term memory.
The research by Sperling demonstrated that we
can access more than 9 bits of information if
we try and access them quickly enough from
sensory memory but if this is left longer than 1
second this access fades away (as with the
example of the picture of Jeffrey Beard).
Contemporary limitations
 Nowadays most cognitive psychologists argue
that multi store model provides a limited and
simplistic explanation of memory processed.
 For example the levels of processing approach
demonstrates that information is not transferred
to long term memory simply by rehearsal but
involves more sophisticated processing.
 The model also can not explain why we often
clearly remember highly emotional events.
Such as flashbulb memories.


Case studies of brain damaged participants
such as Clive Wearing also show that the Multistore Model is an oversimplification of how
memory actually works.
Clive was similar to H.M. in that he could not
remember new information for more than a
few seconds; however, he could learn new
skills.



This suggests that there is a separate long term
memory for skills (Procedural Memory).
Clive could also remember facts about his life
prior to the illness, but could not remember any
experiences. This meant that he repeatedly
had revelations that he was conscious for the
first time.
This suggests that there are separate long term
memory stores for facts (semantic memory)
and experiences (episodic memory).


Although the model itself makes real world
sense, the research is mostly experimental and
thus lacks ecological validity.
For example, they lack real world relevance in
the way they often use word lists which are not
a valid indication of how we actually learn and
recall things in everyday life.


The levels of processing model of memory
(Craik and Lockhart, 1972) was put forward
partly as a result of the criticism leveled at the
multi-store model.
Instead of concentrating on the
stores/structures involved (i.e. short term, long
term memory), this theory concentrates on the
processes involved in memory.
37




Unlike the multi-store model it is a nonstructured approach.
The basic idea is that memory is really just what
happens as a result of processing information.
Psychologists Craik and Lockhart proposed
that memory is “just a by-product of the depth
of processing of information and there is no
clear distinction between short term memory
and long term memory.”
Depth, in other words, is how we extract
meaning from the stimuli.
38
The greater the processing of information
during learning, the more it will be retained
and remembered.
39
Shallow Processing
The
crucial assumption of this levels of processing theory
is that retention of an item is dependent on the depth or
level of processing carried out the material.
Superficial processing leads only to shallow, temporary
Retention (which explains why we don’t recall physical
details of strangers unless we find significance in the
stranger); deep processing leads to efficient, durable
retention.
40
Shallow Processing
This takes two forms
 1. Structural processing (appearance) which is when
we encode only the physical qualities of
something. E.g. the typeface of a word or how the
letters look.
 2. Phonemic processing – which is when we encode its
sound.
 Shallow processing only involves maintenance
rehearsal (repetition to help us hold something in the
STM) and leads to fairly short-term retention of
information. This is the only type of rehearsal to take
place within the multi-store model.
41
Deep Processing
 3. Semantic processing, which happens when
we encode the meaning of a word and relate
it to similar words with similar meaning.
Deep processing involves elaboration
rehearsal which involves a more meaningful
analysis (e.g. images, thinking, associations
etc.) of information and leads to better recall.
For example, giving words a meaning or linking
them with previous knowledge.
42

This explanation of memory is useful in
everyday life because it highlights the way in
which elaboration, which requires deeper
processing of information, can aid memory.
43



Reworking – putting information in your own
words or talking about it with someone else.
Method of loci – when trying to remember a list
of items, linking each with a familiar place or
route.
Imagery – by creating an image of something
you want to remember, you elaborate on it
and encode it visually (i.e. a mind map).
44



The theory is an improvement on Atkinson &
Shiffrin’s account of transfer from STM to LTM.
The levels of processing model changed the
direction of memory research.
It showed that encoding was not a simple,
straightforward process. This widened the focus
from seeing long-term memory as a simple
storage unit to seeing it as a complex
processing system.
45



Craik and Lockhart's ideas led to hundreds of
experiments, most of which confirmed the
superiority of 'deep' semantic processing for
remembering information.
It explains why we remember some things
much better and for much longer than others.
This explanation of memory is useful in
everyday life because it highlights the way in
which elaboration, which requires deeper
processing of information, can aid memory.
46



Despite these strengths, there are a number of
criticisms of the levels of processing theory:
It does not explain how the deeper processing
results in better memories.
Deeper processing takes more effort than
shallow processing and it could be this, rather
than the depth of processing that makes it
more likely people will remember something.
47

The concept of depth is vague and cannot be
observed. Therefore, it cannot be objectively
measured.
48

What do we already know about the
relationship between physiology and cognition
that can help us to answer this question?
50


This means that anytime you are thinking, the
brain is working.
In other words….everything psychological has
a physiological origin.
With this assumption, damage to the physical
brain , imbalances in neurotransmission and
hormones, genetic mutations, food & drug
intake, sleep deprivation, and other biological
factors can all impact cognitive processes.




Hippocampus damage and amnesia (i.e. Clive
Wearing and deficits in memory).
Low Dopamine Levels and deficits in multiple
cognitive functions.
Sex Hormonal Levels and cognitive decline.
Sleep deprivation negatively impacting our
mood, our ability to focus, and our ability to
access higher-level cognitive functions


The earliest scientific evidence of a link between
sleep and performance dates back to the early
1930’s, when Nathaniel Kleitman, one of most
significant figures in the field of sleep medicine,
discovered a daily pattern in the speed and
accuracy of cognitive performance.
He showed that even in well-rested individuals
there was a decrease in the level of individual
performance that occurred in the early morning
and again late at night.




Thus, even when we are getting the amount of
sleep we need, we can still expect normal
fluctuations in our ability to function.
Many students study “early in the morning” or
“late at night”. From this research, how can this
impact your cognitive performance?
Epinephrine, an excitatory neurotransmitter, is
naturally at lower levels in the morning and late
at night.
Low levels have been can result in lack of focus,
and low levels of motivation. This is why we often
feel less motivated in the morning time.



In addition to these normal fluctuations, not getting
enough sleep—whether for just one night or over the
course of days to weeks—has a significant effects on
our ability to function.
Sleep deprivation negatively impacts our mood, our
ability to focus, and our ability to access higher-level
cognitive functions.
The combination of these factors is what we
generally refer to as cognitive performance. In the
laboratory, researchers use scientific studies to
determine just how significantly varying levels of
sleep disturbance impact various types of cognitive
processes.



In addition to these normal fluctuations, not getting
enough sleep—whether for just one night or over the
course of days to weeks—has a significant effects on
our ability to function.
Sleep deprivation negatively impacts our mood, our
ability to focus, and our ability to access higher-level
cognitive functions.
The combination of these factors is what we
generally refer to as cognitive performance. In the
laboratory, researchers use scientific studies to
determine just how significantly varying levels of
sleep disturbance impact various types of cognitive
processes.


In addition to the feeling of mental fatigue and
changes in brain activity that accompany a
night without sleep, other measures of
performance are noticeably altered.
Concentration, working memory, mathematical
capacity, and logical reasoning are all aspects
of cognitive function compromised by sleep
deprivation.


However, not all of these functions rely on the
same regions of the brain, nor are they
impacted by sleep deprivation to the same
degree.
For example, the region of the brain known as
the prefrontal cortex (PFC) is responsible for
many higher-level cognitive functions and is
particularly vulnerable to a lack of sleep. As a
result, people who are sleep deprived will begin
to show deficits in many tasks that require logical
reasoning or complex thought.


However, not all of these functions rely on the
same regions of the brain, nor are they
impacted by sleep deprivation to the same
degree.
For example, the region of the brain known as
the prefrontal cortex (PFC) is responsible for
many higher-level cognitive functions and is
particularly vulnerable to a lack of sleep. As a
result, people who are sleep deprived will begin
to show deficits in many tasks that require logical
reasoning or complex thought.

Research suggest that a loss of REM, or rapid eye
movement sleep (a period of intense sleep ) can
result in increased irritability (correlated with
lower norepinephrine levels) anxiety and
depression (correlated with lower serotonin
levels), decreased socialization, reduced
concentration and decreased ability to handle
complex tasks (due to low levels of PEA) and to
be creative (due to lower dopamine levels).

Research suggest that a loss of REM, or rapid eye
movement sleep (a period of intense sleep ) can
result in increased irritability (correlated with
lower norepinephrine levels) anxiety and
depression (correlated with lower serotonin
levels), decreased socialization, reduced
concentration and decreased ability to handle
complex tasks (due to low levels of PEA) and to
be creative (due to lower dopamine levels).

Determining just how much performance is
affected by sleep loss is difficult, in part because
of factors such as individual differences in
sensitivity to sleep deprivation, as well as
individual differences in motivation to stay alert
despite sleep loss. Even so, the evidence is clear
that a lack of sleep leads to poor performance.


Research suggests that the nerve connections
that make our memories are strengthened
during sleep. ‘
“Sleep embeds the things that we have learned
and experienced over the course of the day into
our short-term memory,” says Avelino Verceles,
MD, assistant professor at the University of
Maryland School of Medicine and director of the
school’s sleep medicine fellowship.



It appears that different phases of sleep play
different roles in consolidating new information into
memories. If your sleep is cut short or disrupted, it
interferes with these cycles.
When you’re sleepy, you may forget and misplace
things often. The inability to focus and concentrate
caused by sleepiness further weakens memory.
“If you’re not able to concentrate on what’s at
hand, it’s not going to make it into your short-term
memory and then long-term memory,” says Allison T.
Siebern, PhD, a Fellow in the Insomnia and
Behavioral Sleep Medicine Program at the Stanford
University Sleep Medicine Center.