Session Three: Learning and Cognition/Cognitive Information Processing/Schema Theory
Instructor notes written by J. David Perry, Ph.D., Indiana University.
Instructor notes: Approaches to the study of learning
Introduction to CIP
Cognitive information processing (CIP) is not associated with the work of a single theorist; rather, it builds on the work of a number of researchers who share a common paradigm. Like the behaviorists, CIP theorists are concerned about observable behaviors; but, unlike behaviorists, they use those behaviors to make inferences about underlying mental processes that cannot be directly observed.
The basic CIP model is concerned with fundamental mental operations, mainly how we perceive and remember events and information. We will cover higher-level skills such as problem-solving and critical thinking in later units.
Three basic components of memory are proposed: the sensory register, short-term or working memory, and long-term memory.
The sensory register
In order for something to get into long-term memory, it must first "register" with us. The meaning we assign to sensory impressions depends on both our background knowledge and the context in which we experience something. As we've all experienced, our attention can be very selective. For example, some years ago I bought a kind of Volkwagen called a Type IV. These were only made for three years in the early '70s, so they were fairly rare. When I bought mine it was about 8 years old. I would have sworn that I had never seen a car like this before. (It looked sort of like a VW
Beetle, only larger.) After I bought my car, I started seeing them all over the place. Well, not really, but I probably saw one at least three or four times a week. Did these cars just suddenly start showing up in Bloomington? I think not. They were there before, but they just didn't register with me. After I owned one, I was sensitized to them.
The role of context is obvious in language perception. For example, the word "tape" can have several meanings. But if I say, "I have to wrap a birthday present--do you know where the tape is?", most people would have no trouble perceiving that I'm looking for the roll of sticky stuff, not a video- or audiocassette. Also, you've probably had the experience of encountering someone who you recognize from one realm of your life (e.g., they work in your building) in another realm (e.g., at your daughter's soccer game). You may realize you know that person, but not be able to figure out why you know them. This is a context issue.
One of the problems that CIP researchers have wrestled with is, how do we recognize things? You should be familiar with the four different theories of pattern recognition discussed in the text.
Short-term memory
After a sensory impression has registered, it then passes into short-term memory, or working memory. The capacity of short-term memory appears to be rather limited. We can hold only about 7 "chunks" of information in short-term memory at a time. Of course, the size of a chunk is relative, not absolute. We might have trouble managing 7 single words in a language that was not known to us, but might easily be able to manage 7 sentences in our own language. The difference is that the unknown words are meaningless to us, whereas the sentences in our own language are meaningful, and therefore don't require as much working capacity.
What happens to information while it is in working memory determines whether--and how--it will get stored in long-term memory. We can hold things in working memory for a while by "rehearsing" them. An example of this is when we repeat a phone number or person's name to ourselves just long enough to dial a number or make an introduction. After we've used the information, it will probably be lost to us.
To get information stored in long-term memory requires that it be "encoded" in some way. Encoding can be accomplished in several ways. "Mnemonics" are memory tricks we can use to remember lists of names, numbers, etc. Many CIP researchers have been fascinated with what mnemonics can tell us about how memory works; however, these strategies are not in great demand in instructional settings today, since we usually don't consider memorization to be a very important learning outcome. In the longer term, the kinds of encoding strategies that work best are those that emphasize meaningfulness. One way to do this, with
text for example, is to make the organizational structure of the material apparent. That's why we use outlines, headings, and other kinds of textual "cues" to indicate major and minor ideas, show relationships among concepts, etc.
Long-term memory
Some important concepts in long-term memory:
Declarative vs. procedural knowledge. Knowing "that" Bill Clinton was elected President of the U.S. is quite different from knowing "how" to conduct a successful presidential campaign. Similarly, memorizing the seven steps in the negotiating process is very different from being able to use those steps to negotiate successfully.
Declarative knowledge can be broken down in to episodic and semantic memory, or memory for events versus memory for verbal information. We have an episodic memory for the automobile accident we were in 13 years ago, but we have only a semantic memory of the "fact" that Columbus landed in the New World in 1492 (unless we were there).
Verbal and imaginal representation in memory. Words that have concrete referents (and therefore can easily be "pictured") are more likely to be remembered than abstract words. So, if I read a list of 30 words and ask you immediately afterwards to write down as many as you can remember, you will probably be more successful with words such as "skyscraper", "baboon", and "rake", than with words such as "strategy", "reference", and "nominal".
Retrieval. The difference between a "recall" task and a "recognition" task is an important one in education. As a student, I always liked multiple choice tests. Why? Because they usually require only recognition of some term or definition, which is much easier cognitively than an essay-type exam, which typically involves free "recall" tasks. However, life rarely presents us with multiple-choice options, so if we want school tasks to resemble life tasks... Well, you get the point.
Encoding specificity. The best retrieval cues are the same as the cues used for encoding. For example, remember the diagram of the theory-building process on page
7 of your text? Suppose I told you to memorize that for an exam. According to the concept of encoding specificity, it would probably be easier for you to reproduce the steps in that chart if I gave you a blank version exactly like the original chart than if I simply told you to list the seven steps. That's because the form of the chart (circular, with arrows) serves as a retrieval cue for the information.
Forgetting. Some theorists contend that we never truly "lose" anything once it is stored in long-term memory (unless the brain is damaged in some way). If that is so, then when we forget something, it must either be the case that it was never actually encoded in the first place, or that the information is still there, but we can no longer retrieve it. So the phone number that we repeated just long enough to dial is forgotten because it never really got into long-term memory. The phone number that my family had when I was a child is probably still stored in my brain, but I can no longer retrieve it. Likely, this number has suffered from retroactive interference, because of all the phone numbers I have had to learn and remember since then. (However, I could probably pick it out of a multiple-choice list!)
Some implications of CIP for instruction
Provide organized instruction. Make the structure and relations of the material evident to learners, such as through concept maps or other graphic representations.
Link new material with what is currently known. This provides a sort of mental "scaffolding" for the new material.
Recognize the limits of attention (sensory register). Help learners focus their attention through techniques such as identifying the most important points to be learned in advance of studying new material.
Recognize the limitations of short-term memory. Use the concept of chunking: don't present 49 separate items, make them 7 groups of 7. Use elaboration and multiple contexts.
Match encoding strategies with the material to be learned. For example, don't encourage the use of mnemonic techniques unless it's really essential to memorize the material. If you want it to be processed more "deeply", then find encoding strategies that are more inherently meaningful.
Provide opportunities for both verbal and imaginal encoding. Even though it's not clear whether these are really two different systems, it does appear that imaging can help us remember.
Arrange for a variety of practice opportunities. The goal is to help the learner generalize the concept, principle, or skill to be learned so that it can be applied outside of the original context in which it was taught.
Help learners become "self-regulated." Assist them in selecting and using appropriate learning strategies such as summarizing and questioning.
Sidebar: Schema theory
Why do we need schema theory?
Suppose you overheard the following conversation between two college-age
apartment-mates:
A: Did you order it?
B: Yeah, it will be here in about 45 minutes.
A: Oh... Well, I've got to leave before then. But save me a couple of slices,
okay? And a beer or two to wash them down with?
Do you know what the roommates are talking about? Chances are, you're pretty
sure they are discussing a pizza they have ordered. But how can you know this?
You've never heard this exact conversation, so you're not recalling it from
memory. And none of the defining qualities of pizza are represented here, except
that it is usually served in slices, which is also true of many other things.
The other theories we discuss in this course would have a difficult time
explaining how we can comprehend this conversation. Schema theory would suggest
that we understand this because we have activated our schema for pizza (or
perhaps our schema for "ordering pizza for delivery") and used that
schema to comprehend this scenario. Schema theory attempts to explain how we
actively make meaning of information.
What is a schema?
A schema (plural schemata) is a hypothetical mental structure for representing
generic concepts stored in memory. It's a sort of framework, or plan, or script.
According to Stein and Trabasso (1982), schemata are thought to have these
features:
- Schemata are composed of generic or abstract knowledge; used to guide
encoding, organization, and retrieval of information.
- Schemata reflect prototypical properties of experiences encountered by an
individual, integrated over many instances.
- A schema may be formed and used without the individual's conscious
awareness.
- Although schemata are assumed to reflect an individual's experience, they
are also assumed to be shared across individuals [in a culture?].
- Once formed, schemata are thought to be relatively stable over time.
- We know more about how schemata are used than we do about how they are
acquired.
Driscoll suggests that a schema is analogous to:
- A play, in that it has a basic script, but each time it's performed, the
details will differ.
- A theory, in that it enables us to make predictions from incomplete
information, by filling in the missing details with "default
values." (Of course, this can be a problem when it causes us to
remember things we never actually saw...)
- A computer program, in that it enables us to actively evaluate and parse
incoming information.
How are schemata created and modified?
Schemata are created through experience with people, objects, and events in
the world. When we encounter something repeatedly, such as a restaurant, we
begin to generalize across our restaurant experiences to develop an abstracted,
generic set of expectations about what we will encounter in a restaurant. This
is useful, because if someone tells you a story about eating in a restaurant,
they don't have to provide all of the details about being seated, giving their
order to the server, leaving a tip at the end, etc., because your schema for the
restaurant experience can fill in these missing details.
Not all of the information we have about restaurants necessarily gets added
to our schema. For example, there's a restaurant in Indianapolis where the
seating booths are little jail cells. After you're seated, the server closes
your cell doors. (Of course, you can escape any time you want, as long as you've
paid your bill.) Even though I've been to this restaurant several times, I don't
think my restaurant schema includes tables as miniature jail cells. This
information is simply an outlier; it is too unlike my experience at other
restaurants.
Three processes are proposed to account for the modification of schemata:
- Accretion: New information is remembered in the context of an
existing schema, without altering that schema. For example, suppose I go to
a bookstore, and everything I experience there is consistent with my
expectations for a bookstore "experience." I can remember the
details of my visit, but since they match my existing schema, they don't
really alter that schema in any significant way.
- Tuning: New information or experience cannot be fully accommodated
under an existing schema, so the schema evolves to become more consistent
with experience. For example, when I first encountered a bookstore with a
coffee bar, I probably had to modify my bookstore schema to accommodate this
experience.
- Restructuring: When new information cannot be accommodated merely
by tuning an existing schema, it results in the creation of new schema. For
example, my experience with World Wide Web-based bookstores may be so
different from my experience with conventional ones that I am forced to
create a new schema.
Why is schema theory important in teaching and learning?
It's important to understand that schemata are powerful forces in learning. In
an article on the role of schemata in story comprehension, Stein and Trabasso
(1982) noted that:
- Schematic knowledge has a significant effect on organization of ambiguous
or disorganized stories.
- Narrative schemata specify expected components of a story, such as the
time sequence of events, and causal relations that should connect the
events; during encoding or retrieval of a story, missing events may be
inferred to fill in omitted information, and events may be reordered to
correspond to a real-time sequence.
- Many studies have shown that the use of schematic knowledge is so powerful
that listeners have little control over the retrieval strategies used during
recall of narrative information; even when listeners are instructed to
reproduce texts verbatim, they cannot do so when the text contains certain
types of omissions or certain sequences of events.
For example, consider the following excerpt from a story:
The girl sat looking at her piggy bank. "Old friend," she thought,
"this hurts me." A tear rolled down her cheek. She hesitated, then
picked up her tap shoe by the toe and raised her arm. Crash! Pieces of Piggo--that
was its name--rained in all directions. She closed her eyes for a moment to
block out the sight. Then she began to do what she had to do.
If you have a well-developed schema for "piggy banks", this story
should be readily comprehensible. You would understand that traditional piggy
banks were usually made of some fragile, brittle material, that they contained a
slot for inserting and saving coins, and that the money could only be removed by
breaking them.
On the other hand, if you have no schema for piggy bank, the story probably
makes little sense.
What are some implications of schema theory for instruction?
- Provide unifying themes for content, since information that lacks a theme
can be difficult to comprehend, or, worse, the learner may
"accrete" the information to the wrong schema.
- Choose texts with "standard" arrangement so that they conform to
student expectations.
- Encourage students to read titles and headings.
- Point out the structure of particular kinds of texts; e.g., what are the
common features of published research articles?
- Ask questions to determine what students' current schemata might be.
- Pay attention to student answers and remarks that may give clues about how
they are organizing information; i.e., what schemata are they using?
Problem solving and
critical thinking
We
often think of problem solving in a narrow way, such as getting the right answer
on a math or physics question. However, when problem solving is defined in a
broader way, much of human behavior can be framed as problem solving. What
clothes should I wear today? What route should I take to work? Where should I
eat lunch? How should I approach this new project or class assignment? How can I
get my daughter to go to bed at 8:30? Each of these fits the general
definition of a problem: a desired state of affairs that differs from the
current state of affairs. (Example: The current state is that it is lunchtime
and I am hungry; the desired state is that in an hour I want to be back at work
having consumed a satisfying, nutritious meal at a reasonable price.)
Note
that we often solve such problems without conscious awareness. Which raises a
question: Could we spend more of our time in ³desired² states if we
approached problems with greater awareness?
Some useful concepts in problem solving
Well-defined
vs. ill-defined problems. Well-defined
problems are the kind we often encounter in math or science classes, as noted
above. There is usually one correct answer and an algorithm, or set of rules,
that virtually guarantees finding the right answer when correctly applied.
Unfortunately, nearly all of the important problems in the world are of the
second kindill-defined. These problems have multiple possible solutions and
instead of a well-defined algorithm for solving them we have, at best, some
heuristics or guidelines that do not guarantee a correct solution.
Functional
fixedness. Our
ability to solve some problems may be limited by our inability to see objects in
a new light or consider solutions that fall outside of a set of unnecessary
constraints we have imposed. For example, if I am fixed on finding a quick,
pleasant route to drive to work each day, I may never consider alternatives such
as taking the bus or working at home.
Identifying
the problem.
This is more than just the first step in the general problem solving model. It
is crucial, because if we cannot identify that a problem exists, then obviously
we cannot solve it. Note that in school learning it is often the teacher or
textbook that identifies problems; the studentıs only task is to solve a
problem once identified. In the real world, though, problems are often not easy
to identify. For example, floods create misery for thousands of people each year
in the U.S. and many other countries. But what, precisely, is the problem? Has
global warming led to changing weather patterns? Do we need more dams, or fewer?
Or do we need laws that prohibit building houses in flood plains? Unless we can
frame such problems appropriately, we have little chance of solving them
satisfactorily. Donald Schon, in his work on reflective practice,
contends that the ability to frame (identify) problems is one of the most
important factors that distinguishes experts from novices.
Domain-specific
knowledge and the problem of transfer.
In addition to their greater ability to identify problems, another important
factor that characterizes the problem-solving ability of experts is the amount
of domain-specific knowledge they can bring to bear on a task. No matter how
much generalized problem-solving ability I have, I am more likely to solve any
particular problem successfully if I have relevant domain-specific knowledge.
For example, if the problem I have set for myself is to buy a new car that meets
my familyıs needs and budget, I am more likely to succeed the more knowledge I
have about vehicle types, makes, reliability ratings, gas mileage, availability
of local service, etc.
Critical thinking
Critical
thinking is more difficult to define than problem solving. It is a broader term,
and it means different things in different disciplines. It may help to think of
it as more process-oriented, while problem solving is goal-oriented. The best
way to understand what is meant by critical thinking is probably to consider the
kinds of abilities that are thought to comprise it: analyzing arguments; using
deductive and inductive reasoning; judging the reasoning of others; making value
judgments; etc.
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Learning to read
and reading to learn
When
you think about the act of reading in light of the basic information processing
model we discussed in the previous unit, it seems like a truly remarkable feat.
For example, each word we read must be attended to and must stay in working
memory long enough for us to comprehend the overall sentence or paragraph.
Otherwise, we would understand individual words, but have no idea of what the
text as a whole meant! There are several aspects of information processing that
likely aid us in this seemingly difficult task:
Propositional
encoding.
Fortunately, when we read it is usually not necessary to remember words and
sentences in their exact written form. It appears that we convert reading
material into sets of propositions that carry the essential meaning while
reducing the burden on our memories. For example, consider this passage:
Josh leaned back and tossed the football in a high, lazy
arc. Maria looked up to see it spiraling toward her and caught it easily in her
outstretched hands.
We
would likely encode such a passage as two simple propositions: Josh threw the
football. Maria caught the football. Or perhaps as just one: Josh threw
the football to Maria.
Chunking.
Beginning
readers are still struggling with the meaning of words and may have difficulty
holding more than a few words at a time in working memory. Experienced readers,
on the other hand, can manage larger chunks, or units of information, and can
likely hold the meaning of several sentences in working memory.
Bottom-up
and top-down processing.
We appear to use both of these processes in reading. We use bottom-up processing
when we read words or sentences and encode them in memory. We use top-down
processing when our initial understanding of a passage activates relevant
schemata which, in turn, shape our expectations of what is to come and aid in
our comprehension of the material.
Automaticity.
As with any cognitive activity, our skill improves when some aspects of the task
become automatic. So, for example, when we can decode the meaning of most words
without conscious effort, more of our time and attention can be directed to
comprehending the overall meaning of what we are reading.
Meaningfulness.
One of the fundamental principles of cognition is that new information is
meaningful to the extent to which it can be related to what we already know. The
same is true for reading. That is why beginning readers, in particular, should
be provided with material that contains mostly familiar settings and concepts.
Metalinguistic
awareness.
Think of this as a subset of metacognition that has particular relevance to
reading. In order to be a successful reader we must be aware of a number of
things that most of us take for granted: That printed words correspond to spoken
language; that sentences generally consist of one or more propositions; that
propositions usually have a subject and a verb, and often an object; etc. Most
children seem to develop sufficient metalinguistic awareness without these
things being taught explicitly.
Some other issues related to reading and cognition:
Definitional
versus contextual word knowledge.
This closely parallels the distinction in concept learning between knowing the
definition of a concept and being able to use it to correctly classify things we
encounter in the world. Merely having the textbook definition of the concept mammal,
for example, does not necessarily mean that we could correctly classify bats and
whales as mammals if we encountered them. Similarly, with word knowledge,
knowing the definition of irascible is not the same as being able to use
it appropriately in speech or writing.
Schema
theory and text comprehension. Schema
theory holds that, when appropriate schemata are activated as we read, they
facilitate comprehension and shape our expectations about what is to come. (Of
course, when inappropriate schemata are activated the likely result will be
confusion rather than comprehension.) This explains why well-written titles and
headings can be useful. Advance organizers might be thought of as a way to
activate an appropriate schema, or even to provide one when none exists in the
learner.
Cognitive
approaches to mathematics and science: Implications for instruction
Build
on studentsı informal knowledge.
As in any domain, new material is learned more meaningfully when it can be
related to what the learner already knows.
Identify
students' current "theories" or algorithms.
Use
student errors as a source of information about their mental models. These
³buggy algorithms² and naïve misconceptions are typically based on
uncontrolled observations and need to be brought to the studentıs awareness
before they can be challenged.
Use
"think aloud" activities,
since these help to uncover current models.
Model
real problem-solving for students.
Students need to see that solving problems is not just a matter of plugging
numbers into an algorithm; rather it is a matter of determining the kind of
problem so that an algorithm can be successfully applied.
Explicitly
teach problem-solving strategies. Donıt
expect that students will acquire appropriate strategies merely by seeing the
teacher use them. Students will need guided, hands-on experience in using these.
Focus
on processes, structures, and decisions, not answers. If
students have a broad, conceptual understanding they will more likely be able to
solve other kinds of problems in the future, not just the limited set they
encounter in school.
Provide
a mix of problem types,
rather than grouping problems of one type; otherwise, students won't develop
skill at determining the problem type and choosing an appropriate solution
strategy.