Langston, Cognitive Psychology, Notes 1 -- Introduction/History
I.  Goals.
A.  What is cognitive psychology?
B.  The information processing paradigm.
C.  Classic cognitive psychology architecture.
II.  What is cognitive psychology?
Text:  "Cognitive Psychology refers to all processes by which sensory input is transformed, reduced, elaborated, stored, recovered, and used." Alternatively, "The experimental study of human information processing in its many manifestations."
Experimental study:  Based on the experimental method, empirical, scientific.
Human information processing:  People sometimes operate as information processors.
Many manifestations:  Information comes from the environment, is stored briefly, some is selected for additional processing, something is done to it, it may result in some additional behavior. That's the "transformed, reduced, elaborated, stored, recovered, and used" part.
Some examples of questions of interest:
What is the capacity of short-term memory?
How is short-term memory searched?
How long can memories last?
How do people understand language?
What is attention?
Cognitive psychology covers everything that happens between the presentation of a stimulus and making a response to it.
III.  The information processing paradigm.  (A lot of this was derived from Lachman, Lachman, and Butterfield, 1979.  If you're interested in Cognitive Psychology, this is the best introduction to the paradigm there is.)
A.  From the philosophy of science we get the concept of a paradigm.  It's the overarching world view shared by a group of researchers.  A paradigm has six major parts:
1.  Intellectual antecedents:  The areas of science that have come before and form the foundation.
2.  Pretheoretical ideas:  Assumptions and beliefs underlying a theory.
3.  Subject matter:  What we study (the choice here will determine the nature of the science).
4.  Analogies:  Analogies borrowed from more well-understood systems.  These can have a large influence on the questions asked.
5.  Concepts and language:  How we talk about the science (reflects pretheoretical ideas).
6.  Methodology:  How we do our work.
Cognitive psychology operates under the information processing paradigm.  Let's go over it in detail.  The point here is that if you don't know where you come from, you won't know where you're going.
B.  Intellectual antecedents.  Why are these important to the paradigm?  Because a lot of the new paradigm is designed as a response to inadequacies in the old paradigm.  If you don't know where you come from, it's hard to appreciate why you're doing what you're doing.  A bunch to consider.
1.  Experimental roots:
a.  Structuralists:  Wundt (the first psychological laboratory was established by Wundt in 1879).  Experience is important, but what is it (what is the structure of experience, and how are the pieces combined)?  The technique was to have a trained observer introspect about experience to uncover the structure.  This had its problems, primarily:
1)  Arbitrary:  There's no systematic way to get at the structure.
2)  Introspecting changes what you're introspecting about.
b.  Behaviorists (neobehaviorists):  Watson, Pavlov, Skinner.  American response to structuralism, especially introspection.  What goes on in the head isn't observable, if we want to progress in understanding, we must focus only on observables (behavior).  The radical version of this doesn't sound very psychological today.  For example, if I don't get any water for three days, I'm likely to drink a lot when I get my chance.  You might be tempted to say I was "thirsty."  A behaviorist would not agree.  For them, a mental construct, like thirst, is unnecessary to understand the situation.  A simple model,
Longer without water -> More organism drinks
is sufficient.  We don't need mediating concepts,
Longer without water -> More thirst -> More organism drinks.
This attitude developed from a belief in logical positivism.  This was a set of rules that determined which questions were capable of being answered with empirical means (a.k.a. scientific) and which weren't (a.k.a. unscientific).  Questions about mind, thinking, consciousness, etc. were unscientific, and couldn't be answered.  So, these areas were neglected.  Part of the development of cognitive psychology was a reaction to this attitude.  What makes people interesting to study was explicitly ruled out by logical positivism.
They had two approaches.  Loosely speaking, classical conditioning is the development of associations between novel stimuli and biologically relevant events.  Operant conditioning is the development of associations between stimuli and responses.  This S-R psychology was the big player before the cognitive revolution.
While we explicitly allow mental representation in cognitive psychology, some of the behaviorist program has been retained.  Two examples:
1)  Empiricism.  We still focus on observables, most of what we can observe is behavior.  But, we use those observations to infer something about what's going on mentally.  Most of our observation takes place in controlled, laboratory settings.  We'll see an example of that in a moment.
2)  Nomothetic explanation.  Instead of understanding individuals, we're interested in general rules that would apply to anyone (as opposed to ideographic explanation).
Some other areas of explicit disagreement:
1)  Not totally committed to learning.  We'll pay attention to potentially innate contributions to behavior if there appears to be evidence for them.
2)  Totally committed to humans.  There may be similarities in the ways human and animal nervous systems work, and there may be similarities in learning.  But, we're only interested in humans.  That's who we study.
A related research area was verbal learning.  The materials were sort of verbal (mostly nonsense syllables), and the participants were humans, but verbal learning was more behaviorist than information processing.  Their focus was on how associations were formed and what factors influenced the formation of associations.  the same concepts (like mind) that were taboo for neobehaviorists were also taboo for most verbal learners.  The information processing paradigm did borrow some things from the verbal learners:
1)  Focus on memory
2)  Laboratory procedures (we'll see some of this in the methodology section).
2.  Human engineering:  This was primarily motivated by World War II.  Why do people make mistakes (like shooting friendly forces)?  Incorporating the human element into the design of machines caused humans to be viewed as processors of information.  This leads to the question:  How do people process information?  That takes us to the kinds of questions cognitive psychologists ask.
3.  Information processing roots:  Communication theory has to do with transmitting a signal (information) along a channel to a receiver.  This notion inspired early cognitive psychologists, who regarded humans as information processors.  Information is transmitted along a channel, received, and processed.  The processing results in behavior.  In other words, the mental state dictates behavior, not the physical event.
a.  Mental chronometry:  Donders, Sternberg.  Mental events take time.  We can estimate how much time each activity takes through the use of clever tasks.  Once we know this, we can see what happens to information inside.  Donders’ techniques were problematic.  Sternberg's updating of this technique in the 60’s was a major step for the field.
b.  Information:  Shannon.  Shannon et al. figured out how to quantify information.  His work inspired psychologists to investigate the effect of information on behavior.  For example, the more information a stimulus conveys, the harder it is to detect the stimulus in a noisy environment.
4.  Linguistic roots:  Chomsky.  Chomsky pointed out in 1959 that behaviorist accounts of language could never work.  Some of his arguments had to do with whether or not language rules could be learned.  Chomsky's conclusions were that:
a.  Some aspects of language are innate (the basic grammar).
b.  Language is rule-governed.
c.  Language rules are stored in the head and are used to produce and understand.
Note how these ideas are outside the realm of behaviorist thinking.  These points aren't universally accepted, but early cognitive psychologists were interested in the representation of language.
5.  Synthesis:  Cognitive psychology took:
a.  Focus on observable behavior, but behavior can reflect mental events.
b.  The notion of information.
c.  The idea of internally represented rules.
The result is an experimental science of mental life.  As long as the questions are framed correctly, and observations are properly made, we can understand what happens in people's minds.
C.  Pretheoretical ideas.
1.  Symbol manipulation:  Humans encode, compare, store, etc.  What they use for this are symbols.  Thinking is the manipulation of symbols.
2.  Representation:  Some aspects of the world are represented in the mind.  This representation may be analogical (what's in the head resembles what's being represented).  The representation is symbolic (made of stuff that stands for other stuff).  This is contrasted with direct perception where no intermediate representation is required (Gibson).
3.  Some things may be innate.  They interact with learned stuff to produce cognition.
4.  Cognitive processing takes time, and we can measure that time and use those measurements to understand subparts of the mind.
D.  Subject matter.  Overall, mental processes.  Broken down, we get attention, perception, problem solving, learning, memory, language, knowledge representation, meaning, and comprehension.  Note similarities between this list and the table of contents for the book.
E.  Analogies.
1.  People are information processing devices.  You'll see a lot of words like input and output that might also be used to describe machines.  However, the idea that people are an information processing channel with limited capacity is losing force because it's not very productive.
2.  The computer metaphor.  Minds work like computers.  This is more popular, but it may be losing some ground (possibly to a brain analogy, but that's iffy).
F.  Concepts and language.  It reflects what we've looked at so far.
G.  Methodology.  Borrow an analogy from the biology of the cell.  We're spies looking at a factory.  We see trucks with supplies come in one end, and other trucks come and pick up the finished product.  We have to figure out what goes on in the factory.  The only tool we have is to occasionally send in a shipment of supplies and see what comes out.  We can't go in the factory ourselves.  The mind is like the factory for us.  We want to know about the mental stuff, but can't go in and see it.  We can see what goes in and what comes out, and sometimes we can put stuff in.  Keep in mind that everything mental is going to be inferred.  We say "If it took this long to do task X, then Y and Z (mental processes) must have intervened.  A lot of our methodology is about making safe inferences.
1.  Convergent techniques.  We have some process we think exists.  We attack with several types of investigation coming from different directions, and we see if we get similar results.  A classic example of this is 7±2.  This is the capacity of short-term memory.  It kept showing up in a variety of situations, and eventually George Miller realized it was a fundamental capacity.  Along with convergent techniques, there is also a lot of strong inference.  This involves listing several possible explanations for a phenomenon, then conducting experiments to rule out all but one.  By doing this, we are able to eliminate incorrect theories.
2.  Computer simulation.  One problem with inferring processes is that you can infer anything.  We can't take brains apart and put them together again to check if we're right.  Instead, we make computer simulations that have just the parts we claim operate, and then manipulate those to see if they do what people do.  If the simulations work, it's more evidence that we've identified the right processes.  Note, we could still be wrong.
3.  Reaction time.  This is our favorite technique.  Many experiments are based on timing people doing various tasks and inferring processes based on the differences in time.  The Stroop task is an example.

Demonstration:  Color Stroop task and how we can infer mental activities.

Here are some other examples of reaction time being used to make inferences about behavior.
a.  A task:  Inferences when reading.  Do you automatically think of all of the inferences when you read a sentence?  Try this sentence:
"John pounded in the nail"
You might make something called an instrument inference, which is inferring the instrument used to do the action.  In this case, that would be a hammer.  How could we tell if you made this inference?
1)  Naming:
Description:  I present you with a stimulus, usually a word, and you simply name it (out loud) as fast as you can.  So, if I show you the word "phone" you say "phone."
Example:  You read "John pounded in the nail" and then name either "hammer" (related to the sentence) or "knife" (unrelated).  If hammer is part of your representation (you formed the inference), then you should name hammer faster than knife.
2)  Lexical decision:
Description:  I present you with a string of letters ("kpaln" vs. "plank") and you tell me if that string is a word.
Example:  You read our sentence and I show you "hammer" or "knife".  If you formed the inference, then you should say hammer is a word faster than you say knife is a word.  (The answer is "yes" in both cases, knife is just less likely for pounding nails.)
3)  Item recognition:
Description:  You read a segment of text, and at some point (during or after) I present an item (a word or a phrase) and ask you if it came from that text.
Example:  You read "John pounded in the nail" and I ask if "hammer" was in the text.  If you drew the inference, then it should be harder to say "no" to hammer (and it should take longer) than it would be to say no to "knife."
There are more, but that gets the idea across.
IV.  Classic cognitive psychology architecture.  Now, you know something about the background of cognitive psychology.  How do we put that stuff to work?  First, we need an outline of what the mind might look like.  Note, this is just an outline.  We'll end up with something different.
You have three main sets of activities:  Stuff comes in, something happens to it, and stuff goes out.  Here's a rendition of that.
A.  Getting stuff in:  The basic process is to convert from a physical stimulus to mental energy.  Based on work in neuroscience, most people think this part is wired into the brain (sensation).  After that, a lot of complex cognitive stuff happens (perception).  It looks like every aspect of a visual scene is broken down into its elements by the time it reaches the higher cortex.  So, the problem is how it gets put back together.  One of the biggest concerns here has to do with how much "thinking" can influence perception.
Note that there is filtering, not everything gets in.  After that, there is selection.  Some stuff gets more attention than other stuff.
B.  The middle (something happens to it):  For classic cognitive psychology, there are only two things to study:  Representation and process.  Representation is concerned with what is stored and how it is stored.  Process is concerned with what you do with that stuff.  Our goal for this lecture is to determine what would be required for the human cognitive architecture.  I'll maintain two lists, one for representation and one for process.
1.  Representation:
a.  The mind is a physical symbol system.  Physical:  Instantiated in a physical thing (brain) as opposed to floating in the ether.  Symbol:  What it stores are discrete symbols that each stand for (represent) some entity (usually in the world, but possibly something that can only exist in your mind).  Each symbol is stored in a particular location.  This buys into the computer metaphor where computers manipulate symbolic information that's stored at particular addresses in memory.
b.  There's some medium for storage (which we won't attempt to specify for now).  Whatever this medium is, it stores both the facts and operations that you can perform on these facts.  In other words, whatever representational stuff is combined to make a symbol will also combine into a representation of a rule.
Note:  a and b, and some of the others below, take place in the box labeled long-term memory in the picture.
c.  The language of thought is propositions.  Your intuition might be that you think in words, but it should be pretty easy to demonstrate that that isn't true.  Propositions are abstract entities that encode single ideas.  These can be arranged into networks that capture the relationships between ideas.
Demonstration:  Tip of the tongue task.
d.  Your cognitive architecture needs some way to represent mental images.  You can give yourself the phenomenological experience of an image if you try to answer the question "How many windows are there in the house in which you grew up?"  You'll probably imagine yourself walking through the house.  But, is this an actual image like real vision, or is it just a byproduct of thinking in propositions?  For now, we'll admit an image storage and viewing area to our architecture.
e.  Your architecture stores processes.  In particular, rules for performing automatic processes will be stored.  An automatic process has three basic properties:
1)  It can be done in the absence of focused attention.
2)  You usually can't verbalize how you're doing it.
3)  You usually can't stop it once you start it, or prevent yourself from starting it when the situation in which you need it arises.
Processes start out as controlled processes (the opposite of automatic), but with repeated practice they become automated.  We'll think of them as compiled computer programs, and store them in the architecture.
f.  The architecture has a working memory.  It's a place for processing information.  It's in representation because it's a representational medium.  The rest of the architecture is a potential information storage, meaning that you could get at it if you wanted it, but it isn't presently doing anything.  Working memory is the active part of that.  It's useful to have a limit on what you can think about simultaneously to prevent information overload during processing.  If you carefully considered every possibility you could think of before acting, or brought together everything you know about a topic before deciding about it, you'd spend most of your life in a catatonic, immobile state.  This working memory is the short-term memory box in the picture.
2.  Processes:
a.  Some way to satisfy goals.  We would like a general process to solve any problem with which the organism is faced.  This is means-ends analysis.  Basically, you put some end (goal) into a register, and then retrieve the means required to achieve that goal.  You can nest means and ends as deeply as required to get to a solution.  For example, here's something that happened recently:  I want a sandwich for lunch, but have no mustard.  I go to the store and get some.  I realize I have nothing but water to drink.  I put down the mustard and return to the store to buy some Pepsi.  I come home and the dog has stashed the mustard somewhere (apparently thinking it's a toy).  I search for the mustard.  I don't find it.  I use mayonnaise instead.  The main goal is to have a sandwich, but en route to achieving it, a succession of subgoals had to be solved.  Goals can come from three sources:
1)  Memory (as in you remember you were supposed to read for class).
2)  Cognition (as in mustard is required to kill the meaty taste of luncheon meat).
3)  The environment (as in the mustard has been hidden by the dog).
Means can also come from these sources.  For example, if I have a goal to reach something high, the presence of a chair in the immediate environment might provide a means of achieving that goal.  This highlights the value of working memory.  With all of the stuff coming in, you need a limit to keep you on the main path.  Otherwise, all of the possibilities would overwhelm action.
b.  Some image manipulation processes.  There's evidence that you can scan and manipulate mental images.  So, we'll have some processes for it.
c.  A way to automate control processes and a way to execute processes.  Someone has to do the actual work.
d.  Some interpretation processes.  All of that information is useless without some way to make sense of it.
e.  Attention.  This is like the processes’ working memory.  It's a limit on the amount of information that you can process at one time.

Cognitive Psychology Notes 1
Will Langston

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