CHAPTER 11
LONG TERM MEMORY II: THE NATURE OF KNOWLEDGE
In the previous chapter we discussed how information is Stored in Long Term
Memory. In this chapter we will continue our discussion of Long Term Memory,
this time focusing on the Nature of what is stored there something we generally refer to as Knowledge.
POSSIBLE DICHOTOMIES IN LONG TERM MEMORY
Up to this point, we have talked about long term memory as if it were a single,
homogeneous entity. Many psychologists argue, however, that long term memory
may have two or more relatively distinct subcomponents.
EPISODIC
VERSUS SEMANTIC MEMORY
Tulvin (1983) makes a distinction between the two types of Memory:
episodic memoryIs ones Memory of Personal Life Experiences
semantic memory
Is ones General Knowledge of the World independent
of personal experience
The two forms of memory are different
in numerous ways. For instance, we remember
events we have experienced (episodic) and we also know
things about the world (semantic). We can often recall when a particular
event happened to us (episodic) but usually cannot recall when we acquired specific facts about the world (semantic). Semantic memory is longer lasting than episodic memory. Example:
You remember how to order a chicken
sandwich at McDonald (semantic), but you may not remember the exact order you made last Tuesday at the McDonalds restaurant
(episodic).
You remember that you celebrate Christmas
on Dec 25th (episodic) but you may not remember specific gifts (semantic) you received on a given Christmas.
DECLARATIVE VERSUS PROCEDURAL KNOWLEDGE
Both episodic and semantic memory relate to the nature of How things were or aresomething that many theorists refer to as declarative
knowledge. But we also have something called procedural knowledge: that is, we
know how to do things.
Consequently, a simple way to distinguish between these two terms is;
Declarative. indicates: How things Are
Procedural...indicates: How to Do Things
EXPLICIT VERSUS IMPLICIT MEMORY
Explicit memory is knowledge that we can easily recall and explain in great
detail.
Implicit memory is knowledge that we cannot consciously recall but that nevertheless
influences our behavior (something that you are not totally sure of but you can imply that this might be the case).
HOW INFORMATION IS ENCODED IN LONG TERM MEMORY
Information is encoded in Long Term Memory in three ways. These three ways are
Symbolically
Imagery
Propositions
Lets briefly examine each in more detail.
SYMBOLICALLY
A Symbol is something that represents an object or event, often without bearing
much direct resemblance to that object or event (The U.S. Flag is a symbol representing America). Consequently we encode information Symbolically.
IMAGERY
If you can imagine you mothers face, the smell of roses or the taste of chocolate,
then you are probably using mental Imagery encoding. Although some theorists
argue against the existence of visual imagery, most psychologist believe that it is a distinct form of information storage.
PROPOSITIONS
Learning theorists believe that meanings are stored as Propositions.. that
is, as small bits and pieces of knowledge concerning objects or events.
A proposition is the smallest unit of knowledge that can stand as a separate
statement and can be judged as being true or false. To illustrate, consider the
following sentence:
Marys
Uncle, whom she adores, owns a red Ferrari.
We can break this complex sentence into four smaller assertions, each containing
part of its meaning:
1. Mary has an Uncle
2. Mary adores the Uncle
3. The Uncle owns a Ferrari
4. The Ferrari is red.
So, as you can see, we can store information (knowledge) without remembering
word for word the precise details of an object or event. This process is called
proposition encoding.
PRODUCTIONS
Some knowledge is procedural (how to, or what to do). Some theorists
have suggested that procedural knowledge is encoded in the form of Productions.
For example, productions for riding a bicycle would include IF-THEN rules such
as these:
1 IF
I want to speed up, THEN I must petal faster
2 IF
I want to slow down, THEN I must pedal at a slower rate
3 IF
I want to stop, THEN I must squeeze the brakes
As you can see in this example, in order to do something certain procedures
must be followed. This procedural knowledge is an example of Production encoding.
ORGANIZATION OF LONG TERM MEMORY
Contemporary theorists believe we organize information in long term memory
through a process of association.
To illustrate what I mean, take a piece of paper and try this exercise. Write down the work
BEACH
Now right under beach list a word that comes to mind after beach and do this
for each successive word you list. Now lets share our lists.
Some of your associations might be similar to someone else and others might
be unique to you only.
Psychologists believe that all pieces of information stored in long term memory
is directly or indirectly related to one another. This exercise demonstrates
organization of information in long term memory through association.
LONG TERM MEMORY AS A HIERARCHY
Theorists believe that long term memory is organized hierarchal. General
Super-ordinate information (important) is stored at the top of the hierarchy and Subordinate information below at the bottom
of the hierarchy.
In other words, information is stored in order or most important of relevant
to the least important of perhaps irrelevant information.
GENERALIZATIONS ABOUT THE NATURE OF KNOWLEDGE
In this chapter we have considered several aspects of the knowledge that we
store in long term memory, including the various kinds of knowledge that we are likely to acquire, the variety of ways in
which we might encode it, the possible organizational structures that our long-term memories may have overall and the particular
mechanisms that we might use. At this point, lets make some final generalizations
about the nature of knowledge.
- we often store information in long term memory in more than one way:
- Most of our knowledge is a summary of our experiences rather than information about specific events:
- In most situations integrated knowledge is more useful than fragmented knowledge:
- The in-dept study of a few topics is often more beneficial than the superficial study of many topics:
