After reading this chapter, you should be able to
- describe the early theories of memory proposed by the Associationists and the early memory studies of Hermann Ebbinghaus
- explain the behavioral and cognitive approaches to studying learning and how they differ
- explain the advantages and disadvantages of using animals in psychological research
- discuss intervening variables and the debate over whether they should be used in psychology
- explain how our sensory receptors respond to “simple sensations” and how feature detectors in the visual system respond to more complex patterns
- list three main types of changes that can take place in the brain as a result of a learning experience, and present evidence for each type
If you know nothing about the branch of psychology called learning
, you may have some misconceptions about the scope of this field. I can recall browsing through the course catalog as a college freshman and coming across a course offered by the Department of Psychology with the succinct title “Learning.” Without bothering to read the course description, I wondered about the contents of this course. Learning, I reasoned, is primarily the occupation of students. Would this course teach students better study habits, better reading, and better note-taking skills? Or did the course examine learning in children, covering such topics as the best ways to teach a child to read, to write, to do arithmetic? Did it deal with children
who have learning disabilities? It was difficult to imagine spending an entire semester on these topics, which sounded fairly narrow and specialized for an introductory-level course.
My conception of the psychology of learning was wrong in several respects. First, a psychology course emphasizing learning in the classroom would probably have a title such as “Educational Psychology” rather than “Learning.” My second error was the assumption that the psychology of learning is a narrow field. A moment’s reflection reveals that students do not have a monopoly on learning. Children learn a great deal before ever entering a classroom, and adults must continue to adapt to an ever-changing environment. Because learning occurs at all ages, the psychological discipline of learning places no special emphasis on classroom learning. Furthermore, since the human being is only one of thousands of species on this planet that have the capacity to learn, the psychological discipline of learning is by no means restricted to the study of human beings. For reasons to be explained, a large percentage of all psychological experiments on learning have used nonhuman subjects. Though they may have their faults, psychologists in the field of learning are not chauvinistic about the human species.
Although even specialists have difficulty defining the term learning precisely, most would agree that it is a process of change that occurs as a result of an individual’s experience. Psychologists who study learning are interested in this process wherever it occurs—in adults, school children, other mammals, reptiles, and even insects. This may sound like a large subject, but the field of learning is even broader than this because psychologists study not only the process of learning but also the product of learning—the long-term changes in one’s behavior that result from a learning experience.
An example may help to clarify the distinction between process and product. Suppose you glance out the window and see a raccoon near some garbage cans in the backyard. As you watch, the raccoon gradually manages to knock over a garbage can, remove the lid, and tear open the garbage bag inside. If we wanted to study this raccoon’s behavior, many different questions would probably come to mind. Some questions might deal with the learning process itself: Did the animal open the can purely by accident, or was it guided by some “plan of action”? What factors determine how long the raccoon will persist in manipulating the garbage can if it is not immediately successful in obtaining something to eat? These questions deal with what might be called the acquisition phase, or the period in which the animal is acquiring a new skill.
Once the raccoon has become skillful at opening garbage cans, we can ask questions about its long-term performance. How frequently will the raccoon visit a given backyard, and how will the animal’s success or failure affect the frequency of its visits? Will its visits occur at the most advantageous times of the day or week? Such questions concern the end product of the learning process, the raccoon’s new behavior patterns. This text is entitled Learning and Behavior, rather than simply Learning, to reflect the fact that the psychology of learning encompasses both the acquisition process and the long-term behavior that results.
Because the psychology of learning deals with all types of learning and learned behaviors in all types of creatures, its scope is broad indeed. Think, for a moment, of the different behaviors you performed in the first hour or two after rising this morning. How many of
those behaviors would not have been possible without prior learning? In most cases, the decision is easy to make. Getting dressed, washing your face, making your bed, and going to the dining room for breakfast are all examples of behaviors that depend mostly or entirely on previous learning experiences. The behavior of eating breakfast depends on several different types of learning, including the selection of appropriate types and quantities of food, the proper use of utensils, and the development of coordinated hand, eye, and mouth movements. It is hard to think of human behaviors that do not depend on prior learning.
Considering all of the behaviors of humans and other creatures that involve learning, the scope of this branch of psychology may seem hopelessly broad. How can any single discipline hope to make any useful statements about all these different instances of learning? It would make no sense to study, one by one, every different example of learning that a person might come across, and this is not the approach of most researchers who study learning. Instead, their strategy has been to select a relatively small number of learning situations, study them in detail, and then try to generalize from these situations to other instances of learning. Therefore, the goal of much of the research on learning has been to develop general principles that are applicable across a wide range of species and learning situations.
An experimental chamber in which a rat can receive food pellets by pressing a lever.
B. F. Skinner, one of the most influential figures in the history of psychology, made his belief in this strategy explicit in his first major work, The Behavior of Organisms
(1938). In his initial studies, Skinner chose white rats as subjects and lever pressing as a response. An individual rat would be placed in a small experimental chamber containing little more than a lever and a tray into which food was occasionally presented after the rat pressed the lever. A modern version of such a chamber is shown in Figure 1.1
. In studying the behavior of
rats in such a sparse environment, Skinner felt that he could discover principles that govern the behavior of many animals, including human beings, in the more complex environments found outside the psychological laboratory. The work of Skinner and his students will be examined in depth beginning in Chapter 5
, so you will have the opportunity to decide for yourself whether Skinner’s strategy has proven to be successful.
Attempts to discover principles or laws with wide applicability are a part of most scientific endeavors. For example, a general principle in physics is the law of gravity, which predicts, among other things, the distance a freely falling object will drop in a given period of time. If an object starts from a stationary position and falls for t seconds, the equation d = 16t2 predicts the distance (in feet) that the object will fall. The law of gravity is certainly a general principle because in theory it applies to any falling object, whether a rock, a baseball, or a skydiver. Nevertheless, the law of gravity has its limitations. As with most scientific principles, it is applicable only when certain criteria are met. Two restrictions on the equation are that it applies (1) only to objects close to the earth’s surface and (2) only as long as no other force, such as air resistance, plays a role. Therefore, the law of gravity can be more accurately studied in the laboratory, where the role of air resistance can be minimized through the use of a vacuum chamber. For similar reasons, principles of learning and behavior are often best studied in a laboratory environment. Every chapter in this book will introduce several new principles of learning and behavior, nearly all of which have been investigated in laboratory settings. To demonstrate that these principles have applicability to more natural settings, each chapter will also describe real-world situations in which these principles play an important role.
Within the field of psychology, researchers have studied the topic of learning in several different ways. The remainder of this chapter gives an overview of these different approaches, plus a brief history of the field and some background information that will help you to understand the topics covered in later chapters. We will begin with some of the earliest recorded thoughts about learning and memory, and then we will examine and compare two modern approaches to learning—the behavioral and cognitive approaches. Finally, this chapter will introduce a third approach to studying learning—the neuroscience approach—which examines what happens in the brain and in individual nerve cells when we learn.
The Greek philosopher Aristotle (c. 350 B.C.) is generally acknowledged to be the first Associationist
. He proposed three principles of association that can be viewed as an elementary theory of memory. Aristotle suggested that these principles describe how one thought leads to another. Before reading about Aristotle’s principles, you can try something Aristotle never did: You can conduct a simple experiment to test these principles. Before reading further, take a few moments to try the demonstration in Box 1.1
Aristotle’s first principle of association was contiguity
: The more closely together (contiguous) in space or time two items occur, the more likely will the thought of one item lead to the thought of the other. For example, the response chair
to the word table
illustrates association by spatial contiguity since the two items are often found close together. The
to the word thunder
is an example of association by temporal contiguity. Other examples of association by contiguity are bread-butter
This exercise, which should take only a minute or two, can be called a study of free association. Take a piece of paper and a pencil, and write numbers 1 through 12 in a column down the left side of the paper. Below is a list of words also numbered 1 through 12. Reading one word at a time, write down the first one or two words that come to mind.
Once you have your list of responses to the 12 words, look over your answers and try to develop some rules that describe how you came up with your responses. Can you guess any of Aristotle’s three principles?
Aristotle’s other two principles of association were similarity and contrast. He stated that the thought of one concept often leads to the thought of similar concepts. Examples of association by similarity are apple-orange or blue-green. By the principle of contrast, Aristotle meant that an item often leads to the...