Learning and Behavior James E. Mazur Seventh Edition ISBN 10: 1-292-02274-4 ISBN 13: 978-1-292-02274-1 Pearson Education Limited Edinburgh Gate Harlow Essex CM20 2JE England and Associated Companies throughout the world Visit us on the World Wide Web at: www.pearsoned.co.uk © Pearson Education Limited 2014 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without either the prior written permission of the publisher or a licence permitting restricted copying in the United Kingdom issued by the Copyright Licensing Agency Ltd, Saffron House, 6–10 Kirby Street, London EC1N 8TS. All trademarks used herein are the property of their respective owners. The use of any trademark in this text does not vest in the author or publisher any trademark ownership rights in such trademarks, nor does the use of such trademarks imply any affi liation with or endorsement of this book by such owners. ISBN 10: 1-292-02274-4 ISBN 13: 978-1-292-02274-1 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library Printed in the United States of America 1111222232570358136801719539715135 P E A R S O N C U S T O M L I B R AR Y Table of Contents 1. History, Background, and Basic Concepts James E. Mazur 1 2. Innate Behavior Patterns and Habituation James E. Mazur 27 3. Basic Principles of Classical Conditioning James E. Mazur 51 4. Theories and Research on Classical Conditioning James E. Mazur 79 5. Basic Principles of Operant Conditioning James E. Mazur 105 6. Reinforcement Schedules: Experimental Analyses and Applications James E. Mazur 133 7. Avoidance and Punishment James E. Mazur 159 8. Theories and Research on Operant Conditioning James E. Mazur 187 9. Stimulus Control and Concept Learning James E. Mazur 211 10. Comparative Cognition James E. Mazur 235 11. Learning Motor Skills James E. Mazur 261 12. Learning by Observation James E. Mazur 283 13. Choice James E. Mazur 305 I 333 Index 333 II History, Background, and Basic Concepts LEARNING OBJECTIVES After reading this chapter, you should be able to ■ describe the early theories of memory ■ explain how our sensory receptors respond proposed by the Associationists and the early to “simple sensations” and how feature memory studies of Hermann Ebbinghaus detectors in the visual system respond to ■ explain the behavioral and cognitive more complex patterns approaches to studying learning and how ■ list three main types of changes that can they differ take place in the brain as a result of a ■ explain the advantages and disadvantages learning experience, and present evidence of using animals in psychological research for each type ■ discuss intervening variables, and the debate over whether they should be used in psychology 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 dis- abilities? It was difficult to imagine spending an entire semester on these topics, which sounded fairly narrow and specialized for an introductory-level course. From Chapter 1 of Learning and Behavior, Seventh Edition. James E. Mazur. Copyright © 2013 by Pearson Education, Inc. All rights reserved. 1 History, Background, and Basic Concepts My conception of the psychology of learn- type of behavior, many different questions would ing was wrong in several respects. First, a psychol- probably come to mind. Some questions might ogy course emphasizing learning in the classroom deal with the learning process itself: Did the ani- would probably have a title such as “Educational mal open the can purely by accident, or was it Psychology” rather than “Learning.” My second guided by some “plan of action”? What factors error was the assumption that the psychology of determine how long the raccoon will persist in learning is a narrow field. A moment’s reflection manipulating the garbage can if it is not imme- reveals that students do not have a monopoly on diately successful in obtaining something to eat? learning. Children learn a great deal before ever Such questions deal with what might be called the entering a classroom, and adults must continue to acquisition phase, or the period in which the ani- adapt to an ever-changing environment. Because mal is acquiring a new skill. learning occurs at all ages, the psychological dis- Once the raccoon has had considerable cipline of learning places no special emphasis on experience in dealing with garbage cans, it may the subset of learning that occurs in the class- encounter few surprises in its expeditions through room. Furthermore, since the human being is the neighborhood. Although the acquisition only one of thousands of species on this planet process is essentially over as far as garbage cans are that have the capacity to learn, the psychological concerned, we can continue to examine the rac- discipline of learning is by no means restricted coon’s behavior, asking somewhat different ques- to the study of human beings. For reasons to be tions that deal with the performance of learned explained, a large percentage of all psychological behaviors. The raccoon will have only intermittent experiments on learning have used nonhuman success in obtaining food from garbage cans— subjects. Though they may have their faults, psy- sometimes a can will be empty and sometimes it chologists in the field of learning are not chauvin- will contain nothing edible. How frequently will istic about the human species. the raccoon visit a given backyard, and how will Although even specialists have difficulty the animal’s success rate affect the frequency of defining the term learning precisely, most would its visits? Will its visits occur at the most advan- agree that it is a process of change that occurs as a tageous times of the day or week? Such questions result of an individual’s experience. Psychologists concern the end product of the learning process, who study learning are interested in this process the raccoon’s new behavior patterns. This text is wherever it occurs—in adults, in school children, entitled Learning and Behavior, rather than simply in other mammals, in reptiles, and in insects. This Learning, to reflect the fact that the psychology of may sound like a large subject matter, but the field learning encompasses both the acquisition process of learning is even broader than this, because re- and the long-term behavior that results. searchers in this area study not only the process of learning but also the product of learning—the The Search for General long-term changes in an individual’s behavior that PrinciPleS of learninG result from a learning experience. An example may help to clarify the distinc- Because the psychology of learning deals with tion between process and product. Suppose you all types of learning and learned behaviors in glance out the window and see a raccoon near all types of creatures, its scope is broad indeed. some garbage cans in the backyard. As you watch, Think, for a moment, of the different behaviors the raccoon gradually manages to knock over a you performed in the first hour or two after ris- garbage can, remove the lid, and tear open the ing this morning. How many of those behaviors garbage bag inside. Imagine that the smell of food would not have been possible without prior learn- attracted the raccoon to the garbage cans, but ing? In most cases, the decision is easy to make. that it has never encountered such objects before. Getting dressed, washing your face, making your If we were interested in studying this particular bed, and going to the dining room for breakfast 2 History, Background, and Basic Concepts 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 selec- tion of appropriate types and quantities of food, the proper use of utensils, and the development of coordinated hand, eye, and mouth move- ments. Except for behaviors that must occur c ontinuously for a person to survive, such as breathing and the beating of the heart, it is dif- ficult to think of many human behaviors that do not depend on prior learning. Considering all of the behaviors of hu- fiGure 1 An experimental chamber in which a mans and other creatures that involve learning, rat can receive food pellets by pressing a lever. The the scope of this branch of psychology may seem pellets are delivered into the square opening below the lever. This chamber is also equipped with lights hopelessly broad. How can any single discipline and a speaker so that visual and auditory signals can hope to make any useful statements about all these be presented. (Photo courtesy of James E. Mazur). different instances of learning? It would make no sense to study, one by one, every different example This strategy of searching for general prin- of learning that one might come across, and this is ciples is certainly not unique to the psychology not the approach of most researchers who study of learning. Attempts to discover principles or learning. Instead, their strategy has been to select laws with wide applicability are a part of most a relatively small number of learning situations, s cientific endeavors. For example, a general study them in detail, and then try to generalize principle in physics is the law of gravity, which from these situations to other instances of learn- predicts, among other things, the distance a ing. Therefore, the goal of much of the research freely falling object will drop in a given period of on learning has been to develop general principles time. If an object starts from a stationary posi- that are applicable across a wide range of species tion and falls for t seconds, the equation d = 16t2 and learning situations. predicts the distance (in feet) that the object will B. F. Skinner, one of the most influential fig- fall. The law of gravity is certainly a general prin- ures in the history of psychology, made his belief ciple, because in theory it applies to any falling in this strategy explicit in his first major work, The object, whether a rock, a baseball, or a skydiver. Behavior of Organisms (1938). In his initial stud- Nevertheless, the law of gravity has its limita- ies, Skinner chose white rats as subjects and lever tions. As with most scientific principles, it is ap- pressing as a response. An individual rat would be plicable only when certain criteria are met. Two placed in a small experimental chamber containing restrictions on the equation are that it applies little more than a lever and a tray into which food (1) only to objects close to the earth’s surface, and was occasionally presented after the rat pressed (2) only as long as no other force, such as air re- the lever. A modern version of such a chamber is sistance, plays a role. If we chose to ignore these shown in Figure 1. In studying the behavior of rats criteria, it would be easy to “disprove” the law of in such a sparse environment, Skinner felt that he gravity. We could simply drop a rock and a leaf could discover principles that govern the behavior and show that the leaf falls much more slowly. of many animals, including human beings, in the But once the restrictions on the law of gravity more complex environments found outside the are acknowledged, our experiment proves noth- psychological laboratory. ing, because we did not eliminate the influence 3 History, Background, and Basic Concepts of air resistance. This example shows why it is chapter will introduce a third approach to study- frequently necessary to retreat to the laboratory ing learning—the physiological approach—which to perform a meaningful test of a scientific prin- e xamines what happens in the brain and in indi- ciple. In the laboratory, the role of air resistance vidual nerve cells when we learn. can be minimized through the use of a vacuum chamber. The leaf and the rock will fall at the same rate in this artificial environment, thereby The aSSociaTioniSTS verifying the law of gravity. For similar reasons, aristotle orderly principles of learning and behavior that might be obscured by many extraneous factors in The Greek philosopher Aristotle (c. 350 B.C.) is gen- the natural environment may be uncovered in a erally acknowledged to be the first Associationist. laboratory environment. He proposed three principles of association that Once the restrictions on the law of gravity can be viewed as an elementary theory of memory. are specified, a naive reader might conclude that Aristotle suggested that these principles describe the law has no practical use, because the natu- how one thought leads to another. Before read- ral environment provides no vacuums near the ing about Aristotle’s principles, you can try some- earth’s surface. However, this conclusion is cor- thing Aristotle never did: You can conduct a simple rect only if extremely precise measurements are experiment to test these principles. This experiment, demanded, because for many solid objects with a which should take only a minute or two, can be roughly spherical shape, the role of air resistance called a study of free association. Get a piece of is so negligible that the law of gravity makes rea- paper and a pencil, and write numbers 1 through 12 sonably accurate predictions. Similarly, it would in a column down the left side of the paper. Figure be naive to assume that a psychological principle 2 contains a list of words also numbered 1 through has no relevance to the natural environment sim- 12. Reading one word at a time, write down the ply because that principle is most clearly demon- first two or three words that come to mind. Do not strated in the laboratory. spend much time on any one word—your first few Within the field of psychology, researchers responses will be the most informative. have studied the topic of learning in several dif- Once you have your list of responses to ferent ways. The remainder of this chapter gives the 12 words, look over your answers and try an overview of these different approaches, plus a to formulate some rules that describe the types brief history of the field. We will begin with some of responses you made. Can you guess any of of the earliest recorded thoughts about learning Aristotle’s three principles? Aristotle’s first prin- and memory, developed by philosophers called ciple of association was contiguity: The more Associationists and later tested by the psycholo- closely together (contiguous) in space or time gist Hermann Ebbinghaus. We will then ex- two items occur, the more likely will the thought amine and compare two modern approaches of one item lead to the thought of the other. For to learning—the behavioral and cognitive example, the response chair to the word table approaches—and how they differ. Finally, this 1. apple 7. girl 2. night 8. dentist 3. thunder 9. quiet 4. bread 10. sunset 5. chair 11. elephant 6. bat 12. blue fiGure 2 Words for the free-association experiment. 4 History, Background, and Basic Concepts illustrates association by spatial contiguity, since concept a person has is based on one or more the two items are often found close together. The previous experiences. response lightning to the word thunder is an ex- The opposite of Empiricism is Nativism, ample of association by temporal contiguity. or the position that some ideas are innate and do Other examples of association by contiguity are not depend on an individual’s past experience. bread-butter and dentist-pain. For instance, the Nativist Immanuel Kant (1781) Aristotle’s other two principles of association believed that the concepts of space and time are were similarity and contrast. He stated that the inborn and that through experience new con- thought of one concept often leads to the thought cepts are built on the foundation of these origi- of similar concepts. Examples of a ssociation by nal, innate concepts. The Empiricist position is similarity are the responses orange or pear to the the more extreme of the two because it allows for prompt apple, or the responses yellow or green no counterexamples—it takes just one example of to the prompt blue. By contrast, Aristotle meant an innate concept to refute the Empiricist posi- that an item often leads to the thought of its op- tion. Modern research has uncovered numerous posite (e.g., night-day, girl-boy, sunset-sunrise). examples that contradict the extreme Empiricist Most people who try this simple free-association position. experiment conclude that Aristotle’s principles of Fortunately, Associationism is not logi- association have both strengths and weaknesses. cally tied to extreme Empiricism. We can grant On the negative side, the list of principles seems that some concepts are innate but many con- incomplete; other factors that affect the train of cepts are developed through experience. The thought may have already occurred to you. On the British Empiricists offered some hypotheses positive side, Aristotle’s principles have some in- both about how old concepts become associat- tuitive validity for most people, and they seem to ed in memory and about how new concepts are be a reasonable first step in the development of a formed. According to the Associationists, there is theory about the relationship between experience a direct correspondence between experience and and memory. memory. Experience consists of sensations, and memory consists of ideas. Furthermore, any sen- sory experience can be broken down into simple The British associationists: sensations. For instance, if a person observes a Simple and complex ideas red box-shaped object, this sensation might be For Aristotle, the principles of association were broken down into two simple sensations: red simply hypotheses about how one thought leads and rectangular. At some later time, the person’s to another. For many of the philosophers who memory of this experience would consist of the wrote about Associationism several centuries two corresponding simple ideas of red and rectan- later, this topic assumed a much greater sig- gular. Thus, as illustrated in Figure 3a, there is a nificance: Associationism was seen as a theory one-to-one correspondence between simple sen- of all knowledge. The British Associationists sations and simple ideas. A simple idea was said included Thomas Hobbes (1651), John Locke to be a sort of faint replica of the simple sensation (1690), James Mill (1829), and John Stuart Mill from which it arose. (1843). These writers are also called the British Now suppose that the person repeatedly en- Empiricists because of their belief that every per- counters such a red box-shaped object. Through son acquires all knowledge empirically, that is, the principles of contiguity, an association should through experience. This viewpoint is typified by develop between the ideas of red and rectangle, as John Locke’s statement that the mind of a new- shown in Figure 3b. Once such an association is born child is a tabula rasa (a blank slate) on which formed, if the person experiences the color red, experience makes its mark. The Empiricists be- this will not only invoke the idea of red, but by lieved that every memory, every idea, and every 5