Science moves through history along many routes and at many speeds. There are slow times, all too frequently, when it seems to stagnate, making little or no progress. Then there are those exciting, dynamic periods when new discoveries spark waves of dialog, attention, research, and progress. These discoveries quite literally change what we know about how the world works. The history of psychology is no different from the other sciences. There has been psychological research that has had remarkable and lasting effects on the various disciplines that comprise the science we call psychology. The findings generated from these studies have changed our knowledge of human behavior, and they have set the stage for countless subsequent projects and research programs. Even when the results of some of these pivotal studies have later been drawn into controversy and question, their effect and influence in a historical context never diminishes. They continue to be cited in new articles; they continue to be the topic of academic discussion; they continue to form the foundation for textbook chapters; and they continue to hold a special place in the minds of psychologists.
The concept for this book grew out of my many years of teaching psychology. Psychology textbooks are based on those key studies that have shaped the science of psychology over its relatively brief history. Textbooks, however, seldom give the original studies the attention they richly deserve. Usually the research processes are summarized and diluted to the point that little of the life and excitement of the discoveries remain. Sometimes the way the methods and findings are reported can even mislead the reader about the study's true impact and influence. This is in no way a criticism of the textbook writers who work under length constraints and must make many difficult choices as to what gets included and in how much detail. The situation is, however, unfortunate, since the foundation of all of psychology is research, and it is through a century of ingenious and elegant studies that our knowledge and understanding of human behavior have been expanded and refined to the level of sophistication that exists today.
This book is an attempt to fill the rather large gap between the psychology textbooks and the research that made them possible. It is a journey through the headline history of psychology. My hope is that the way the 40 chosen studies are presented will bring them back to life so that you can experience them for yourself. This book is intended for anyone who wishes a greater understanding of the true roots of psychology.
CHOOSING THE STUDIES
The studies included in this book were carefully chosen from those found in psychology texts and journals and from those suggested by leading authorities in psychology's many subfields. The number wasn't planned, but as the studies were selected, 40 seemed to be about right both from a historical point of view and in terms of length. The studies chosen are arguably the most famous, the most important, or the most influential in the history of psychology. I use the word arguably since many who read this book may wish to dispute some of the choices. One thing is sure: There is no single list of 40 studies that would satisfy everyone. However, the studies included here are the ones that continue to be cited most frequently, stirred up the most controversy when they were published, sparked the most subsequent related research, opened new fields of psychological exploration, or changed most dramatically our knowledge of human behavior. These studies are organized according to the subfield into which they best fit, including Biology and Human Behavior; Consciousness; Learning and Conditioning; Intelligence, Cognition, and Memory; Human Development; Emotion and Motivation; Personality; Psychopathology; Psychotherapy; and Social Psychology.
PRESENTING THE STUDIES
A basic format is used consistently throughout the book to promote a clear understanding of each study presented. Each chapter contains:
- An exact, readily available reference for where the original study can be found.
- A brief introduction summarizing the background in the field leading up to the study and the reasons the researcher carried out the project.
- The theoretical propositions or hypotheses on which the research rests.
- A detailed account of the experimental design and methods used to carry out the research, including, where appropriate, who the subjects were and how they were recruited; descriptions of any apparatus and materials used; and the actual procedures followed in carrying out the research.
- A summary of the results of the study in clear, understandable, nontechnical, nonstatistical, no jargon language.
- An interpretation of the meaning of the findings based on the author's own discussion in the original article.
- The significance of the study to the field of psychology.
- A brief discussion of supportive or contradictory follow-up research findings and subsequent questioning or criticism from others in the field.
- A sampling of recent applications and citations of the study in others' articles to demonstrate its continuing influence.
- References for additional and updated reading relating to the study.
Often, scientists speak in languages that are not easily understood (even by other scientists!). The primary goal of this book is to make these discoveries meaningful and accessible to the reader, to allow you to experience the excitement and drama of these remarkable and important discoveries. Where possible and appropriate, the studies presented here have been simplified and edited for ease of reading and understanding. However, this has been done in such a way that the meaning and elegance of the work is preserved and the impact of the research is distilled and clarified.
NEW TO THE FOURTH EDITION
This fourth edition of Forty Studies contains many significant and substantive changes and additions including two important new studies and updates in all of the "Recent Applications" sections near the end of each reading, reflecting the numerous citations of each of the 40 studies in articles from professional journals during the three years since the completion of the third edition (1998-2000). The findings of over 60 new studies from those three years are briefly summarized to allow you to experience the ongoing influence of these 40 studies that changed psychology. The new studies are fully referenced at the end of each chapter along with other relevant sources. As you read through them, you will be able to appreciate the breadth and richness of the contributions still being made by the 10 studies that comprise this book.
Over the three years since completing the third edition, I have enjoyed numerous conversations with and received helpful suggestions and counsel from colleagues in many psychology subfields about potential changes in the selection of studies for this new edition. Two research areas that have been expanding in their influence over the past 20 years or so have been central to many of my communications from the field, and, consequently, have been added to this book. Interestingly, both are at the core of opposite sides of the nature-nurture debate.
One of these is an article representing the recent (and current) swing of the philosophical pendulum from the broad focus on environmental influences that dominated psychology for most of the second half of the twentieth century, to a new recognition that inherited; genetic forces appear to play a much stronger role than anyone since Sigmund Freud has contemplated. A great deal of the evidence for this new biological focus has emanated from Drs. Thomas Bouchard and David...