A first glance at your textbook might suggest that introductory psychology resembles a cafeteria, consisting of a series of unrelated topics. Here is a little chemistry of the brain, over there a little biology of reproductive systems, and for dessert, a description of social pressures. But unlike a cafeteria, the diversity of topics in the textbook reflects not an attempt to satisfy every taste, but an effort to analyze essential parts of a complex whole. The diversity is necessary because all of these topics are pieces of the puzzle of psychology. If you wanted to understand why a friend became addicted to alcohol, for example, you would want to explore not only the person's history but also his relationships and the effects of chemicals on his brain.

Obviously you cannot study all of these topics at once; you would examine them one at a time. So, too, the textbook focuses on one aspect of psychology at a time. Eventually, however, it helps to put the pieces together. Much as parts of a jigsaw puzzle may take on new meaning when you see where they fit, so too the pieces of psychology take on new dimensions once you see how they are related. For example, the chemical messengers used in the brain (introduced in Chapter 2) are interesting in their own right; but your knowledge about them takes on new significance when you consider how these chemicals can be affected by drugs (discussed in Chapter 4) and by certain treatments for psychological disorders (discussed in Chapter 13).

To help you see how the pieces of psychology fit together, the authors of Essentials of Psychology have paid special attention to the ties among the aspects of human psychology, among the different areas of psychological research, and among the chapters of the textbook. These ties are all forms of what the authors call linkages, and the text highlights them in several ways. First, cross-references and discussions throughout the text point out how topics in one chapter are related to discussions that appear in other chapters. Second, at the end of each chapter, a Linkages diagram presents questions that illustrate a link between the current chapter and the topic of other chapters in the text. These questions are then repeated in the margin next to where they are explored. Finally, a Linkages section discusses in some depth one specific question from the Linkages diagram.

You could read the text profitably without paying special attention to the Linkage elements, but they can help you gain a clearer view of psychology as a whole, a deeper understanding of specific issues, and a framework on which you can build your knowledge of psychology. And when you organize your knowledge and relate one piece of information to another, you improve your ability to remember the information. The Linkages diagrams in particular can be used in many ways as tools for learning and remembering information. Here are some suggestions.

Before reading the chapter, read the questions in the Linkages diagram. They will give you a feeling for the topic of the chapter and for the broader significance of specific issues. In each diagram, some of the questions are discussed in the current chapter and some in other chapters. Can you answer any of the questions? Do any of them concern a topic you have already read about in the text? If so, what do you remember about it? You might go to the page number given after the question, look for the question in the margin on that page, and scan or read the discussion. This will refresh your memory for concepts or facts related to the material to be discussed in the current chapter.

After reading the chapter, you can use the diagram to check your memory and understanding of the chapter. Try writing answers to those questions in the diagram that were discussed in the chapter. Check your answers against the text discussions. (Again, the page numbers in the diagram indicate where the discussion occurs.)

The diagrams can also help you go beyond the textbook in gaining and organizing knowledge of psychology. Suppose you are studying for a final exam and want to check your understanding of the topic of learning. You might go first to the Linkages diagram in the Learning chapter and check whether you can answer the questions; then you might flip to the Linkages diagrams in other chapters, find questions tied to Learning, and try to answer those questions. Also, keep in mind that the diagrams in the text provide only a sampling of linkages; there are many others. Finding additional linkages on your own can further your understanding of psychological issues and improve your memory of the material in the text. Finally, the questions in the Linkages diagrams or linkages that you find yourself may provide interesting topics for term papers.