1 Chapter 1 Introduction

Welcome to Abnormal Psychology! As you’ll read more about in this chapter, abnormal psychology refers to the scientific study of people who are exhibiting behaviour that seems atypical or unusual, with the intent to be able to reliably predict, explain, diagnose, identify the causes of, and treat maladaptive behavior. Abnormal psychology is one of the largest sub-fields in psychology, representing a great deal of research and applied work trying to understand and cure mental disorders. As you will see from the first part of this chapter, and as you learn more in this book, the costs of mental illness are substantial.

This chapter will introduce you broadly to important concepts, definitions, and terminology in abnormal psychology that will frame the rest of your learning. It reviews how to define mental disorder as well as the strengths and limitations of our current diagnostic approaches. You’ll read, as well, about how culture and cultural expectations influence our views on abnormality. We cannot examine abnormality without taking cultural norms into account.

In this chapter you will also learn about how mental health professionals assess individuals who might be experiencing a mental disorder, some important concepts for measurement like validity and reliability, and read an overview of some of the many different tools these professionals use to conduct their assessments. Last, you’ll learn how these professionals diagnose and classify abnormal behaviour.