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Chapter 12: Abnormal Psychology

Part One: Defining Abnormal Behavior

Part Two: Psychoses, Affective Disorders, and Anxiety Disorders

Part Three: Neurodevelopmental Disorders

Part Four: Somatic, Dissociative, and Personality Disorders

Overview of Chapter 12: Abnormal Psychology

Abnormal Psychology is one of the most common psychology courses on many campuses. It describes serious forms of mental disorders. They are fascinating in themselves, but they also have personal relevance to many students.

About 1 in 3 American families has at least one family member who has required help for a mental or behavioral disorder. Often a student finds information in an Abnormal Psychology course that sheds light on something observed while growing up.

Abnormal psychology also shows us a lot about the nature of human mental life by showing the ways it can go wrong. For example, psychoses (major breaks from reality) make it clear that most of us maintain a strong reality orientation. We take it for granted, but when somebody "loses it" there is a real crisis.

Similarly, anxiety disorders show what happens when alarm circuits in the brain go off too easily. Mood disorders shed light on malfunctions of the hedonic control system.

Somatic disorders highlight mind/body interactions. The more we understand about what makes these systems go wrong, the better we understand normal human behavior.

How this chapter is organized

First we examine the inevitable question: How can abnormal behavior be defined, and how should it be handled by society and by government? We discuss deinstitutional­ization, the policy of releasing from institutions any mentally disordered people who (in theory) pose no danger to themselves or others.

Most people agree that people with mental issues should not be confined unneces­sarily. However, deinstitutional­ization has caused problems. Some people formerly housed in mental institutions end up homeless on the streets or in prisons.

We will survey major categories from DSM-5, the 2013 revision of the Diagnostic and Statistical Manual of the American Psychiatric Association. Whatever one might think of the DSM series (and many psychologists have complaints about it) the DSM class­ification is standard. Every clinical or coun­seling psychologist in the U.S. must be acquainted with it and its international counter­part, the ICD (International Class­ification of Diseases).

We review major disorders seen by clinical psychologists as well as psychiatrists: the psychoses, which are disorders of reality orientation, and mood disorders such as depression, anxiety disorders such as panic attacks, and obsessive-compulsive disorder, which now has a category of its own in DSM-5.

The next part of the chapter deals with neurodevelopmental disorders. We take a look at autism, now defined as a spectrum disorder that can range in severity from severely handicapping to near-normal.

We will discuss attention deficit with hyperactivity (ADHD), widely diagnosed among schoolchildren in the U.S., and dyslexia, which turns up on college campuses as a form of learning disorder in otherwise very intelligent students.

The most common problems, in psych­ological clinics, are personality disorders. We discuss all eleven of them that are mentioned in DSM-5, with special attention to the antisocial personality disorder.

DSM-5 includes far more categories of disorders than can be covered in an introductory psychology course. Many psychological disorders are mentioned in chapters other than this one. See the section below ("Related topics in other chapters") for a some disorders not covered in this chapter.

Related topics in other chapters

A number of syndromes caused by brain damage are covered in Chapter 2 in the section on Neuropsychology. Sleep disorders are in Chapter 3 (States of Consciousness). Amnesia is discussed in Chapter 6 (Memory).

Multiple personality disorder has a page devoted to it in Chapter 11 (Personality Theories) and is briefly described here as a form of dissociative disorder. Treatment of phobias with systematic desensitization is in the chapter on Therapies (Chapter 13).

Addiction and stress-related disorders and the behavioral treatment of chronic pain are all discussed in Chapter 14 (Frontiers of Psychology). Sexual disorders are in Chapter 16 (Sex, Friendship, and Love).

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