Facts About Psychological Disorders

Psychologists Edward Thorndike, John Watson, Clark Hull, and B. F. Skinner spearheaded behaviorism, focusing on directly observable behaviors rather than unobservable mental processes and mental contents. They investigated the association between a behavior and its consequence, and proposed scientifi cally testable mechanisms to explain how maladaptive behavior arises. Behaviorism helps explain how maladaptive behavior can arise from previous associations with an object, situation, or event. Behaviorism led to innovative treatments.


Ivan Pavlov discovered and investigated what is sometimes referred to as Pavlovian conditioning—the process whereby a refl exive behavior comes to be associated with a stimulus that precedes it. Pavlovian conditioning helps explain the severe fears and anxieties that are part of some psychological disorders: Neutral stimuli that have in the past been paired with fear-inducing objects or events can subsequently, by themselves, induce fear or anxiety.


Cognitive psychology has led to the scientific investigation of mental processes that affect how people pay attention to stimuli and develop biases in what they expect and remember. Such biases in turn can confi rm the inaccurate views that perpetuate a psychological disorder. Aaron Beck and Albert Ellis each focused on how people’s irrational and inaccurate thoughts about themselves and the world can contribute to psychological disorders, and each developed a type of treatment to address the irrational and inaccurate thoughts.

Social forces that help explain psychological disorders include diffi culties with attachment and the role of relationships in buffering negative life events.


The discovery of the biological cause of one type of mental illness—general paresis—led to investigations into possible biological causes of other types of mental illness. Although researchers investigate various biological and neurological abnormalities to understand psychopathology, exclusively biological explanations ultimately strip mental disorders of the context in which they occur and provide a false impression that mental disorders arise from biological (primarily neurological) factors alone.

Psychological disorders cannot be fully explained by any single type of factor or theory. One approach to integrating different factors is the diathesis–stress model, which proposes that if a person has a predisposition to a psychological disorder, stressors may trigger its occurrence.


The biopsychosocial approach rests on the idea that both diathesis and stress can be grouped into three types of factors: biological, psychological, and social. As research on biological factors associated with psychological disorders has advanced, the important effects of the brain on other biological functions have become clear. In addition, recent research allows investigators to begin to understand the feedback loops among the three types of factors. For these reasons, this book uses the term neuropsychosocial rather than biopsychosocial.