Abnormal behavior, often referred to as mental illness, results from changes in brain function that influence thought patterns, behaviors, and social interactions. Psychologists and psychiatrists typically assess abnormal behavior using three primary criteria: deviance, maladaptation, and personal distress, particularly when these traits persist over long periods.
Deviant Behavior
Deviance in behavior refers to actions or thought patterns that significantly diverge from societal norms or...

The development of psychological disorders, which are characterized by deviant, maladaptive, and personally distressing behaviors, has been explored through several theoretical approaches.
Biological approach
The biological approach posits that internal, organic factors are the primary causes of such disorders. This perspective emphasizes brain structure and function, genetic predispositions, and neurotransmitter imbalances. For example, schizophrenia has been associated with both genetic...

The Diagnostic and Statistical Manual of Mental Disorders (DSM) serves as the primary classification system for mental health disorders, providing standardized diagnostic criteria for clinicians and researchers. First published by the American Psychiatric Association (APA) in 1952, the DSM has undergone several revisions to reflect evolving psychiatric understanding. The fifth edition, DSM-5, released in 2013, introduced key updates that expanded diagnostic categories and modified diagnostic...

Treatment approaches for psychological disorders fall into three main categories: psychological, biological, and sociocultural. Each approach targets different aspects of mental health, requiring varying levels of education and training.
Psychological therapies focus on modifying emotions, thoughts, and behaviors through talking, interpreting, listening, rewarding, challenging, and modeling. Clinical psychologists, counselors, and social workers commonly practice psychotherapy. Clinical...

Personality disorders represent enduring cognition, affect, and behavior patterns that significantly deviate from societal norms. These maladaptive traits often lead to difficulties in various domains, including interpersonal relationships, occupational settings, and overall psychological well-being. Paranoid personality disorder and schizoid personality disorder are two distinct conditions marked by odd or eccentric behavior.
Paranoid Personality Disorder
Paranoid personality disorder is...