Psychological Disorders: Classification, Personality, and Dissociative Disorders

Study Guide - Smart Notes

Tailored notes based on your materials, expanded with key definitions, examples, and context.

Defining & Classifying Psychological Disorders

Abnormal Psychology and Historical Approaches

Abnormal psychology is the scientific study of mental illness and maladaptive behavior. Throughout history, societies have developed various approaches to understanding and treating psychological disorders, often reflecting prevailing cultural and medical beliefs.

Maladaptive behavior: Actions or tendencies that cause distress, impair daily functioning, or increase the risk of harm to oneself or others.
Historical treatments included trepanation (drilling holes in the skull to release 'evil spirits') and the use of asylums for the mentally ill.
The medical model treats psychological disorders as illnesses with specific symptoms, causes, and outcomes, similar to physical diseases.
Emil Kraepelin was influential in classifying mental disorders and introducing the concept of psychosis.

Historical painting depicting treatment of madness Portrait of Emil Kraepelin Historical depiction of trepanation Skull with evidence of trepanation Title page of 'A Treatise on Madness'

Example: Trepanation was practiced in ancient cultures as a treatment for mental disturbances, reflecting early beliefs about the causes of psychological disorders.

The Diagnostic and Statistical Manual of Mental Disorders (DSM)

The DSM is the primary classification system for psychological disorders in North America. It provides standardized criteria for diagnosing mental illnesses and has evolved over time to reflect advances in research and clinical practice.

Current edition: DSM-5-TR (Text Revision).
Disorders are now viewed on a severity spectrum (e.g., autism spectrum disorder).
Recent additions include prolonged grief disorder.
Challenges include subjective clinician bias, reliance on self-report, and the potential for stigma due to diagnostic labeling.

Bar graph showing increase in number of disorders across DSM editions

Example: The number of recognized disorders has increased from 106 in DSM-I to 410 in DSM-IV, reflecting greater awareness and research.

Applications of Diagnoses

Diagnoses of psychological disorders have important implications in various settings, including education and the legal system.

Classrooms: Diagnoses such as ADHD (Attention Deficit/Hyperactivity Disorder) help guide interventions for children with hyperactivity, impulsivity, and attention difficulties.
Courtrooms: The "not guilty by reason of insanity" defense relies on the presence of a diagnosable mental disorder that impairs judgment or self-control (e.g., M'Naghten rule).

Example: ADHD diagnoses have increased, possibly influenced by social media and changing societal expectations.

Personality & Dissociative Disorders

Personality Disorders: Definition and Clusters

Personality disorders are enduring patterns of behavior, cognition, and inner experience that deviate markedly from cultural expectations, are inflexible, and lead to distress or impairment. They are grouped into three clusters based on shared features.

Cluster A (Odd/Eccentric): Paranoid, Schizoid, Schizotypal Personality Disorders
Cluster B (Dramatic/Emotional/Erratic): Borderline, Narcissistic, Histrionic, Antisocial Personality Disorders
Cluster C (Anxious/Fearful): Avoidant, Dependent, Obsessive-Compulsive Personality Disorders

Table summarizing personality disorder clusters and features

Cluster A: Odd or Eccentric Disorders

Cluster A disorders are characterized by social detachment, suspiciousness, and eccentric behaviors.

Paranoid Personality Disorder: Persistent distrust and suspicion of others, often interpreting their motives as malevolent.
Schizoid Personality Disorder: Detachment from social relationships and limited emotional expression.
Schizotypal Personality Disorder: Acute discomfort in close relationships, cognitive or perceptual distortions, and eccentric behavior.

Diagram of the superior temporal gyrus, relevant to schizotypal disorder Cycle of paranoid cognition and emotion

Example: Individuals with paranoid personality disorder may misinterpret benign social cues as threatening, leading to chronic vigilance for new threats.

Cluster B: Dramatic, Emotional, or Erratic Disorders

Cluster B disorders involve problems with impulse control, emotional regulation, and interpersonal relationships.

Borderline Personality Disorder (BPD): Instability in mood, self-image, and relationships; impulsivity; intense fear of abandonment.
Narcissistic Personality Disorder (NPD): Grandiosity, need for admiration, and lack of empathy; underlying self-doubt and fear of abandonment.
Histrionic Personality Disorder: Excessive emotionality and attention-seeking behavior.
Antisocial Personality Disorder (APD): Disregard for the rights of others, lack of empathy, and violation of social norms; often resistant to treatment.

Physiological response comparison in APD Brain regions implicated in personality disorders

Example: People with APD show reduced physiological responses to threatening or distressing images, indicating emotional blunting.

Cluster C: Anxious or Fearful Disorders

Cluster C disorders are marked by anxiety, fearfulness, and behavioral inhibition.

Avoidant Personality Disorder: Social inhibition, feelings of inadequacy, and hypersensitivity to negative evaluation.
Dependent Personality Disorder: Excessive need to be taken care of, leading to submissive and clinging behavior.
Obsessive-Compulsive Personality Disorder (OCPD): Preoccupation with orderliness, perfectionism, and control at the expense of flexibility and efficiency.

Example: OCPD differs from OCD in that the former involves personality traits rather than intrusive thoughts and compulsive behaviors.

Dissociative Disorders

Dissociative disorders involve disruptions in consciousness, memory, identity, or perception. The most well-known is Dissociative Identity Disorder (DID).

Dissociation: A psychological state in which a person feels disconnected from their thoughts, feelings, or sense of identity.
Dissociative Identity Disorder (DID): Formerly known as multiple personality disorder, DID is characterized by the presence of two or more distinct identities or personality states that recurrently take control of the individual's behavior.
DID is often associated with severe childhood trauma and is a controversial diagnosis due to questions about its validity and prevalence.

Movie poster for 'Split', a film depicting DID

Example: Individuals with DID may experience amnesia for everyday events and feel as though different aspects of themselves are separate people.

Additional info: The DSM-5-TR continues to refine diagnostic criteria to improve reliability and validity, and ongoing research explores the biological, psychological, and social factors contributing to these disorders.