Psychological Disorders: Definitions, Perspectives, and Major Classes

Psychological Disorders

Introduction

Psychological disorders, also known as mental disorders, are patterns of behavioral or psychological symptoms that impact multiple areas of life. These disorders create distress for the person experiencing these symptoms. This guide explores the definition, historical perspectives, major theoretical models, and the main classes of psychological disorders.

Defining Abnormal Behavior

What is Abnormal?

Abnormal behavior is a social construct and is typically judged using the "3 D's":

• Distressing: Causes distress to self or others.

• Dysfunctional: Interferes with daily functioning for the person or society.

• Deviant: Violates social norms or expectations.

Judgments of abnormality often require considering all three aspects.

Historical Perspectives on Abnormal Behavior

Historical Conceptions

• Major psychological disorders have existed in all cultures and time periods.

• Examples from history:

  • Homer's Odyssey: Early literary references to abnormal behavior.

  • Hippocrates's Four Humors: Ancient Greek theory attributing mental illness to imbalances in bodily fluids.

  • Freud's Psychosexual Stages: Early psychological model of development and disorder.

Three Dominant Traditions

• Supernatural: Disorders as results of supernatural forces (e.g., possession).

• Biological: Disorders as diseases affecting the brain (e.g., Hippocrates, 5th Century B.C.).

• Psychological: Disorders as results of psychological processes.

Demonological View

• Abnormal behavior attributed to supernatural forces or spirit possession.

• Treatment: Trephination (drilling a hole in the skull) was used to release spirits.

Early Biological Views

• Mental illnesses viewed as diseases like physical illnesses affecting the brain.

• Breakthrough: General paresis (a mental disorder) was found to be caused by syphilis, linking some disorders to physical causes.

• Current understanding includes both physiological and psychological factors.

Major Theoretical Perspectives

• Psychoanalytic: Inappropriate use of defense mechanisms leads to neuroses; withdrawal from reality leads to psychoses.

• Behavioural: Disorders are learned responses to the environment.

• Cognitive: Disorders arise from maladaptive thought processes.

• Humanistic: Disorders result from frustrations in achieving self-actualization and negative self-concept.

Vulnerability-Stress Model

Overview

The vulnerability-stress model explains psychological disorders as the result of an interaction between biological, environmental, and psychological factors.

• Vulnerability: Predisposition to disorders due to biological basis, personality, or environmental factors.

• Predisposition: A disorder develops only when a person with vulnerability is exposed to a stressor.

• Stressor: An event that requires the person to cope, potentially triggering the disorder.

Major Classes of Psychological Disorders

Anxiety Disorders

Anxiety disorders are characterized by excessive fear or anxiety that is out of proportion to the situation and interferes with daily life.

• Examples: Phobias, generalized anxiety disorder, obsessive-compulsive disorder (OCD).

Biological Factors

• Genetics: Monozygotic (MZ) twins are more similar than dizygotic (DZ) twins in anxiety disorders.

• GABA: Low levels may cause highly reactive nervous systems.

Gender Differences

• Females exhibit more anxiety disorders than males, with differences emerging as early as age seven.

Psychological Factors

• Psychodynamic: Neurotic anxiety arises when unacceptable impulses threaten to overwhelm the ego's defenses.

• Cognitive: Maladaptive thoughts and beliefs; catastrophic appraisals of situations.

Learning Explanations

• Classical Conditioning: Associating an object or situation with pain or trauma.

• Modeling: Learning by observing others.

Sociocultural Factors

• Cultural definitions of what is important influence the types of anxiety disorders seen (e.g., culture-bound syndromes).

Mood (Affective) Disorders

Mood disorders involve disturbances in emotional state, ranging from severe depression to extreme elation (mania).

• Depression: Not just sadness; clinical depression involves symptoms that are frequent, intense, and out of proportion to the situation.

• Major Depression: Inability to function effectively.

• Dysthymia: Chronic disruption of mood.

Symptoms of Depression

Domain	Symptoms
Emotional	Negative mood state
Cognitive	Difficulty concentrating, feelings of inferiority and failure, pessimism
Motivational	Loss of interest and drive
Somatic	Appetite loss, compulsive eating, sleep disturbances

Prevalence and Gender Differences

• 1 in 20 North Americans is severely depressed.

• 1 in 5 will have a depressive episode of clinical proportions during their lifetime.

• Women are twice as likely to suffer from unipolar depression; no gender difference for bipolar disorder.

Biological Explanations

• Depression: Genetic factors, biochemical differences, underactivity of norepinephrine, dopamine, and serotonin.

• Bipolar Disorder: Stronger genetic component than unipolar depression; 50% have a relative with the disorder.

Cognitive Processes

• Depressive Cognitive Triad: Negative thoughts about the world, oneself, and the future.

• Inability to suppress negative thoughts; recall more failures than successes.

• Depressive Attributional Pattern: Success attributed to external factors; negative outcomes attributed to personal factors.

• Learned Helplessness: Expectation that bad events will occur and inability to cope with them.

Learning and Environmental Factors

• Loss of reinforcement and social support can lead to depression.

• Poor parenting, stressful experiences, and failure to develop coping skills or a positive self-concept increase risk.

Sociocultural Factors

• Prevalence of depressive disorders is lower in Hong Kong and Taiwan than in the West.

• Feelings of guilt and inadequacy are highest in North America and Western Europe.

Schizophrenia

Schizophrenia is a severe psychological disorder characterized by disturbances in thought, perception, emotion, and behavior. The term means "split-mind," but it does not refer to multiple personalities.

• Severe Disturbances:

  • Thinking: Delusions (false beliefs)

  • Speech: Disorganized, strange words

  • Perception: Hallucinations (false perceptions)

  • Emotion: Blunted or inappropriate affect

  • Behavior: Disorganized or abnormal behavior

Categories of Schizophrenia

Type I	Type II
Predominance of positive symptoms Pathological extremes Delusions, hallucinations, disordered speech & thought	Predominance of negative symptoms Absence of normal reactions Lack of emotion, expression, motivation

Prevalence and Outcomes

• Affects about 1% of the population; equal numbers of males and females.

• 10% are permanently impaired, 65% have intermittent periods of functioning, and 25% recover.

• Negative symptoms are associated with poor recovery; positive symptoms with better prognosis.

Biological Factors

• Genetics: Higher concordance rate among twins.

• Brain: Neurodegenerative hypothesis (atrophy and destruction of neural tissue).

• Thalamus: Abnormal MRI activity; routes sensory information.

Biochemical Factors

• Dopamine Hypothesis: Overactivity of the dopamine system is linked to schizophrenia.

• Dopamine regulates emotion, motivation, and cognitive functioning.

• Antipsychotic drugs reduce dopamine activity to treat symptoms.

Summary Table: Major Perspectives on Psychological Disorders

Perspective	Main Idea	Example
Psychoanalytic	Disorders arise from unconscious conflicts and defense mechanisms	Freud's theory of neuroses and psychoses
Behavioural	Disorders are learned through conditioning	Phobias acquired via classical conditioning
Cognitive	Disorders result from maladaptive thought patterns	Depressive cognitive triad
Humanistic	Disorders stem from blocked self-actualization	Negative self-concept

Additional info: Some slides referenced YouTube videos for further illustration of disorders (e.g., OCD, BPD, Schizophrenia). These are not included in the notes but may be useful for visual learning.