Psychological Disorders: Prevalence, Types, and Impact (PSYC*1000, Chapter 15 Study Notes)

Week 12: Mental Health (Psychological Disorders)

Introduction

This section covers the major psychological disorders, their prevalence, symptoms, and impact on individuals and society. It is based on Chapter 15 of the Introduction to Psychology course, focusing on mental health, illness, and related stigma.

Mental Disorder – Mental Illness

Definitions and Concepts

• Mental Disorder and Mental Illness are often used interchangeably, but there is no universal agreement among professionals about their precise definitions.

• A mental disorder is a pattern of mental symptoms causing significant problems in life.

• Can develop in a relatively short time.

• Also known as psychopathology.

• Causes distress beyond what is normal, typical, or culturally appropriate.

• Exists on a continuum from healthy to disordered.

• Some personality traits may overlap with symptoms of mental disorders.

Prevalence of Mental Illness in Canada

Statistics and Overview

Estimated one-year prevalence of mental illnesses among adults in Canada (Public Health Agency of Canada, 2020):

Mental Illness	Estimates of One-Year Prevalence
Mood disorders	Major (unipolar) depression: 4.1–4.6% Dysthymia: 0.4–0.8%
Schizophrenia	Less than 1 percent
Anxiety disorders	12.2%
Personality disorders	Less than 0.1%
Anorexia	0.3% women, 0.2% men
Bulimia	1.5% women, 0.1% men

Anxiety Disorders

Overview and Features

• Approximately 1/3 of Canadians have experienced an anxiety disorder.

• Cluster of mental disorders involving excessive anxiety.

• Distinguished from normal anxiety by unreasonably high degree, duration, and source.

• Most anxieties are transient and can be adaptive, but anxiety disorders are excessive and inappropriate.

Potential Causes

• Observational learning: Fears can be learned by observing others or hearing misinformation.

• Anxious thinking: Anxious individuals interpret the world differently from non-anxious people.

• Catastrophic thinking: Predicting terrible events despite low probability.

• One of the most prevalent and earliest onset of all disorder classes; affects 12% of Canadians.

• Since COVID-19, anxiety disorders have increased threefold in Canada.

Generalized Anxiety Disorder (GAD)

• Characterized by high levels of anxiety over a long period, difficult to control.

• Symptoms: feeling tense, on edge, tired, irritable, difficulty concentrating/sleeping.

• Physical symptoms: trembling, palpitations, sweating, dizziness, nausea, diarrhea, frequent urination.

• More prevalent in women.

Obsessive-Compulsive Disorder (OCD)

• Considered an anxiety disorder.

• Marked by distressing, maladaptive focus on details and control; perfectionist-like.

• Condition involves repeated and lengthy immersion in obsessions, compulsions, or both (at least one hour per day).

• Obsessions: Persistent ideas, thoughts, or impulses that are unwanted and cause distress.

• Compulsions: Repetitive behavior or mental act performed to reduce or prevent stress.

• Distress is relieved by compulsions.

• Link to Parkinson’s disease and dopamine dysfunction.

Mood Disorders

Overview

• Over 14% of Canadians will experience a mood disorder.

• Includes depression and bipolar disorders.

• Moods or emotions are extreme or unwarranted.

• Characterized by a general emotional state or mood that is distorted or inconsistent and interferes with functioning.

• Complex interplay of biological, psychological, and social influences.

• Major life events can be precursors.

• Different models conceptualize mood disorders based on nature and nurture.

Types and Symptoms

Disorder/Condition	Symptoms
Major depressive disorder	Chronic or recurrent state with lingering depressed mood, diminished interest, weight loss, sleep difficulties.
Persistent depressive disorder (dysthymia)	Low-level depression for at least two years; feelings of inadequacy, sadness, low energy, poor appetite, decreased productivity, hopelessness.
Manic episode	Inflated self-esteem, grandiosity, decreased need for sleep, more talkative, flight of ideas, distractibility, increased activity, risky behavior.
Hypomanic episode	Less intense and disruptive version of a manic episode.
Bipolar disorder I	Presence of one or more manic episodes.
Bipolar disorder II	At least one episode of major depression and one hypomanic episode.

Disorder/Condition	Symptoms
Cyclothymic disorder	Moods alternate between hypomanic and depressive symptoms; increases risk of bipolar disorder.
Postpartum depression	Depressive episode after childbirth; can include psychotic symptoms, risk of harm to self or infant.
Seasonal affective disorder	Depressive episode with seasonal pattern, often beginning in fall or winter.
Disruptive mood dysregulation disorder	Children under 18 with persistent irritability and frequent episodes of extreme, out-of-control behavior.
Premenstrual dysphoric disorder	Occurs in females during the final week before menses; marked mood lability, irritability, anger.

Major Depressive Disorder (MDD)

• Most common, affecting 16% of the general population.

• More prevalent in females; most likely to develop in 30s.

• Features: overwhelming sadness, despair, hopelessness, loss of pleasure.

• Causes:

  • Biological perspective: Genetic inheritance, brain chemistry (norepinephrine, serotonin, dopamine).

  • Cognitive perspective: Distortions in thinking.

Bipolar Disorder

• Manic episodes and depression, with "normal" periods in between.

• Manic episode: Excessive euphoria, inflated self-esteem, wild optimism, hyperactivity, lowered need for sleep, extremes in behavior.

• Equally common in men and women.

• Heavily genetically influenced; stressful life events can trigger episodes.

Suicide in Canada

Statistics and Risk Factors

• In 2023, suicide was the 12th leading cause of death in Canada; 3rd for children and adolescents.

• Approximately 12 Canadians die by suicide each day.

• Men complete suicide 4x more often than women; women attempt suicide 4x more often than men.

• Over 90% of people who complete suicide had a mental health disorder.

• 12–20% of children have suicidal ideation.

• Suicide accounts for 38% of deaths among Indigenous youth.

Warning Signs of Suicide

• The mnemonic IS PATH WARM? summarizes warning signs:

  • Ideation

  • Substance Abuse

  • Purposelessness

  • Anxiety

  • Trapped

  • Hopelessness

  • Withdrawal

  • Anger

  • Recklessness

  • Mood Changes

Personality Disorders

Definition and Prevalence

• According to the American Psychiatric Association (APA), a personality disorder exists when personality traits are inflexible and maladaptive, causing significant impairment in social or occupational functioning or subjective distress.

• Approximately 6–15% of Canadians live with a personality disorder; onset in adolescence or early adulthood.

• Personality disorders can be comorbid with other mental illnesses.

• The term itself can be stigmatizing.

Manifestations

• Cognition: Distorted perceptions and interpretations of others, events, and self.

• Affectivity: Emotional intensity and mood fluctuations, often inappropriate.

• Interpersonal functioning: Varies from enmeshment to disconnectedness.

• Impulse control: Poor control, risk for injury to self or others.

DSM-5 Categories of Personality Disorders

Personality Disorder	Symptoms
Cluster A: Odd behaviour
Paranoid	Highly suspicious, untrusting, guarded, hypersensitive, holds grudges.
Schizoid	Isolates self, unable to form emotional attachments; may resemble autism.
Schizotypal	Dresses in unusual ways, lacks social skills, may have odd ideas resembling schizophrenia.
Cluster B: Erratic, overly dramatic behaviour
Narcissistic	Exaggerated self-importance, entitlement, craves admiration, lacks empathy.
Histrionic	Seeks attention and approval, dramatic, self-centred, shallow.
Borderline	Unstable mood, behaviour, self-image, relationships; impulsive, self-harming.
Antisocial	Disregards rights of others, manipulative, impulsive, reckless, lacks remorse.
Cluster C: Anxious, fearful behaviour
Obsessive-compulsive	Concerned with doing things the "right" way, perfectionist, emotionally shallow.
Avoidant	Fears criticism and rejection, avoids social situations.
Dependent	Overly dependent on others for advice and approval, fears abandonment.

Psychotic Disorders

Schizophrenia

• Considered a neurodevelopmental disorder.

• Caused by a combination of genetic, prenatal, and environmental risk factors affecting neuronal connectivity during development.

• Characterized by disordered thinking, perceptions, and delusions.

• In 2024, prevalence in Canada was about 1% (1.16% males, 0.83% females).

• Often diagnosed in adolescence or early adulthood.

Symptoms

• Odd and false belief systems.

• Loss of contact with reality.

• Hallucinations and/or delusions.

• Inappropriate or flat affect.

• Disturbance in thinking.

• Social withdrawal.

• Bizarre behaviour.

• Disorganized speech.

Schizophrenia and the Nervous System

• During adolescence, frontal lobes lose volume due to synaptic pruning; in schizophrenia, excessive pruning leads to fewer connections and less powerful prefrontal cortex.

• Dopamine theory: Excessive dopamine activity and/or other neurotransmitters (norepinephrine, glutamate, serotonin) implicated.

• Low activity levels in frontal lobes.

• Reduced volume in hippocampus, amygdala, thalamus, and frontal lobe grey matter.

Positive and Negative Symptoms

• Positive symptoms: Hallucinations, delusions, thought disturbances, disorganized behaviour, inappropriate affect.

• Negative symptoms: Absent or flat emotional reactions, lack of speech/motivation, loss of normal thoughts/behaviours, flat affect, poorest outcomes.

What Causes Personality Disorders?

Reframing the Situation

• Current research suggests that healthy childhood development was interrupted in some significant manner (e.g., abuse, neglect).

• Old coping mechanisms developed in childhood may become maladaptive in adulthood.

• Personality disorder may be seen as a "badge of courage" for surviving adversity.

Points to Ponder

• Professionals should consider life circumstances, trauma, systemic and structural issues, and culture when assessing personality disorders.

• Trauma-informed practices are increasingly important.

Stigma and Personality Disorders

Impact of Stigma

• Personality disorders are among the most stigmatizing diagnoses, especially in healthcare.

• Stigma affects self-perception and how others treat individuals.

• Structural stigma relates to policies, norms, and practices that limit access to care and well-being.

• Systematic efforts are needed to mitigate stigma-related impacts.

Seven Things to Reduce Stigma

1. Know the facts about mental illness, including substance use disorders.

2. Be aware of your attitudes and behaviour; challenge judgmental thinking.

3. Choose words carefully; language affects attitudes.

4. Educate others; challenge myths and stereotypes.

5. Focus on the positive; mental illness is only part of a person’s life.

6. Support people with dignity and respect.

7. Include everyone; it is illegal to deny jobs or services due to health issues.

Final Thoughts

Resilience and hope are important themes in mental health. As Leonard Cohen said, "There is a crack in everything, that's how the light gets in."