Psychological Disorders – Concise Exam Notes

Definition of Psychological Disorder

• Psychopathology: study of disorders (symptoms, causes, treatment)
• Disorder = atypical, dysfunctional or dangerous thoughts/feelings/behaviors
• APA criteria:
  • Significant disturbances
  • Outside cultural norms
  • Biological/psychological/developmental dysfunction
  • Cause distress/disability

Classification Systems

• DSM-5 (APA): primary U.S. manual; gives diagnostic features, criteria, prevalence, risk factors, comorbidity
• ICD (WHO): global clinical use; broader health monitoring

Key Epidemiology

• Comorbidity common (e.g., OCD + Depression 41\%)
• Lifetime prevalence examples: Anxiety 25-30\%, Specific Phobia 12.5\%, Social Anxiety 12\%, OCD 2.3\%, PTSD 7\%, Major Depression 16.9\%, Bipolar 1\%, Schizophrenia 1\%

Etiological Perspectives

• Supernatural (historical)
• Biological: genetics, neurotransmitters, brain structure
• Psychosocial: learning, cognition, environment
• Diathesis-Stress: predisposition + stress ⇒ disorder

Anxiety Disorders

• Fear = response to imminent threat; Anxiety = apprehension to potential threat
• Specific Phobia: intense fear of object/situation; acquired via classical/vicarious/ verbal learning; evolutionary bias
• Social Anxiety Disorder: fear of negative evaluation; safety behaviors; risk: teasing, behavioral inhibition
• Panic Disorder: recurrent unexpected attacks + worry/behavior change; heritability 43\%; locus coeruleus, catastrophic misinterpretation
• Generalized Anxiety Disorder: excessive worry > 6 months, \ge 3 somatic symptoms; childhood maltreatment link

Obsessive-Compulsive & Related

• OCD: obsessions (intrusive thoughts) and/or compulsions (rituals); genetics (first-degree \times5 risk); serotonin/dopamine/glutamate genes; orbitofrontal hyperactivity; conditioning maintains rituals
• Body Dysmorphic Disorder: preoccupation with imagined defect; repetitive checking/hiding
• Hoarding Disorder: difficulty discarding; clutter impairs living spaces

Post-Traumatic Stress Disorder

• Exposure to trauma; symptoms \ge 1 month: intrusive memories, avoidance, negative mood, hyperarousal
• Risks: interpersonal trauma, low support, subsequent stress, female gender, short serotonin allele
• Learning: trauma cues become conditioned stimuli; cognitive: fragmented memories, negative appraisals

Mood Disorders

• Depressive Disorders: Major Depression (≥ 5 symptoms \ge 2 weeks), Persistent Depressive Disorder, Seasonal, Peripartum
• Bipolar Disorder: mania + depression; early onset (< 25 years); 36\% attempt suicide

Biological Basis of Mood Disorders

• Genetics: Depression twins 50\% (MZ); Bipolar 67\% (MZ)
• Neurotransmitters: serotonin & norepinephrine imbalance; lithium blocks norepinephrine
• Hormones: elevated cortisol activates amygdala, suppresses prefrontal cortex
• Brain: Depression = hyperactive amygdala, hypoactive prefrontal cortex
• Gene-stress: short 5-HTTLPR allele + stress ⇒ depression

Cognitive Theories (Depression)

• Beck: depressive schemas & cognitive biases
• Hopelessness theory: stable/global attributions ⇒ hopelessness ⇒ depression
• Rumination prolongs mood (higher in women)

Suicide

• 90\% linked to mental disorder (mainly mood)
• Male rate \times4 female; firearms vs poison
• Risks: substance abuse, past attempts, lethal means, withdrawal, entrapment, serotonin dysfunction

Schizophrenia

• Positive symptoms: hallucinations, delusions, disorganized thought/behavior
• Negative symptoms: avolition, alogia, asociality, anhedonia
• Causes: genetics (parental risk \times6); dopamine excess (limbic) & deficit (prefrontal); enlarged ventricles, reduced frontal gray; prenatal complications/influenza, birth stress