Chapter 13: Psychological Disorders

Intro to Psychology

Diagnosing Mental Disorders

  • Mental disorder: a harmful disfunction.
    • Harmful to oneself or others.
    • Dysfunctional because it is not performing its evolutionary function.
  • Mental disorder (another definition): a disturbance in thinking, emotion, or behavior that causes a person to suffer, is self-destructive, seriously impairs a person’s ability to work or get along with others, or makes a person unable to control the impulse to endanger others.
    • By this definition, many people will have some mental health problem in the course of their lives.
  • DSM: Diagnostic and Statistical Manual of Mental Disorders, published by American Psychiatric Association.
    • Lists symptoms, etc, sex ratio of those affected, etc.
    • What is included in this book affects who gets covered by insurance or which children get individualized educational plans.
    • Problems:
      • Adding labels may encourage clinicians to diagnose that more (e.g. ADHD).
      • Once a person is diagnosed, other people may see everything they do through that lens.
      • Many diagnoses continue to stem from cultural biases (e.g. relating to menstruation, homosexuality).
  • Culture shapes particular symptoms that stem from a disorder.
  • Methods of diagnosis:
    • Self-report questionnaires
    • Projective tests
      • Ambiguous pictures, sentences, or stories that the test taker interprets or completes.
      • Many of these tests lack reliability (they are interpreted by the clinician) and validity (results can vary depending on sleepiness, hunger, medication, etc).
      • Can allow children to express things that they’d otherwise not express.


  • Categorical perspective: you either have a disorder or you don’t.
    • Problems:
      • Symptoms below threshold can still be impairing, but are not recognized as a diagnosis
      • Signs and symptoms don’t always fit neatly into one diagnosis
  • Dimensional perspective: people’s disorders are on a spectrum and can change day-to-day.
  • Synonymous terms: mental illness, emotional disorders, mental disorders, psychiatric disorders, psychological disorders
    • Not synonymous: “Insanity”
      • Legal term (= person cannot distinguish reality from fantasy)
  • Symptoms: reported by patient
  • Signs: observable by other people
  • Syndrome: a collection of signs and symptoms that go together and characterize a disorder or condition
  • Diagnosis: the process of seeing whether signs and symptoms identify a disorder
  • Things that are not disorders:
    • An expected or culturally approved response to a common stressor (e.g. death of a loved one)
    • Deviant behavior

Depressive and Bipolar Disorders

  • Major depression: a disorder involving disturbances in emotion, behavior, cognition, and body function.
    • 20% of people will experience it sometime in their lives.
    • 2x more common in women.
      • Could be a biological difference; could be that men report it less.
    • Depressed mood for most of the day for 2+ weeks
    • Feelings of excessive guilt or worthlessness
    • Difficulty concentrating, indecisiveness
    • Suicidal thinking, plans, or behaviors
  • Bipolar disorder: going back and forth between mania and depression.
    • In a manic state, people feel powerful and overconfident in their plans.
  • Vulnerability-stress model: psychological disorders are a combination of stress and your vulnerability to it (genetic predisposition, personality traits, habits of thinking, violence and abuse, loss of important relationships).
    • Studied with twin studies to isolate genes and environment.
      • For genetic disorders, concordance should be high (consistency in disorder between twins).
  • Monoamine hypothesis
    • Not enough serotonin and norepinephrine in the synapses
  • Brain structure and function
    • Decreased gray matter

Anxiety Disorders

  • Generalized anxiety disorder: uncontrollable anxiety or worry — a feeling of foreboding and dread.
    • Can be caused by stress and genetic predisposition (abnormalities in the amygdala or prefrontal cortex), consistent with vulnerability-stress model.
  • Panic disorder: person has recurring panic attacks.
    • Can be triggered by stressful events, or occur delayed after the scare.
    • Most people see panic attacks as a passing stress, but people with panic disorder regard the panic attack as a sign of illness or impending death, which causes them to also try to avoid future panic attacks.
    • Fear network (amygdala, etc) is hypersensitive.
    • Frontal Cortex fails to inhibit fear network.
  • Social anxiety disorder (social phobia): person becomes extremely anxious in situations where they will be observed by others.
    • Fear of negative evaluation.
    • Lifetime prevalence: 3-13%
    • Increased amygdala activation
  • Agoraphobia: person fears places where escape or rescue might be difficult in the event of a panic attack.
    • Often begins with a panic attack with seemingly no cause. The person avoids situations that they think may provoke another one.

Specific Phobia

  • Fear and avoidance must significantly impact life for 6+ months.
  • Lifetime prevalence: 7-9%
  • Increased amygdala activation
  • Blood-injury phobias are different than other phobias
    • Bi-phasic response
      • Heart rate and blood pressure go up rapidly (like other phobias), but then they drop rapidly
      • This triggers fainting

Trauma and Obsessive-Compulsive Disorders

  • PTSD: trauma symptoms persist for one month or longer and begin to impair functioning.
  • Vulnerability-stress model predicts that only some people who experience the same traumatizing events will develop PTSD depending on their vulnerability.
    • Some PTSD sufferers have a smaller hippocampus, making it difficult for them to react to their memories as events from the past.
    • Prior history of psychological problems can also increase vulnerability.
    • Lower IQ may increase vulnerability.
  • OCD: recurrent, persistent, unwanted thoughts or images.
    • Obsessions and compulsions become a disorder only when they cause distress and interfere with a person’s life.
    • Often: hand-washing, counting, touching, and checking.
    • The sufferer feels like they’re in a constant state of danger and repeatedly tries to reduce the resulting anxiety.
    • Caused by caudate in brain not filtering impulses.
  • Hoarding disorder is categorized in the DSM-5 as a subcategory of OCD.

Personality Disorders

  • Borderline personality disorder: people with extremely negative emotionality and who are unable to regulate their emotions.
    • They try to avoid real or imagined abandonment.
    • Emotionally volatile.
    • Many of these people deliberately injure themselves in acts of cutting and self-mutilation.
    • Biosocial model: a child is born with a genetic vulnerability that produces abnormalities in the frontal lobes and brain areas involved in emotion and a disposition towards negative emotionality. The child behaves impulsively, which is worsened by an “invalidating environment” created by their parents. The parents tell them to cope alone, but reinforce the outbursts with attention. These mixed messages cause the child to not learn how to understand and label feelings or how to regulate them.
  • Antisocial personality disorder (APD): reckless people who break the law and violate the rights of others; are impulsive and seek quick thrills.
    • Seems to have a genetic basis, but also environmental influences (i.e. non-loving parents, abuse).
    • People with APD have less activation in the frontal lobe (behavior inhibition).
    • People with APD may have smaller amygdala volumes.
  • Psychopathy: heartless, unable to feel normal emotions (psychopaths).
    • Psychopaths may be more prevalent in individualistic Western societies.
    • Most psychopaths do not respond physiologically to the threat of punishment.
    • Lesser ability to empathize, feel fear, or “get” fear in others.

Addictive Disorders

  • Biological model:
    • Addiction is mostly due to a person’s neurology and genetic predisposition.
    • Some people are particularly vulnerability to addiction.
    • People whose genes make them less sensitive to alcohol (they have to drink more to feel it) are at a higher risk of developing alcoholism.
      • This may explain why Asians (who experience “Asian flush”) have lower rates of alcoholism.
    • Addictions can change a person’s biology.
      • This causes addictive behavior to feel automatic.
  • Learning model:
    • The environment can encourage or discourage factors involved in addiction. 1. Cultural practices 2. Policies of total abstinence tends to increase rates of addiction 3. Not all addicts have withdrawal symptoms when they stop using a drug - The environment where the drug is taken effects the drug’s physiological effects. 4. Addiction also depends on the reasons for taking a drug (motives matter)

Dissociative Identity Disorder

  • Dissociative identity disorder (DID): the emergence, within one person, of two or more distinct personalities.
    • Separate names, memories, and personalities.
    • May originate in childhood as a way of coping with abuse.
    • “Dissociative amnesia” (repressing trauma and developing several identities as a result) lacks empirical support.
      • People generally have trouble forgetting traumatic events.
    • DID may be a culture-bound syndrome, generated by clinicians and people opening clinics to treat it (it became lucrative business).
      • It was relatively rare until it exploded in media attention.


  • Schizophrenia: the personality loses its unity.
    • Words separated from meaning, actions from motives, perceptions from reality.
    • Example of psychosis, a condition that involves distorted perceptions of reality and irrational behavior.
    • Five core abnormalities:
      1. Delusions (people plotting against them, etc)
      2. Hallucinations (most common is hearing voices)
      3. Disorganized speech
      4. Grossly disorganized or catatonic behavior
      5. Negative symptoms (losing the motivation to take care of themselves or interact with others; negative = absence of normal behaviors)
    • 40% of people with schizophrenia have one or more periods of recovery.
  • Lifetime prevalence: 1%
  • Peak age of onset: early 20s
  • Sex ratio 1:1, but men have more cognitive impairment and worse symptoms
  • Schizophrenia involves less gray matter in the prefrontal cortex and temporal lobes, abnormalities in the hippocampus, abnormalities in neurotransmitters, etc.
  • Three contributing factors to schizophrenia:
    1. Genetic predispositions (highly heritable)
    2. Prenatal problems or birth complications (damages to fetal brain)
    3. Biological events during adolescence (too many synapses pruned away)
  • Positive symptoms (excess):
    • Hallucinations (auditory)
    • Delusions
    • Disorganized speech
      • Loosening of associations
      • Incoherence
  • Negative symptoms
    • Flat affect (unfazed facial expression)
    • Alogia (not speaking much, no motivation to talk)
    • Avolition (no motivation)
    • Social/occupational dysfunction
  • Dopamine hypothesis
    • Excessive dopamine gives rise to positive symptoms