AP® Psychology review sheet from Aim for Five (aimforfive.com/psych/units/5/5-4)
Unit 5 · Topic 5.4
5.4 Selection of Categories of Psychological Disorders
This topic surveys selected disorders from ten categories, from ADHD and schizophrenia to anxiety, mood, eating and personality disorders. For each, you need the key symptoms and possible causes, which usually combine biological, psychological and social factors. A diagnosis describes a condition a person has, not who they are.
Key terms
- positive and negative symptoms
- major depressive disorder
- bipolar disorder
- generalized anxiety disorder
- obsessive-compulsive disorder
- posttraumatic stress disorder (PTSD)
Before you start, and neurodevelopmental disorders
Use these notes to understand concepts and to match symptoms in fictional exam scenarios, never to diagnose real people. Only trained professionals diagnose. If you or someone you know is struggling, talk to a trusted adult, or call or text 988 to reach the Suicide & Crisis Lifeline in the United States.
Neurodevelopmental disorders begin during the developmental period, and symptoms are judged by whether behavior fits the person's age. In attention-deficit/hyperactivity disorder (ADHD), a person shows ongoing inattention and/or hyperactivity and impulsivity that interfere with functioning in more than one setting. In autism spectrum disorder (ASD), a person has persistent differences in social communication and interaction, along with restricted, repetitive behaviors or interests; 'spectrum' reflects a wide range of support needs. Possible causes are genetic, physiological or environmental. Twin studies show strong genetic influence for both, and extensive research has found that vaccines do not cause autism.
Schizophrenia spectrum disorders
Schizophrenia involves problems in one or more of five areas, and it can be acute (sudden onset, often with better recovery) or chronic (gradual onset and long-lasting). Positive symptoms are the presence of experiences most people don't have; negative symptoms are the absence of typical behaviors.
- Delusions (positive): false beliefs, such as delusions of persecution ('I'm being watched') or grandeur ('I'm a world leader').
- Hallucinations (positive): false perceptions, most often hearing voices, but they can involve any sense.
- Disorganized thinking or speech (positive): for example, word salad, a jumble of words that doesn't make sense.
- Disorganized motor behavior: catatonia can appear as excitement (positive) or stupor, little or no movement (negative).
- Negative symptoms: flat affect (little emotional expression), reduced speech or motivation.
- Possible causes: genetics (risk rises with a closer affected relative), prenatal exposure to viruses, and the dopamine hypothesis, which links symptoms to overactive dopamine signaling.
Mood disorders
Depressive disorders involve a sad, empty or irritable mood with physical and cognitive changes. Major depressive disorder involves depressed mood or loss of interest or pleasure for at least two weeks, with symptoms like changes in sleep and appetite, low energy, trouble concentrating and feelings of worthlessness. Persistent depressive disorder is a long-lasting depressed mood present on most days for at least two years in adults.
Bipolar disorders involve periods of depression and periods of mania, an abnormally elevated or irritable mood with high energy, little need for sleep, racing thoughts and risky behavior. Bipolar I disorder requires at least one full manic episode. Bipolar II disorder involves at least one hypomanic episode (a milder form of mania) and at least one major depressive episode, without full mania. Causes of mood disorders span genetics, neurotransmitters, negative thinking, learned helplessness, stressful events and culture.
Anxiety and obsessive-compulsive disorders
Causes of both groups include learned associations (conditioning), maladaptive thinking, and biological or genetic factors.
| Disorder | Key feature |
|---|---|
| Specific phobia | Intense fear of a particular object or situation, like heights (acrophobia) or spiders (arachnophobia) |
| Agoraphobia | Fear of situations where escape might be hard, like public transportation, open or enclosed spaces, crowds, or being outside the home alone |
| Panic disorder | Repeated, unexpected panic attacks; ataque de nervios is a related culture-bound form seen mainly in people of Latino, especially Caribbean, descent |
| Social anxiety disorder | Intense fear of being watched or judged; taijin kyofusho, seen mainly in Japan, is a fear that one's body offends others |
| Generalized anxiety disorder | Persistent, hard-to-control worry about many things, not one specific trigger |
| Obsessive-compulsive disorder | Obsessions (intrusive, unwanted thoughts) and compulsions (repetitive behaviors done to relieve them), like checking a lock 20 times |
| Hoarding disorder | Persistent difficulty discarding possessions, leading to clutter that disrupts living spaces |
Dissociative, trauma, eating and personality disorders
- Dissociative disorders involve disruptions in memory, identity or awareness, usually linked to trauma or stress. Dissociative amnesia is being unable to recall important personal information; with fugue, the person also travels or wanders away confused about their identity. Dissociative identity disorder involves two or more distinct identity states; researchers debate how it develops.
- Posttraumatic stress disorder (PTSD) follows a traumatic event and includes flashbacks, nightmares, hypervigilance, severe anxiety, insomnia, emotional detachment and hostility, lasting more than a month. Most people who experience trauma don't develop PTSD.
- Anorexia nervosa involves restricting food to a dangerously low body weight, with an intense fear of gaining weight and a distorted body image. Bulimia nervosa involves episodes of binge eating followed by compensating behaviors like vomiting, fasting or excessive exercise; weight is often in the typical range. Causes include genetics, perfectionism and cultural ideals of thinness.
- Personality disorders are enduring, inflexible patterns that differ from cultural expectations, begin by adolescence or early adulthood, and cause distress or impairment. Cluster A (odd or eccentric): paranoid, schizoid, schizotypal. Cluster B (dramatic, emotional or erratic): antisocial, histrionic, narcissistic, borderline. Cluster C (anxious or fearful): avoidant, dependent, obsessive-compulsive.
Worked examples
Try each one yourself first, then open the solution.
- Example 1
The trap: OCD versus obsessive-compulsive personality disorder
In a fictional case, Person A has unwanted thoughts that their family will be harmed and spends two hours a day repeatedly checking locks, knowing it's excessive but feeling unable to stop. Person B insists that every task at work follow strict rules, is rigid about schedules and believes their way is simply the correct way. Which disorder category best matches each description?
Show the solutionHide the solution
- Step 1: Look for true obsessions and compulsions. Person A has intrusive, unwanted thoughts (obsessions) and repetitive checking done to relieve them (compulsions). That matches obsessive-compulsive disorder.
- Step 2: Person B shows a long-standing, pervasive style of perfectionism, rigidity and control, but no intrusive thoughts or rituals. They also see their behavior as right, not as unwanted.
- Step 3: An enduring, inflexible pattern of preoccupation with order and control matches obsessive-compulsive personality disorder, a Cluster C personality disorder.
Answer: Person A's description matches obsessive-compulsive disorder; Person B's matches obsessive-compulsive personality disorder (Cluster C).
- Example 2
Sorting positive and negative symptoms
A fictional case describes a person with schizophrenia who (a) believes a famous singer is sending them secret messages, (b) speaks with almost no facial expression or change in tone, (c) hears a voice commenting on their actions, and (d) stays in one rigid position for hours. Classify each as a positive or negative symptom.
Show the solutionHide the solution
- Step 1: Positive symptoms add experiences most people don't have; negative symptoms take away typical behavior.
- Step 2: (a) A false belief is a delusion, which is positive.
- Step 3: (b) Lack of emotional expression is flat affect, which is negative.
- Step 4: (c) Hearing a voice that isn't there is a hallucination, which is positive.
- Step 5: (d) Lack of movement is catatonic stupor, which is negative.
Answer: (a) positive, (b) negative, (c) positive, (d) negative.
Common mistakes
- Reading 'positive' symptoms as good. Positive means something is added (like hallucinations); negative means something is missing (like flat affect).
- Mixing up bipolar I and II. Bipolar I requires full mania; bipolar II involves hypomania plus major depression.
- Confusing OCD with obsessive-compulsive personality disorder. OCD involves intrusive obsessions and compulsions; the personality disorder is a rigid, lasting style of perfectionism and control.
- Assuming dissociative identity disorder and schizophrenia are the same. Schizophrenia involves psychosis like delusions and hallucinations, not separate identity states.
On the exam
- Most questions describe a fictional person's symptoms and ask which disorder or category they best match. Look for the one detail that separates similar options, like duration, mania versus hypomania, or one fear versus many worries.
- When asked for a possible cause, name a specific factor and its perspective, such as 'a genetic vulnerability (biological)' or 'negative automatic thoughts (cognitive).'
Connected topics
Videos
Check yourself
4 questions on 5.4 Selection of Categories of Psychological Disorders. Pick an answer to see if you got it, and why.
A clinician learns that a client recently went a week sleeping only a few hours a night without feeling tired, talked rapidly, started several major projects at once and spent most of his savings in a few days. Months earlier, he had a long period of deep sadness and loss of interest. Which diagnosis is most consistent with this pattern?
A client tells a clinician that she has constant, unwanted thoughts that her hands are contaminated with germs. She washes her hands dozens of times a day, which briefly eases her anxiety, and her skin has become cracked and sore. Which diagnosis is most consistent with these symptoms?
Four months after being in a serious fire, a client tells a clinician that she has frequent nightmares and sudden, vivid memories of the fire, avoids anything that reminds her of it, feels constantly on edge and startles easily. Which diagnosis is most consistent with these symptoms?
A teacher and parents notice that, since early childhood, a 9-year-old has had ongoing trouble staying focused, often fidgets and interrupts, and these difficulties show up both at home and at school. A clinician evaluating the child would most likely consider a disorder from which category?
0 of 4 answered