Major Psychological Disorders to Know for AP Psychology

1. What You Need to Know

Psychological disorders on AP Psych are tested as clusters of symptoms + typical patterns (thoughts, feelings, behaviors) that cause distress and/or impairment. You’re expected to recognize disorders from short scenarios, distinguish similar ones, and use the DSM framework (not to “diagnose,” but to classify).

Core ideas AP Psych expects

  • DSM-5(-TR): the main classification system (lists criteria for disorders). AP questions often mirror DSM-style symptom lists.
  • Four D’s (quick abnormality screen): Deviance, Distress, Dysfunction, Danger (not an official DSM rule, but a common AP tool).
  • Biopsychosocial approach: disorders usually involve biological (genes, brain, neurotransmitters), psychological (cognition, learning, emotion), and social (stress, culture) factors.
  • Diathesis–stress model: a vulnerability (diathesis) + stress can trigger a disorder.
  • Comorbidity: disorders often co-occur (e.g., depression + anxiety).

Reminder for FRQs/ethics: You describe patterns and criteria; you don’t claim you can clinically diagnose a real person from one behavior.

2. Step-by-Step Breakdown

AP questions are usually “identify the disorder” or “which feature best supports diagnosis?” Use this fast decision process.

A. Step-by-step: Identify a disorder from a vignette

  1. Name the symptom type first
    • Anxiety/fear? Mood change? Psychosis? Personality pattern? Eating/weight? Trauma? Neurodevelopment?
  2. Check duration + triggers (AP loves this)
    • Panic attacks: minutes; panic disorder needs ongoing worry/behavior change.
    • MDD: at least 2 weeks.
    • Mania: about 1 week (or hospitalization).
    • PTSD: more than 1 month; acute stress disorder: 3 days–1 month.
  3. Look for the “signature” symptom
    • OCD: intrusive obsessions + repetitive compulsions.
    • Schizophrenia: delusions/hallucinations + disorganization/negative symptoms.
    • Bipolar I: manic episode.
    • Anorexia: restriction + significantly low weight + fear of gaining.
  4. Rule out common confusions
    • DID vs schizophrenia (identity states vs hallucinations/delusions).
    • OCD vs OCPD (anxiety-driven rituals vs perfectionistic personality style).
    • GAD vs panic disorder (chronic worry vs unexpected attacks).
    • Bipolar vs “moodiness” (mania/hypomania are distinct syndromes).
  5. Choose the best match and justify with 2–3 concrete details
    • On MCQ/FRQ, your points come from specific symptoms (“recurrent unexpected panic attacks,” “compulsions consume hours,” “grandiosity + decreased need for sleep”).

B. Micro-example of the method

  • Vignette: “For 8 months, Sam worries daily about school, family health, and money; feels restless, irritable, and has trouble sleeping.”
    • Symptom type: anxiety/worry; Duration: 8 months; Signature: excessive worry across domains.
    • Answer: Generalized Anxiety Disorder (GAD).

3. Key Formulas, Rules & Facts

(No math here—just high-yield rules.)

A. Big diagnostic “buckets” (what AP focuses on)

CategoryKey ideaHigh-yield disorders to knowQuick ID clues
Anxiety DisordersFear/anxiety out of proportionGAD, Panic Disorder, Phobias, Social Anxiety, AgoraphobiaAvoidance, physical arousal, persistent worry
OCD & RelatedObsessions/compulsions or related repetitive behaviorsOCD, Hoarding, Body Dysmorphic, TrichotillomaniaTime-consuming rituals or fixation on perceived flaws
Trauma/Stressor-RelatedSymptoms after trauma/stressorPTSD, Acute Stress DisorderIntrusions/flashbacks + avoidance + hyperarousal
Depressive DisordersLow mood/anhedoniaMajor Depressive Disorder2+ weeks, vegetative symptoms, impaired functioning
Bipolar DisordersMania/hypomania + mood shiftsBipolar I, Bipolar IIManic energy, decreased sleep, risky behavior
Schizophrenia SpectrumPsychosis + impairmentSchizophrenia (also brief psychotic, schizophreniform)Delusions/hallucinations + disorganization + negative symptoms
Dissociative DisordersDisruption of identity/memoryDissociative Identity Disorder, Dissociative AmnesiaIdentity states, memory gaps, depersonalization
Somatic Symptom & RelatedDistressing bodily symptoms + excessive focusSomatic Symptom Disorder, Illness Anxiety, Conversion DisorderMedical explanation absent/insufficient; high health anxiety
Personality DisordersInflexible, enduring maladaptive traitsAntisocial, Borderline, Narcissistic (plus clusters)Long-term pattern across contexts
Eating DisordersDisturbed eating/weight controlAnorexia, Bulimia, Binge-Eating DisorderRestriction vs binge/purge vs binge-only
NeurodevelopmentalEarly-onset developmental patternsADHD, Autism Spectrum DisorderChildhood onset; school/social functioning
NeurocognitiveDecline from prior functioningMajor neurocognitive disorder (e.g., Alzheimer’s)Progressive memory/cognitive decline
Substance-RelatedProblematic use + impairmentSubstance Use DisorderTolerance/withdrawal + life disruption

B. Anxiety disorders (recognition facts)

DisorderDefining featuresWhat to listen for in vignettes
GADExcessive worry most days about many things; hard to control; physical tension“Worries about everything,” restless, muscle tension, sleep issues
Panic DisorderRecurrent unexpected panic attacks + ongoing concern/avoidance“Out of nowhere,” sudden terror + heart racing + fear of dying/losing control
Specific PhobiaIntense fear of a specific object/situation; avoidanceHeights, spiders, needles; immediate fear response
Social Anxiety DisorderFear of negative evaluation/social scrutinyAvoids presentations, parties; fear of embarrassment
AgoraphobiaFear/avoidance of places where escape is hardAvoids crowds, buses, malls; may stay home

C. OCD and related

DisorderCore conceptTypical trap
OCDObsessions (intrusive thoughts) + compulsions (rituals) to reduce anxietyIt’s not “liking neatness”; it’s distressing + time-consuming
Hoarding DisorderPersistent difficulty discarding itemsNot just clutter—impairs living spaces
Body Dysmorphic DisorderPreoccupation with perceived appearance flawCan resemble eating disorders but focus is “defect”

D. Trauma/stressor-related

DisorderKey timingKey symptom clusters
Acute Stress Disorder3 days–1 month after traumaIntrusion, negative mood, dissociation, avoidance, arousal
PTSDMore than 1 monthIntrusions/flashbacks, avoidance, negative mood/cognitions, hyperarousal

E. Mood disorders (depression + bipolar)

DisorderSignatureHigh-yield notes
Major Depressive Disorder (MDD)At least 2 weeks of depressed mood and/or anhedonia + other symptomsSymptoms can include sleep/appetite change, fatigue, worthlessness, concentration issues, suicidal ideation
Bipolar IManic episode (may also have depression)Mania can include grandiosity, decreased need for sleep, pressured speech, risky behavior
Bipolar IIHypomanic episode + major depressive episode (no full mania)Hypomania is less severe than mania, but still a noticeable change

F. Schizophrenia spectrum (AP’s key features)

ConceptWhat it meansExamples
Positive symptoms“Added” experiencesDelusions, hallucinations, disorganized speech/behavior
Negative symptoms“Subtracted” functioningFlat affect, reduced speech (alogia), avolition, social withdrawal
Delusion vs hallucinationFalse belief vs false perception“CIA is tracking me” vs hearing voices

Quick timeline distinctions (often tested):

  • Brief psychotic disorder: psychosis lasting less than 1 month.
  • Schizophreniform: 1–6 months.
  • Schizophrenia: signs of disturbance for 6+ months (with major impairment).

G. Dissociative vs somatic symptom disorders

DisorderCore featureVignette clue
Dissociative Identity Disorder (DID)2+ identity states + memory gaps“Different selves,” amnesia for actions, trauma history possible
Dissociative AmnesiaInability to recall important autobiographical info“Can’t remember” key events; may involve fugue
Depersonalization/DerealizationFeeling detached from self/world“I feel unreal,” “like I’m watching myself”
Somatic Symptom DisorderDistressing somatic symptoms + excessive thoughts/behaviorsRepeated doctor visits; high distress
Illness Anxiety DisorderPreoccupation with having illness with minimal symptoms“Convinced I have cancer” despite reassurance
Conversion Disorder (Functional Neurological)Neurological symptoms incompatible with medical findingsParalysis, blindness, seizures without neurological basis

H. Personality disorders (AP emphasis)

Personality disorders are enduring, inflexible, and show up across situations.

ClusterThemeExamples
A (odd/eccentric)suspicious/withdrawnParanoid, Schizoid, Schizotypal
B (dramatic/erratic)impulsive/emotionalAntisocial, Borderline, Histrionic, Narcissistic
C (anxious/fearful)anxious/avoidantAvoidant, Dependent, OCPD

High-yield individual ones:

  • Antisocial PD: disregard for others’ rights, deceit, impulsivity, lack of remorse (pattern; often history of conduct problems).
  • Borderline PD: instability in relationships/self-image/emotions + impulsivity; fear of abandonment; self-harm may appear.
  • Narcissistic PD: grandiosity, need admiration, lack of empathy.

I. Eating disorders (don’t mix them up)

DisorderDefining patternKey distinction
Anorexia NervosaRestriction leading to significantly low weight + intense fear of gainingLow weight is central; may overexercise
Bulimia NervosaBinge eating + compensatory behaviors (vomiting, laxatives, excessive exercise)Weight may be normal range
Binge-Eating DisorderBinges without compensatory behaviorsDistress about binges; often weight gain

J. Neurodevelopmental + neurocognitive + substance

DisorderCore ideaVignette clue
ADHDInattention and/or hyperactivity-impulsivity across settings, childhood onsetSchool trouble, distractibility, fidgeting, blurting
Autism Spectrum Disorder (ASD)Social communication deficits + restricted/repetitive behaviorsLimited reciprocity, fixated interests, sensory sensitivities
Major Neurocognitive Disorder (e.g., Alzheimer’s)Significant cognitive declineProgressive memory loss + impaired daily functioning
Substance Use DisorderProblematic use causing impairment/distressFailed attempts to cut down, tolerance/withdrawal, neglect roles

4. Examples & Applications

Example 1: Panic disorder vs GAD

  • Vignette: “Jordan has sudden episodes of terror with chest tightness and dizziness; now avoids the gym because he fears it will happen again.”
  • Key insight: Unexpected panic attacks + avoidance/worry afterwardPanic Disorder (not just general worry).

Example 2: PTSD vs Acute Stress Disorder

  • Vignette: “Two weeks after a car crash, Mei has nightmares, feels numb, avoids driving, and startles easily.”
  • Key insight: Trauma symptoms within 3 days–1 monthAcute Stress Disorder (PTSD requires more than 1 month).

Example 3: Schizophrenia vs DID

  • Vignette A: “Luis believes neighbors planted cameras in his walls and hears voices commenting on him.” → Schizophrenia spectrum (delusions + hallucinations).
  • Vignette B: “Ava finds clothes she doesn’t remember buying and is told she acted like a different person.” → DID (identity states + amnesia), not schizophrenia.

Example 4: Anorexia vs Bulimia

  • Vignette: “Priya restricts food intensely, is significantly underweight, and still fears ‘getting fat.’” → Anorexia Nervosa.
  • Vignette: “Chris binges secretly then vomits and feels ashamed; weight is near average.” → Bulimia Nervosa.

5. Common Mistakes & Traps

  1. Mixing up delusions and hallucinations

    • Wrong: calling a false belief a hallucination.
    • Fix: Delusion = belief; hallucination = perception (hearing/seeing/feeling things).
  2. Assuming OCD is just being neat/organized

    • Wrong: equating OCD with perfectionism.
    • Fix: OCD involves intrusive distressing thoughts + compulsions to reduce anxiety; it’s time-consuming/impairing.
  3. Confusing schizophrenia with DID

    • Wrong: “multiple personalities” = schizophrenia.
    • Fix: schizophrenia = psychosis (delusions/hallucinations); DID = identity disruption + amnesia.
  4. Calling any anxiety a panic disorder

    • Wrong: labeling chronic worry as panic.
    • Fix: panic disorder requires recurrent unexpected panic attacks plus persistent concern/behavior change.
  5. Overcalling bipolar disorder

    • Wrong: “mood swings” = bipolar.
    • Fix: bipolar requires mania/hypomania syndrome (decreased need for sleep, grandiosity, pressured speech, risky behavior). Irritability alone isn’t enough.
  6. Forgetting PTSD timing

    • Wrong: diagnosing PTSD at 2 weeks post-trauma.
    • Fix: Acute stress is 3 days–1 month; PTSD is more than 1 month.
  7. Mixing up anorexia and bulimia

    • Wrong: thinking bulimia always means underweight.
    • Fix: Anorexia = significantly low weight from restriction; bulimia = binge + compensatory behaviors (often normal-range weight).
  8. Treating personality disorders like short episodes

    • Wrong: describing a brief phase as borderline/antisocial.
    • Fix: personality disorders are enduring patterns across time and contexts.

6. Memory Aids & Quick Tricks

Trick / MnemonicHelps you rememberWhen to use it
Four D’s: Deviance, Distress, Dysfunction, DangerQuick abnormality screenWhen asked what makes behavior “disordered”
D = Delusion (belief) / H = Hallucination (hearing/seeing)Psychosis vocabularySchizophrenia-spectrum questions
PTSD = Post = “Past 1 month”PTSD timing thresholdPTSD vs acute stress
BiPolar I = “I = Intense” (full mania)Bipolar I has maniaBipolar I vs II
Bipolar II = “Two parts”: hypomania + depressionBipolar II structureBipolar classification
Anorexia = “A” for Absent weightLow weight is centralEating disorder ID
Bulimia = “Binge + Bathroom”Binge then purge/compensateBulimia vs binge-eating
Cluster B = “Bad Boundaries/Behavior”Dramatic/erratic PDsPersonality disorder clusters

7. Quick Review Checklist

  • You can quickly sort a vignette into: anxiety, mood, psychosis, trauma, personality, eating, dissociative/somatic, neurodevelopmental, substance, neurocognitive.
  • You know the signature pairs:
    • OCD = obsessions + compulsions
    • Panic disorder = unexpected attacks + persistent worry/avoidance
    • MDD = 2+ weeks depressed mood/anhedonia
    • Bipolar I = mania; Bipolar II = hypomania + depression
    • PTSD = trauma symptoms lasting more than 1 month
    • Schizophrenia = psychosis + impairment (positive/negative symptoms)
  • You won’t mix up:
    • Delusions vs hallucinations
    • Schizophrenia vs DID
    • Anorexia vs bulimia vs binge-eating
  • You can name at least one key symptom and one distinguishing clue for each major disorder above.

You’ve got this—if you anchor on the “signature symptom + timing,” most AP disorder questions collapse into an easy match.