Priming Questions

1. A 23-year-old with hallucinations and social decline for 8 months. What’s the most likely diagnosis?
2. A man disappears after trauma, later found living under a new name with no memory of his past. What disorder does this suggest?
3. A student feels detached, like he’s outside his body, but knows it isn’t real. What condition fits best?
4. A woman has seizure-like episodes with eyes closed and a normal EEG. What’s the most likely diagnosis?

Schizophrenia Spectrum

Definition/Overview

• Disorders of distorted perception, thought, and behavior
• Core symptoms: delusions, hallucinations, disorganized speech/behavior, negative symptoms
• Exist along a time + mood spectrum

Clinical Presentation

• Positive symptoms: hallucinations (auditory > visual), delusions (persecutory, grandiose), disorganized speech/behavior
• Negative symptoms: flat affect, anhedonia, avolition, alogia, social withdrawal
• Cognitive: impaired attention, executive function
• Onset: late teens to mid-30s; earlier in men

Spectrum Breakdown (time + mood = key)

• Brief psychotic disorder

  • Duration: <1 month
  • Sudden onset, often stress-related
  • Full recovery is common

• Schizophreniform

  • Duration: 1–6 months
  • Same symptoms as schizophrenia
  • No functional decline required
  • ~⅓ recover, ~⅔ progress to schizophrenia or schizoaffective

• Schizophrenia

  • Duration: ≥6 months (≥1 month active symptoms)
  • Requires functional decline (social/occupational)
  • Positive + negative symptoms
  • Chronic, worse prognosis

• Schizoaffective disorder

  • Meets schizophrenia criteria + mood disorder (major depression or mania)
  • ≥2 weeks psychosis without mood symptoms
  • If psychosis only during mood episode → mood disorder with psychotic features (not schizoaffective)

• Delusional disorder

  • ≥1 month fixed delusion
  • Functioning not markedly impaired
  • No other psychotic features

Labs, Studies, and Physical Exam Findings

• Clinical diagnosis (DSM-5 criteria)
• Labs/imaging to rule out medical/substance causes: CBC, CMP, TSH, urine tox, neuroimaging if focal neuro deficits

Treatment

• First-line: atypical antipsychotics (risperidone, olanzapine, quetiapine, aripiprazole, ziprasidone)
• Acute agitation: haloperidol, lorazepam
• Clozapine: treatment-resistant schizophrenia (monitor CBC → agranulocytosis risk)
• Psychosocial: CBT, social skills, family therapy
• Hospitalization if danger to self/others

Schizophrenia Spectrum Timeline

Key Differentiators

• Brief psychotic disorder vs Schizophreniform → <1 mo vs 1–6 mo
• Schizophreniform vs Schizophrenia → no functional decline vs functional decline
• Schizophrenia vs Schizoaffective → schizoaffective has mood episodes, but ≥2 weeks psychosis without mood
• Schizophrenia vs Delusional disorder → broad psychotic symptoms + decline vs single delusion with preserved function

Test Alert

• Duration is the #1 clue on exams: <1 mo = brief, 1–6 mo = schizophreniform, ≥6 mo = schizophrenia
• Functional decline must be present for schizophrenia diagnosis
• Psychosis occurring only during a mood episode = mood disorder w/ psychotic features, not schizoaffective
• Clozapine is reserved for treatment-resistant schizophrenia (monitor CBC for agranulocytosis)

Dissociative Disorders

Definition/Overview

• Disruption in consciousness, memory, identity, or perception
• Often follows trauma or severe stress
• Main types: Dissociative identity disorder, dissociative amnesia (with or without fugue), depersonalization/derealization disorder

Clinical Presentation

Dissociative Identity Disorder

• Two or more distinct identities or personality states
• Gaps in memory (amnesia for everyday events, trauma, or personal information)
• Often linked to severe, repeated childhood trauma
• Think: patient “loses time,” finds items they do not remember buying, others notice voice or posture changes
• Not schizophrenia → no hallucinations or delusions as core features, instead switching identities

Dissociative Amnesia

• Inability to recall important personal information, usually trauma or stress related
• Too extensive to be ordinary forgetting
• Patient is aware they cannot remember (distress, frustration)
• Dissociative fugue subtype → amnesia with sudden travel or wandering, may assume a new identity
• Example: person disappears after trauma, later found in another town with no memory of prior life

Depersonalization/Derealization Disorder

• Depersonalization = detachment from self (“I feel like I am outside my body, watching myself”)
• Derealization = detachment from surroundings (“the world feels unreal, dreamlike, foggy”)
• Reality testing remains intact → they know it is a feeling, not a delusion
• Example: patient says, “I know I am real, but I feel like I am in a movie.”

Labs, Studies, and Physical Exam Findings

• Clinical diagnosis
• Must rule out seizures, head injury, intoxication or withdrawal, and medication effects
• Mental status exam may show memory gaps, identity changes, and intact orientation or reality testing in depersonalization/derealization disorder

Treatment

• First-line: psychotherapy (trauma-focused therapy, cognitive behavioral therapy, eye movement desensitization and reprocessing, supportive therapy)
• Medications: no specific drug treatment; address comorbid depression, anxiety, or post-traumatic stress disorder
• Hospitalization if risk to safety

Key Differentiators

• Dissociative identity disorder vs Schizophrenia → multiple identities and memory gaps vs hallucinations and delusions
• Dissociative amnesia vs Normal forgetting → trauma-related, too extensive, inconsistent with ordinary memory loss
• Depersonalization/derealization disorder vs Psychosis → detachment feelings with insight vs loss of reality testing

Test Alert

• Dissociative identity disorder is strongly linked to severe childhood trauma
• Dissociative fugue = amnesia with travel
• Depersonalization/derealization disorder = patients recognize the experience is unreal

Psychogenic Nonepileptic Seizure

Definition/Overview

• Episodes that resemble epileptic seizures but occur without abnormal electrical brain activity
• Classified as a functional neurological symptom disorder (conversion disorder)
• Caused by psychological factors, often stress, trauma, or psychiatric comorbidity

Clinical Presentation

• Convulsive-like episodes with features atypical for epilepsy:
  • Asynchronous or thrashing limb movements
  • Eyes closed during episode (in true seizures, eyes are usually open)
  • Prolonged duration, fluctuating course
  • Lack of postictal confusion
• Often occur in stressful situations or in the presence of others
• Strong association with history of trauma, abuse, depression, anxiety, or dissociation

Labs, Studies, and Physical Exam Findings

• Gold standard: Video electroencephalogram (EEG) monitoring during an event → shows normal brain activity despite convulsions
• Routine labs and imaging normal
• Important clinical point: may coexist with true epilepsy, so both must be considered

Treatment

• First-line: psychotherapy (cognitive behavioral therapy, trauma-focused therapy, supportive therapy)
• Treat comorbid psychiatric conditions such as depression, anxiety, or post-traumatic stress disorder
• Avoid unnecessary antiepileptic drugs (ineffective and potentially harmful)
• Best managed with collaboration between neurology and psychiatry/psychology

Key Differentiators

• Psychogenic nonepileptic seizure vs Epileptic seizure → normal EEG during event in psychogenic nonepileptic seizure
• Psychogenic nonepileptic seizure vs Syncope → psychogenic nonepileptic seizure has prolonged, irregular movements; syncope is brief with sudden loss of tone
• Psychogenic nonepileptic seizure vs Panic attack → psychogenic nonepileptic seizure = seizure-like motor activity; panic attack = autonomic symptoms (palpitations, sweating, tremor, shortness of breath)

Test Alert

• Diagnosis requires video EEG with no epileptiform activity
• Do not use antiepileptic medications unless epilepsy is proven
• Strong association with psychological stress and trauma