Neurology, Psychiatry and Special Senses on USMLE Step 1

Scope and time budget

Thirty-four questions is more than one full 30-minute block on the current format. The row has 20 subtopics, so it deserves around two weeks in a 12-week plan. Split the time between neuroscience (anatomy, pathways, stroke, degenerative and demyelinating diseases, seizures) and behavioral health (mood, psychosis, anxiety, substance use, personality, eating and sleep disorders, neurodevelopment). The neuroscience half needs diagrams, and the psychiatry half needs drug tables and diagnostic criteria. The two halves meet in neuropharmacology.

What is tested

• Cortex and deep structures. Cortical localization, aphasias and neglect, basal ganglia and movement disorders, cerebellum and brainstem lesion syndromes.
• Tracts and nerves. Cranial nerves, spinal cord tracts and lesion syndromes.
• Vascular and structural disease. Stroke syndromes and cerebral blood supply, CNS tumors, intracranial hemorrhage and increased intracranial pressure.
• Medical neurology. Seizures and antiepileptic drugs, neurodegenerative diseases, demyelinating and neuromuscular diseases, and CNS infections.
• Neuropharmacology. Anesthetics, opioids and sedative-hypnotics.
• Special senses. Visual pathways, glaucoma and retinal disease, hearing and vestibular disorders.
• Psychiatry. Mood disorders and their drugs, psychotic disorders and antipsychotics, anxiety and trauma-related disorders, substance use disorders, personality, eating, sleep and somatic symptom disorders, and neurodevelopmental and child psychiatric disorders.

Anchor facts and US conventions

• Aphasias. Broca area (inferior frontal gyrus) lesion gives nonfluent aphasia with intact comprehension. Wernicke area (superior temporal gyrus) lesion gives fluent aphasia with poor comprehension.
• Stroke territories. Middle cerebral artery: contralateral face and arm weakness greater than leg, with aphasia in the dominant hemisphere or neglect in the nondominant hemisphere. Anterior cerebral artery: contralateral leg weakness. Posterior cerebral artery: contralateral homonymous hemianopia.
• Parkinson disease. Loss of dopaminergic neurons in the substantia nigra pars compacta, with resting tremor, rigidity and bradykinesia. Levodopa with carbidopa is the standard pairing.
• Psychiatric drugs. SSRIs are first-line for major depression and many anxiety disorders, with serotonin syndrome risk when combined with MAO inhibitors. Lithium treats bipolar disorder and needs monitoring of levels, thyroid and renal function, and it carries a risk of Ebstein anomaly in pregnancy. Atypical antipsychotics cause metabolic syndrome.
• Alcohol withdrawal. Onset 6-24 hours after the last drink, with delirium tremens at 48-96 hours. Benzodiazepines are the treatment. Give thiamine before glucose to prevent Wernicke encephalopathy.
• Antidotes and overdose. Naloxone for opioids and flumazenil for benzodiazepines, with the caution that flumazenil can precipitate seizures in dependent patients.
• US conventions. Psychiatric diagnoses follow DSM criteria as taught in US curricula, and drug names are US generics. Use the exam's reference list for laboratory values such as sodium, glucose and drug levels.

Three typical traps

1. Reading deficits on the wrong side. Most cortical tracts cross, and several brainstem lesions produce crossed findings (ipsilateral cranial nerve signs with contralateral body signs). Draw the lesion and the tract before you choose, and state out loud which side the deficit is on.
2. Confusing similar drug classes. Antiepileptics, antipsychotics and antidepressants each have a dozen drugs with different toxicities. Questions ask for the specific adverse effect or interaction (for example enzyme induction or teratogenicity). Learn each class as a table with the single most testable toxicity per drug.
3. Picking a diagnosis from one symptom. Psychiatric items test duration, functioning and exclusion of a medical or substance cause. A stem about mood symptoms may be pointing to hypothyroidism, intoxication or withdrawal. Read for onset, duration and substance history before choosing.

How to revise this system

• Draw the neuroanatomy. Spinal cord cross-section, brainstem levels, visual pathway and circle of Willis from memory. Attach the lesion syndrome to each drawing.
• Use a "lesion to deficit" table. Rows: location. Columns: arterial supply, findings, classic cause. Fill it from questions you miss.
• Table the drugs. One table for antiepileptics, one for antidepressants and mood stabilizers, one for antipsychotics and one for sedative-hypnotics and anesthetics. Include mechanism, key adverse effect and monitoring.
• Learn withdrawal and intoxication as pairs. For each substance: acute intoxication picture, withdrawal picture, treatment and complication.
• Do mixed blocks with the social sciences and multisystem rows. Capacity, consent, toxicology and pharmacology often meet in a psychiatric or neurologic scenario.

The study plan guide places this system after respiratory and renal in the 12-week plan, because neuroanatomy needs a full two-week window.

What the questions look like

Neurology items often give a short history, a focused neurologic examination and sometimes an imaging description. The question usually asks for the location of the lesion, the most likely diagnosis, the underlying mechanism or the best drug. Special senses items can include an image of the fundus or a visual field. Psychiatry items give a behavioral description with timeline and ask for the diagnosis, the drug, the adverse effect or the defense mechanism or developmental concept involved. We write original practice vignettes with the same structure, with five options and conventional units. They do not reproduce official or recalled items.

For the full table of systems and weights, return to the Step 1 hub.

A short note on time per topic

With 20 subtopics, divide your two weeks into four blocks of about three days: cortex and tracts, vascular and structural disease with neuropharmacology, special senses and neurodevelopment, and psychiatry. Finish each block with a 20-question mixed set from that block and one from the earlier ones. Keep a separate page for substance use, where intoxication, withdrawal and treatment form a compact table that earns marks in this row, in the social sciences row and in toxicology.