PART 3 — BRAIN
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Study use: Rapid neuroanatomy, localization, stroke, neurocritical care, trauma, seizures, demyelination, movement disorders, dementia, hydrocephalus, and brain-tumor revision. Emergency points are intentionally concise and must be interpreted with timing, neurologic status, imaging, age, and clinical context.
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Priority Guide: 🔴 Core / Must Know | 🟠 Important | 🟡 Additional
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🎯 High-Yield Overview
- Broca: nonfluent speech with relatively preserved comprehension; Wernicke: fluent meaningless speech with impaired comprehension.
- MCA: face/arm > leg; ACA: leg > arm ± abulia/incontinence; PCA: homonymous hemianopia ± macular sparing.
- Acute focal deficit: glucose + ABC + last-known-well → NCCT head → vascular imaging/reperfusion assessment when appropriate.
- Raised ICP: headache, vomiting, papilledema, altered consciousness; Cushing response = hypertension + bradycardia + abnormal respiration.
- Uncal herniation: ipsilateral fixed dilated pupil; tonsillar herniation: medullary compression/cardiorespiratory failure.
- DAI: severe coma out of proportion to CT after acceleration/deceleration; MRI/SWI is more sensitive.
- GCS = E4 V5 M6 = 15; score ≤8 = severe impairment/airway concern in appropriate trauma settings.
- Status epilepticus: seizure ≥5 min or recurrent seizures without recovery → benzodiazepine first.
- NPH: magnetic gait + cognitive decline + urinary symptoms; gait usually appears first.
- Parkinson: bradykinesia + rigidity ± resting tremor; Lewy-body dementia: fluctuations + visual hallucinations + parkinsonism.
- Huntington: AD CAG expansion on chromosome 4 → caudate atrophy + chorea + psychiatric/cognitive decline.
- GBM: necrotic infiltrative adult tumor with pseudopalisading; meningioma: dural tail + psammoma bodies; oligodendroglioma: fried-egg + chicken-wire.
1. CEREBRAL CORTEX, HIGHER FUNCTIONS & APHASIA
2. CEREBROVASCULAR DISEASE & STROKE LOCALIZATION
3. RAISED ICP, CEREBRAL EDEMA & HERNIATION
4. TRAUMATIC BRAIN INJURY, GCS & CONSCIOUSNESS STATES