Neurology

~7% of blueprint

Stroke, seizures, headache, neurodegenerative disease.

Disease Profiles

Region: Arterial ring at the base of the brain.
Key Structures: ACA, MCA, PCA linked by the anterior & posterior communicating arteries; fed by the internal carotids & basilar artery.
Clinical Correlation: MCA stroke → contralateral face/arm weakness + aphasia (dominant); ACA → leg > arm; PComm aneurysm → CN III palsy.

High-Yield Pearl

MCA is the most common stroke territory — face & arm are affected more than the leg.

Region: White matter of the spinal cord.
Key Structures: Dorsal columns (fine touch/proprioception), spinothalamic tract (pain/temperature), lateral corticospinal tract (motor).
Clinical Correlation: Cord hemisection (Brown-Séquard) → ipsilateral motor & proprioception loss with contralateral pain/temperature loss.

High-Yield Pearl

Spinothalamic fibers cross at the level of entry; dorsal columns & corticospinal tracts cross in the medulla.

Region: Ventricular system of the brain.
Key Structures: Lateral ventricles → foramen of Monro → 3rd ventricle → cerebral aqueduct → 4th ventricle → Luschka/Magendie → subarachnoid space → arachnoid granulations.
Clinical Correlation: Flow obstruction → noncommunicating hydrocephalus; impaired reabsorption → communicating hydrocephalus.

High-Yield Pearl

Normal pressure hydrocephalus triad — wet, wobbly, wacky (incontinence, gait apraxia, dementia).