Lesion localisation in the nervous system
Core concept
- Neurological signs localise to a specific level -- match the pattern to a single anatomical site before considering aetiology
- Cortex: contralateral weakness/sensory loss face+arm>leg (MCA) or leg>arm (ACA); cortical signs (aphasia, neglect, apraxia)
- Subcortical/internal capsule (lacunar): pure motor or pure sensory deficit, no cortical signs (no aphasia/neglect) -- small vessel disease
- Brainstem: crossed signs (ipsilateral cranial nerve + contralateral limb) -- localises the side and level precisely
- Spinal cord: bilateral, sensory level, sphincter involvement
3 more sections, plus exam facts
Premium unlocks every note across every specialty, and the full exam fact library behind it.
Get premium access