Brain/spinal tracts, classic lesions and their deficits, and high-yield neuro pathology.
42 cards · mixed cards · AI-written, checked twice. Edit anything.
- Where does the corticospinal tract originate?
Show answer
Motor cortex (Brodmann area 4), premotor cortex (area 6), and supplementary motor area- What percentage of corticospinal tract fibers decussate at the pyramids of the medulla?
Show answer
Approximately 90 percent; the remaining 10 percent descend ipsilaterally in the ventral corticospinal tract- What does a positive Babinski sign indicate?
Show answer
UMN lesion, usually involving the corticospinal tract- At what level do spinothalamic tract fibers cross the midline after entering the spinal cord?
Show answer
1-2 segments rostral to entry (they synapse in the dorsal horn and immediately cross)- What sensory pattern occurs with a unilateral spinothalamic tract lesion in the spinal cord?
Show answer
Contralateral loss of pain and temperature sensation beginning 1-2 segments below the lesion- In Brown-Sequard syndrome, what is the pattern of sensory loss?
Show answer
Ipsilateral loss of proprioception and vibration (dorsal columns) and contralateral loss of pain and temperature (spinothalamic tract)- Where do dorsal column fibers decussate?
Show answer
In the medulla via internal arcuate fibers that cross at the medullary pyramids- Which dorsal column tract carries lower extremity proprioception and vibration?
Show answer
Fasciculus gracilis (cuneatus carries upper extremity)- Which dorsal column tract carries upper extremity proprioception and vibration?
Show answer
Fasciculus cuneatus (gracilis carries lower extremity)- Weber syndrome results from a lesion in which part of the brainstem?
Show answer
Ventral midbrain, affecting CN III fascicles and the cerebral peduncle- What are the clinical findings in Weber syndrome?
Show answer
Ipsilateral CN III palsy (ptosis, down-and-out eye, dilated pupil) with contralateral hemiparesis- What artery occlusion causes Wallenberg syndrome (lateral medullary syndrome)?
Show answer
Posterior inferior cerebellar artery (PICA), resulting in lateral medullary infarction- Claude syndrome involves a lesion of which midbrain structure?
Show answer
Dorsal midbrain (tegmentum), involving the red nucleus and CN III fascicles, characterized by ipsilateral CN III palsy with contralateral cerebellar signs (ataxia/tremor).- Central cord syndrome is classically caused by what mechanism?
Show answer
Hyperextension injury (usually in elderly with cervical spondylosis), affecting the central gray matter- What is the classic motor pattern in central cord syndrome?
Show answer
Disproportionate upper extremity weakness compared to lower extremities (cape-like or sacral-sparing distribution)
FlashKeepers