kaplan24 - nishi

[ArchivalUser]

A 63-year-old man has a resting tremor of his fingers and rigidity of his limbs and trunk. There is increased resistance when the arms or neck are flexed. His face looks expressionless. His memory is preserved, and sensation and strength are normal. Which of the following neuronal pathways is most likely affected?
A. Cerebello-rubro-thalamic
B. Basal nucleus of Meynert-cortex
C. Mesolimbic
D. Nigrostriatal
E. Striatonigral
F. Vermis-spinal motoneurons

[ArchivalUser]

e?

[ArchivalUser]

eee..?

[ArchivalUser]

DD

[ArchivalUser]

correct answer is D. Resting tremor, rigidity, and akinesia is the triad of neurologic signs characterizing Parkinson disease. This condition is caused by degeneration and death of dopaminergic neurons in the substantia nigra that project to the striatum (nigrostriatal pathway). Striatal neurons projecting back to the substantia nigra (choice E) are not affected.