Likhon has Parkinson’s disease and is participating in a clinical trial for a new drug that increases the amplitude of EPSPs at neurons only in his basal ganglia. Of the following options, the most pronounced effect of this drug would be: a. Decreased likelihood of action potentials in basal ganglia neurons, which are associated with initiating movements b. Increased likelihood of action potentials in basal ganglia neurons, which are associated with initiating movements c. Increased likelihood of action potentials in basal ganglia neurons, which are associated with emotional processes d. Decreased likelihood of action potentials in basal ganglia neurons, which are associated with emotional processes

b. Increased likelihood of action potentials in basal ganglia neurons, which are associated with initiating movements

Explanation:

The substantia nigra is the principal site involved in the physiopathology of Parkinson´s disease.

Cells from this area degenerate and die progressively causing important degeneration in the central nervous system. The cells that die -with no known reason- are those that produce dopamine and proportionate dopaminergic innervation to the encephalon. In fact, almost all the symptoms exhibited by patients with the disease can be explained by the lack of dopamine in the substantia nigra.  

This neurotransmitter is used in the area to communicate neurons from the base ganglia. Ganglia are responsible for modulating and modifying movements.

The nigrostriatal system participates in the planning and automatic execution of learned movements. When the ganglia activity decreases, so it does the amount and velocity of movements, something typical of the disease.  

If the drug increases the amplitude of EPSPs at neurons in the basal ganglia, the action potentials in basal ganglia neurons would be expected to increase.