Fred has parkinson's disease, a progressive neurodegenerative disease that affects motor skills. in addition to motor symptoms, fred has noticed changes in his mood, and he feels the need to smoke more cigarettes than he used to. it is likely that jeremy's is producing less than it needs to.

substania nigra; dopamine

Explanation:

The substantia nigra is a structure of basal ganglia. It is located in the midbrain. The substantia nigra has a role in brain function, it controls the movement of eyes, reward seeking, addiction, and motor planning. The death of neurons which secrete dopamine in the substantia nigra leads to Parkinson's disease.

Parkinson's disease is a disease of nervous system. It affects the movement of the body. The symptoms of the disease starts with a tremor in the hand. Tremors, stiffness and slow movement are also characteristics of this disease.

by going smokefree, you could improve the well-being of your friends, family, coworkers, and even your pets. here’s how the cigarettes you smoke affect the people around you.