<prompt> Answer this question truthfullyWhat are the ventral tegmentum and substantia nigra pars compacta, and what neurotransmitter is synthesized by these structures?  <response>: <reason> The ventral tegmentum and substantia nigra pars compacta are structures in the brain, and they are responsible for the synthesis of dopamine, a neurotransmitter involved in reward, motivation, and movement control. 