Which statement is true about dopamine?

• A. Dopamine decreases during pleasurable experiences.
• B. Dopamine is the primary neurotransmitter responsible for muscle contraction.
• C. Dopamine is only found in the peripheral nervous system.
• D. Dopamine is involved in the brain's reward and motivation pathways.

Answer: (D)

Verified step by step guidance

1. Understand that dopamine is a neurotransmitter, a chemical messenger that transmits signals in the brain and other areas of the nervous system.
2. Recall that dopamine plays a key role in the brain's reward system, influencing motivation, pleasure, and reinforcement learning.
3. Recognize that dopamine levels typically increase during pleasurable experiences, which contradicts the statement that dopamine decreases during such experiences.
4. Know that dopamine is not the primary neurotransmitter responsible for muscle contraction; that role is mainly played by acetylcholine.
5. Remember that dopamine is found primarily in the central nervous system (brain), not only in the peripheral nervous system, and it is involved in reward and motivation pathways.