Which of the following best explains why psychoactive drugs often make people feel good?

• A. They increase the activity of neurotransmitters like dopamine in the brain's reward pathways, leading to pleasurable sensations.
• B. They block all sensory input to the brain, preventing negative emotions.
• C. They directly increase the number of neurons in the brain, resulting in enhanced mood.
• D. They permanently alter genetic material to produce long-term happiness.

Answer: (A)

Verified step by step guidance

1. Understand that psychoactive drugs affect the brain's chemistry, particularly by interacting with neurotransmitters, which are chemical messengers between neurons.
2. Identify the key neurotransmitter involved in feelings of pleasure and reward, which is dopamine, and recognize that many psychoactive drugs increase dopamine activity in specific brain regions.
3. Recognize that the brain's reward pathways, such as the mesolimbic pathway, are responsible for processing pleasurable sensations and reinforcing behaviors.
4. Analyze why blocking all sensory input or increasing neuron numbers is unlikely to cause immediate pleasurable feelings, as these do not directly influence neurotransmitter activity related to reward.
5. Conclude that the best explanation is that psychoactive drugs increase the activity of neurotransmitters like dopamine in the brain's reward pathways, leading to pleasurable sensations.