Dopamine is a neurotransmitter that when released in the brain tends to make a person feel happy. Certain drugs stop the synapses from removing neurotransmitters. When these drugs cause an increase in the amount of neurotransmitters in the synapses, which response would be increased?

If a drug prevents dopamine from being removed from synapses, more dopamine remains available to affect nearby cells. Because dopamine release tends to make a person feel happy, the response most likely to increase is happiness. Sleepiness, sadness, and alertness are not the response linked to dopamine in the question.

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