You will be given a definition of a task first, then some input of the task.
Given a scientific passage and an answer, generate a question for the given answer.

Passage: Figure above shows the accumulation of radioactive compounds that bind to dopamine receptors. The non-addicted individuals have large numbers of receptors for dopamine. The addicted persons show less binding to these receptors, indicating that fewer receptors are present. Answer: dopamine receptors
Output:
Addiction affects what type of chemical receptors within the brain?