If a substance consistently floods the nucleus accumbens with dopamine, what is the most likely long-term consequence affecting the reward circuit?

💡 Explanation

Repeated overstimulation by a substance causes the brain to reduce the number of dopamine receptors in a process called downregulation, because this reduces the cell's sensitivity to the signal. Therefore, more of the substance is required to achieve the same rewarding effect, rather than experiencing enhanced sensitivity or a perpetually high response.

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