Which mechanism explains why repeated drug use leads to decreased sensitivity in the mesolimbic reward circuit?

💡 Explanation

Repeated drug use causes the brain to adapt, reducing its response to the drug over time. This is primarily due to the downregulation of dopamine receptors in the nucleus accumbens because this reduces the sensitivity of the reward circuit, therefore, greater amounts of the drug are required to achieve the same effect, rather than increased sensitivity from more receptors.

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