In chronic addiction, which altered circuit dynamic explains why an individual experiences decreased satisfaction from natural rewards?

💡 Explanation

Addiction leads to a downregulation of dopamine D2 receptors in the nucleus accumbens because the brain attempts to compensate for the overstimulation of the reward circuit. Therefore, natural rewards produce less dopamine release, resulting in reduced pleasure, rather than altered serotonin, GABAergic activity, or opioid receptor levels.

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