An individual develops tolerance to a drug affecting the reward circuit. What causes increased craving during drug withdrawal?

💡 Explanation

Reduced dopamine receptor sensitivity explains increased craving because the reward circuit requires greater drug stimulation to achieve the same level of satisfaction; therefore craving intensifies during withdrawal rather than experiencing opioid upregulation or other neurotransmitter imbalances.

• Following a deep skin wound, if fibroblast proliferation exceeds collagen degradation during remodeling, which consequence follows?
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• Why does reduced diastolic filling time in tachycardia decrease cardiac output?
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• An engineer studying cognitive function during sleep monitors a subject whose adenosine receptors are experimentally blocked. Which outcome is most likely regarding the subject's sleep architecture?