Tuesday Nov 21, 2023
Lead: Fast dopamine increases drug reward
Lead Story:
Neural circuit selective for fast but not slow dopamine increases in drug reward🔓
Nature Communications
The authors note that rapid delivery to the brain when drugs are injected or smoked results in more severe substance use disorders. They used functional MRI and PET scans to monitor dopamine increases while subjects (n=20) received methylphenidate either orally or intravenously. Intravenous methylphenidate caused a more rapid increase in dopamine than oral. Activity in the medial prefrontal cortex decreased in both groups but was more pronounced with intravenous methylphenidate. However, only intravenous methylphenidate produced increased activity in the dorsal anterior cingulate cortex and insula that was reflected in the subjective rating of “high.” This brain region was activated only by intravenous methylphenidate and the associated rapid increase in dopamine.