Synchronized activity in the midbrain dopamine system during internal nutrient learning

Ventral tegmental area dopamine neurons enter a distinct network state characterized by synchronized 0.8 Hz bursting after food ingestion.

• This synchronized activity extends the integration window for learning between immediate sensory cues and delayed nutrient signals.
• The 'sync state' emerges tens of seconds after eating begins, coinciding with the overlap of taste sensations and nutrient signals.
• This neural activity does not correlate with reward prediction error or motor signals.
• Silencing dopamine neurons during the overlap of taste and nutrient signals blocks the ability to learn about nutrients, without impacting food intake.
• Optogenetic stimulation that mimics this synchronized bursting can drive learning about nutrients even in the absence of actual food.

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