The drug-action atlas

Enter through a molecule, a synapse, or a brain circuit. Change the conditions and trace what happens next.

All learning models

Explore the system

Trace dopamine pathways

Switch projections on and off without losing the anatomical relationships between source and target.

Trace dopamine pathways

Animate the diagram

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Predict, then check

Which projection connects the ventral tegmental area with the nucleus accumbens?NigrostriatalMesolimbic

Exploration and predictions are practice. They do not award mastery or XP.

Sources and model limits

Original schematic. Positions show relationships; structures and concentrations are not to scale.

Julien's Primer of Drug Action · 15 · 2 · Trace dopamine pathways · PDF 28, 29 · 2.14

Diagram zoom

Original schematic. Positions show relationships; structures and concentrations are not to scale.

Ventral tegmental area (VTA)

Dopamine source for mesolimbic and mesocortical projections.

Several drug mechanisms influence dopamine output directly or through local circuitry.

Inspect a structure

Mesolimbic · VTA → NAc

Ventral tegmental area → nucleus accumbens. Reinforcement, incentive motivation, and addiction-related learning; dopamine is not a complete explanation of addiction.

Mesocortical · VTA → PFC

Nigrostriatal · substantia nigra → striatum