Striatum-wide dopamine encodes trajectory errors separated from value

Area of Science:

• Neuroscience
• Computational Neuroscience
• Animal Behavior

Background:

• Goal-directed navigation relies on evaluating movement relative to goals.
• Striatal dopamine signals reward value and motivation, but its role in behavioral guidance is unclear.

Purpose of the Study:

• To investigate how dopamine in the striatum incorporates an animal's trajectory for effective behavioral guidance.
• To determine if dopamine signals trajectory errors independently from learned cue values.

Main Methods:

• Cue-evoked striatal dopamine release was measured in mice using multifibre array recordings.
• Locomotion and visual flow data were analyzed to compute trajectory errors.
• A reinforcement learning algorithm was used to model dopamine signaling.

Main Results:

• Striatal dopamine release encodes bidirectional trajectory errors relative to optimal goal trajectories.
• Trajectory error signals were independent of dopamine increases reflecting learned cue value.
• Overlapping yet separable representations of trajectory error and cue value were observed in the striatum.

Conclusions:

• Dopamine in the striatum provides distinct signals for motivation and behavioral guidance.
• Functionally distinct dopamine signals are multiplexed across striatal regions to facilitate goal-directed behavior.