Summary: For decades neuroscientists have puzzled over how a single chemical—dopamine—can control two very different functions: reinforcing reward-based learning and energizing physical movement. New research using rats reveals a timing-based “switch” mediated by a second neurotransmitter, acetylcholine. When dopamine release follows a fall in acetylcholine, it promotes learning; when dopamine coincides with an acetylcholine burst, it drives movement vigor. This interaction occurs within tens of milliseconds and points to a fresh framework for understanding and treating disorders such as Parkinson’s disease, schizophrenia, and depression.
Researchers at New York University measured both dopamine and acetylcholine in the dorsomedial striatum while rats performed a decision-making task that combined learning and movement. The animals learned the significance of sound cues that indicated the location and amount of a water reward, then moved to collect that water. The recordings showed that subtle differences in the timing of neurotransmitter signals predicted whether dopamine would influence synaptic plasticity and future behavior or predict the intensity of imminent movements.
Key Facts
- See-saw dynamic: Dopamine’s effect depends on acetylcholine timing. A drop in acetylcholine as dopamine rises favors learning; a simultaneous rise in both favors movement vigor.
- Precision timing: The functional outcome—learning versus movement—can be determined by a window of only tens of milliseconds.
- Dual roles reconciled: This timing mechanism explains how dopamine can serve both reinforcement learning and motor control without needing distinct chemicals for each role.
- Clinical relevance: Misalignment of this timing may contribute to motor and cognitive symptoms in Parkinson’s disease, schizophrenia, and depression, suggesting new targets for interventions.
Study details and findings
The team used optical sensors to record rapid fluctuations of dopamine and acetylcholine in behaving rats. They observed distinct patterns around reward cues: some cues triggered brief pauses in cholinergic (acetylcholine) activity that were out of phase with dopamine signals, while other cues produced cholinergic bursts that aligned with dopamine. When dopamine occurred after a cholinergic dip, it predicted changes in future behavior and altered dorsomedial striatum firing on subsequent trials—consistent with a role in reinforcement and learning. When dopamine coincided with cholinergic bursts, it preceded and predicted vigorous contralateral orienting movements, indicating a role in energizing movement.
These findings support a model in which cholinergic dynamics act as a gate: depending on the instantaneous pattern of acetylcholine release, dopamine signals are routed toward synaptic plasticity and learning or toward the control of motor vigor. That routing takes place on a millisecond timescale, providing an elegant solution to how a single neuromodulator can perform two distinct functions in the same brain region.
Clinical significance
Disorders that involve dopaminergic dysfunction—most prominently Parkinson’s disease, but also schizophrenia and depression—may reflect disruptions in the timing relationship between dopamine and acetylcholine. If the coordination between these signals is lost, the brain may inappropriately assign dopamine’s influence to learning when it should be mobilizing movement, or vice versa. Understanding this timing switch opens the possibility of therapies that target the interaction between these neurotransmitters rather than simply raising or lowering dopamine levels globally.
Authors and funding
The senior author is Christine Constantinople, professor at NYU’s Center for Neural Science. Co-authors include Hee Jae Jang, Carla Golden, and Royall McMahon Ward. The research was supported by grants from the National Institutes of Health (DP2MH126376, R01MH136272) and an Alfred P. Sloan Research Fellowship.
Key Questions Answered
A: The brain uses dopamine efficiently for both functions. Acetylcholine acts as a timing-based controller that instructs dopamine whether to drive learning or to energize movement at any given moment.
A: Misalignment may underlie symptoms of neurological and psychiatric conditions. If the switch between learning and movement functions is disrupted, behavior and motor control can be impaired, as seen in disorders like Parkinson’s and schizophrenia.
A: Potentially yes. Rather than broadly increasing or decreasing dopamine, therapies could aim to restore or modulate the precise timing relationship between dopamine and acetylcholine to achieve more specific outcomes.
Editorial notes
- This article was edited by a Neuroscience News editor.
- Journal paper was reviewed in full and additional context was provided by the editorial team.
About this neuroscience research news
Author: James Devitt
Source: NYU
Contact: James Devitt – NYU
Image: Image credited to Neuroscience News
Original Research: Open access. “Acetylcholine demixes heterogeneous dopamine signals for learning and moving” by Hee Jae Jang, Royall McMahon Ward, Carla E. M. Golden & Christine M. Constantinople. Nature Neuroscience. DOI: 10.1038/s41593-026-02227-x
Abstract
Acetylcholine demixes heterogeneous dopamine signals for learning and moving
Midbrain dopamine neurons promote reinforcement learning and movement vigor. An outstanding question is how dopamine-recipient neurons in the striatum parse these heterogeneous signals. Previous work suggested cholinergic striatal interneurons may gate dopamine-dependent plasticity, but this had not been tested in behaving animals. Using rats performing a decision-making task with both reward-related and movement-related events, optical measurement of dopamine and acetylcholine release in the dorsomedial striatum revealed that reward cues evoke cholinergic pauses and bursts with different phase relationships to dopamine. When dopamine lagged cholinergic dips, dopamine predicted future behavior and dorsomedial striatum firing on subsequent trials. When dopamine preceded cholinergic dips, there was no observable relationship between dopamine and learning. Finally, when dopamine was coincident with cholinergic bursts, it predicted the vigor of contralateral orienting movements. These findings suggest that cholinergic dynamics determine whether dopamine promotes vigor or learning, depending on the instantaneous behavioral context.