A recent study published by researchers at MIT’s McGovern Institute for Brain Research has shed new light on the process of reinforcement learning in the brain, suggesting a need to revise current understanding.
A recent study published by researchers at MIT’s McGovern Institute for Brain Research has shed new light on the process of reinforcement learning in the brain. The study suggests that neuroscientists’ understanding of this process may need to be revised.
Reinforcement learning is a type of learning where an organism learns to associate certain cues or behaviors with rewards or punishments. Dopamine, a neurotransmitter, plays a critical role in teaching people and other animals about these associations.
The study, led by Ann Graybiel, found surprising patterns of dopamine signaling that suggest neuroscientists may need to refine their model of how reinforcement learning occurs in the brain. The team’s findings were published recently in the journal Nature Communications.
In the study, researchers introduced a second light into its experimental setup, which did not signal a reward. Mice watched as either light was given as the cue, one at a time, with water accompanying only the original cue. The results showed that when the mice saw the reward-associated light, dopamine release went up in the centromedial striatum and surprisingly, stayed up until the reward was delivered.
The study’s findings suggest that neuroscientists’ understanding of reinforcement learning may need to evolve as part of the field’s deepening understanding of the brain. The results also indicate that sustained dopamine release may be linked to working memory in other parts of the brain.
- mit.edu | Revisiting reinforcement learning
