Different dorsal striatum circuits mediate action discrimination and action generalization.

Area of Science:

• Neuroscience
• Behavioral Science

Background:

• Action generalization allows animals to adapt learned behaviors to new situations, enhancing efficiency.
• Generalizing actions to novel instruments is crucial for navigating changing environments, but can also be maladaptive.

Purpose of the Study:

• To investigate the neural mechanisms underlying action generalization and discrimination.
• To explore the distinct roles of the dorsolateral striatum (DLS) and dorsomedial striatum (DMS) in action generalization.

Main Methods:

• Mice were trained on a lever-pressing task with reinforcement schedules biasing habitual or goal-directed behaviors.
• Selective excitotoxic lesions were applied to the DLS and DMS.
• Behavioral analysis assessed action generalization and discrimination to novel levers.

Main Results:

• Action generalization was more pronounced in mice employing habitual strategies compared to goal-directed ones.
• DLS lesions impaired action generalization to a novel lever.
• DMS lesions impaired action discrimination and biased mice towards action generalization.

Conclusions:

• The DLS and DMS exhibit opposing functions in the generalization of previously learned actions to novel instruments.
• These striatal circuits appear to compete, influencing the expression of generalization in new contexts.