A computational model of how cholinergic interneurons protect striatal-dependent learning

Area of Science:

• Neuroscience
• Computational Neuroscience
• Behavioral Neuroscience

Background:

• Skill acquisition critically depends on learning environmental relevance.
• The striatum plays a crucial role in motor control and habit formation.
• Cholinergic interneurons, specifically tonically active neurons (TANs), are implicated in striatal function.

Purpose of the Study:

• To propose and test a neurobiologically detailed theory of how environmental relevance is learned during skill acquisition.
• To investigate the role of tonically active neurons (TANs) in mediating this learning process.
• To provide a computational model explaining TAN function in learning and behavior.

Main Methods:

• Development of a neurobiologically detailed theory centered on TANs.
• Computational modeling of the proposed theory.
• Testing the model against single-cell recording data and behavioral phenomena.

Main Results:

• The theory posits that TANs exert tonic inhibition, which is released by pausing in rewarding environments.
• TAN pausing facilitates the learning and expression of striatal-dependent behaviors.
• TANs ceasing to pause when rewards are absent protects learned behaviors from decay.
• The computational model successfully accounts for existing neurophysiological and behavioral data, including rapid reacquisition after extinction.

Conclusions:

• Tonically active neurons (TANs) are a key neural substrate for learning the environmental relevance of skills.
• The proposed TAN pausing mechanism provides a unified explanation for learning, behavioral expression, and memory consolidation in the striatum.
• Computational modeling supports the theory's ability to explain complex learning phenomena.