The rodent lateral orbitofrontal cortex as an arbitrator selecting between model-based and model-free learning...

Area of Science:

• Neuroscience
• Cognitive Science
• Computational Psychiatry

Background:

• The orbitofrontal cortex (OFC) is increasingly understood through associative and reinforcement learning theories.
• OFC function is linked to representing outcome values, sensory properties, and inferring latent states in cognitive maps.
• Existing models explain some OFC dysfunction effects but require refinement.

Purpose of the Study:

• To review the evolution of understanding OFC function.
• To examine cardinal deficits (reversal learning, outcome devaluation) and initial acquisition deficits following OFC dysfunction.
• To propose a refined model of OFC function.

Main Methods:

• Review of theoretical advances in associative and reinforcement learning.
• Analysis of findings from causal manipulation studies in rodents and primates.
• Consideration of recent experimental results on OFC dysfunction.

Main Results:

• OFC dysfunction impacts reversal learning and outcome devaluation.
• Contrary to prior assumptions, OFC dysfunction also affects initial acquisition learning.
• A potential role for OFC in arbitrating between model-free and model-based learning systems is proposed.

Conclusions:

• The OFC's role extends beyond value representation to include arbitration between learning systems and offline updating.
• Distinct OFC subregions, like the lateral OFC in rodents, may contribute to specific aspects of cognitive map formation and utilization.
• Refined models are needed to fully capture the complexity of OFC function in learning and cognition.