Medial Orbitofrontal, Prefrontal, and Amygdalar Circuits Support Dissociable Component Processes of Risk/Reward...

Area of Science:

• Neuroscience
• Decision Science
• Behavioral Economics

Background:

• The medial orbitofrontal cortex (mOFC) is crucial for decision-making under reward uncertainty, utilizing memory to predict outcomes.
• Its interconnectedness with the basolateral amygdala (BLA) and prelimbic (PL) cortex is known, but the specific roles of these circuits are unclear.

Purpose of the Study:

• To investigate the functional contribution of mOFC input and output pathways to risk/reward decision-making using chemogenetics.
• To elucidate the roles of mOFC-BLA and mOFC-PL circuits in processing reward value and context-dependent information.

Main Methods:

• Male rats were trained on a probabilistic discounting task with changing reward probabilities.
• Chemogenetic silencing was used to inhibit specific mOFC circuits, including descending projections to the BLA and inputs from the BLA and PL cortex.

Main Results:

• Silencing mOFC projections to the BLA impaired adjustments in choice bias with changing reward probabilities.
• Inhibiting mOFC inputs to the PL cortex led to more random choices, suggesting a role in processing win/loss information.
• PL inputs to the mOFC reduced the appeal of uncertain rewards and decreased sensitivity to losses.

Conclusions:

• mOFC interactions with the BLA and PL cortex support distinct processes in decision-making under risk and uncertainty.
• Specific pathways, such as mOFC→BLA and mOFC→PL, contribute to flexible value-based choices and context-dependent information processing.
• These findings clarify the functional roles of cortico-amygdalar and cortico-cortical circuits in decision-making and may inform understanding of psychiatric disorders.