Neural responses in macaque prefrontal cortex are linked to strategic exploration

Area of Science:

• Neuroscience
• Cognitive Science
• Primatology

Background:

• Humans strategically explore to gather future-beneficial information.
• Primates' strategic exploration and its neural basis remain largely unknown.

Purpose of the Study:

• Investigate if monkeys use strategic exploration based on potential information gain.
• Examine if monkeys adjust exploration based on choice-information contingency and counterfactual feedback.

Main Methods:

• Designed a sequential choice task for monkeys.
• Introduced counterfactual feedback about unchosen options.
• Analyzed neural activity in anterior and mid-cingulate cortex (ACC/MCC) and dorsolateral prefrontal cortex (dlPFC), and medial orbitofrontal cortex (OFC).

Main Results:

• Monkeys decreased reliance on expected value when exploration was beneficial, independent of uncertainty.
• Strategic exploration signals were found in ACC/MCC and dlPFC, active when choosing low-value options.
• Strategic exploration was abolished by counterfactual feedback.
• Medial OFC activity correlated with learning from counterfactual outcomes, representing reward prediction errors.

Conclusions:

• ACC/MCC-dlPFC circuits support strategic exploration by counteracting expected value signals.
• Medial OFC circuits support learning from counterfactual outcomes.
• These circuits enable adaptive foraging by balancing exploitation and exploration.