Prefrontal neuronal ensembles link prior knowledge with novel actions during flexible action selection

Area of Science:

• Neuroscience
• Cognitive Science
• Computational Neuroscience

Background:

• Decision-making relies on current perceptions or internal environmental models.
• The medial prefrontal cortex (mPFC) and hippocampus are crucial for model-based decision-making.
• The precise computational mechanisms remain unclear.

Purpose of the Study:

• To investigate the neural dynamics of model-based decision-making.
• To explore the roles of the medial prefrontal cortex (mPFC) and hippocampus in flexible action selection.

Main Methods:

• Recorded medial prefrontal cortex (mPFC) neuronal spiking activity in rats.
• Analyzed hippocampal oscillatory activity during flexible action selection.
• Examined neural representations of associative environmental structures and actions.

Main Results:

• The mPFC reinstates representations of environmental associative structures during action selection.
• Synchronous neural firing between associative structure and action neurons in the mPFC occurs during reactivation.
• Functional coupling strengthens between these neurons, leading to adaptive actions.
• Hippocampal sharp-wave ripples selectively enhance functional coupling in cue-coding neurons.

Conclusions:

• The mPFC independently forms self-organized neuronal ensembles linking prior knowledge with novel actions.
• Lack of direct experience disconnects the mPFC from the hippocampus for independent dynamic formation.
• These findings elucidate the neural basis of flexible, model-based decision-making.