Orbitofrontal high-gamma reflects spike-dissociable value and decision mechanisms

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Brain-Machine Interfaces

Background:

• The orbitofrontal cortex (OFC) is vital for value-based decision-making.
• The role of local field potentials (LFPs) in OFC decision-making is not well understood.
• LFPs offer insights into subthreshold neural activity and potential for less invasive brain-machine interfaces (BMIs).

Approach:

• Recorded LFPs and multi-unit activity (MUA) simultaneously in monkeys during a value-based decision task.
• Compared the value- and decision-coding properties of high-gamma (HG) LFPs (50-150 Hz) with MUA.
• Analyzed representations of target values, value comparisons, and choice outcome prediction.

Key Points:

• Both HG LFPs and MUA represent target values with similar temporal dynamics.
• HG LFPs show unique value encoding, including monotonic increases with value and stronger encoding of value comparisons, distinct from MUA.
• HG value representations were more prominent in superficial cortical layers, suggesting different neuronal origins than MUA.

Conclusions:

• High-gamma LFPs provide distinct cognitive signals compared to MUA in the OFC.
• HG LFPs offer a promising, potentially less invasive, target for cognitive function-related BMIs.
• This research opens avenues for utilizing LFPs in advanced brain-machine interface applications.