Interactions across hemispheres in prefrontal cortex reflect global cognitive processing

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Systems Neuroscience

Background:

• Brain functions rely on local network processing and global signals like arousal.
• Understanding neural interactions across brain areas is crucial for dissecting complex cognitive functions.
• Single-area recordings may miss crucial cross-area communication dynamics.

Purpose of the Study:

• To investigate interactions between prefrontal cortex areas in both hemispheres during a spatial memory task.
• To differentiate global modulatory signals from local neural interactions.
• To reveal brain functions obscured by single-area recording limitations.

Main Methods:

• Dual hemisphere recordings of prefrontal cortex activity in monkeys.
• Utilized a novel statistical approach: probabilistic canonical correlation analysis with factor analysis (pCCA-FA).
• Analyzed trial-to-trial variability in neuronal responses to identify shared neural signals.

Main Results:

• Identified substantial shared neuronal variability within individual prefrontal cortex populations.
• Found that a significant portion of this shared variability was common across hemispheres.
• Linked this cross-hemispheric shared variability to an arousal process.

Conclusions:

• Multi-area recordings, combined with advanced statistical methods like pCCA-FA, can uncover hidden aspects of brain function.
• Arousal significantly modulates neural activity across distant brain regions, impacting cognitive tasks.
• This study provides a framework for analyzing large-scale neural recordings to understand brain-wide communication.