Interactions across hemispheres in prefrontal cortex reflect global cognitive processing

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Systems Neuroscience

Background:

• Brain functions rely on local neural networks and global signals like arousal.
• Understanding neural interactions between brain areas is crucial for dissecting complex cognitive functions.
• Previous studies often focused on single brain areas, limiting insights into inter-areal communication.

Purpose of the Study:

• To investigate neural interactions between prefrontal cortex areas in both hemispheres during a spatial memory task.
• To differentiate between local neural processing and global modulatory influences on neuronal activity.
• To develop and apply novel statistical methods for analyzing multi-area neural recordings.

Main Methods:

• Dual hemisphere recordings of prefrontal cortex activity in monkeys performing a spatial memory task.
• Application of a novel statistical approach, probabilistic canonical correlation analysis with factor analysis (pCCA-FA).
• Analysis of trial-to-trial variability in neuronal activity to identify shared and distinct neural signals.

Main Results:

• Significant shared variability was found among neurons within individual prefrontal cortex populations.
• A substantial portion of this shared variability was common across both hemispheres.
• The cross-hemispheric shared variability was strongly linked to an arousal process.
• The findings suggest that arousal modulates neural activity across distant brain regions.

Conclusions:

• Multi-area recordings, analyzed with advanced statistical techniques, can reveal brain functions obscured in single-area studies.
• Arousal plays a critical role in coordinating activity across widespread neural populations during cognitive tasks.
• The study provides a framework for leveraging simultaneous recordings from multiple brain regions to understand neural communication and function.