Causal and directional elements of global brain dynamics.

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• Mammalian cognition relies on coordinated neural activity across large-scale brain networks.
• Principles governing this large-scale neural integration are not well understood.

Purpose of the Study:

• To uncover conserved spatiotemporal regularities in spontaneous cortex-wide neural activity.
• To identify governing principles of large-scale neural integration in the mammalian brain.

Main Methods:

• Developed novel genetically-encoded activity sensors for cortex-wide neural recording over long timescales.
• Applied unbiased computation to identify directional spatiotemporal elements in neural activity.
• Utilized patterned optogenetic stimulation and activity imaging to test causal rules.
• Investigated drug effects on neural dynamics and element structure.
• Employed all-optical sensing/control in a visual detection task.

Main Results:

• Identified conserved directional spatiotemporal patterns (directional elements) across neuronal cell types and frequency spectra, including gamma rhythms.
• Discovered that the propagation structure of these elements encodes a causal control hierarchy, with source regions driving recruitment.
• Demonstrated robustness of directional element structure to psychotropic drugs, despite reshaping of network dynamics.
• Showed contributions of these conserved dynamics to enhanced sensorimotor behavioral performance.

Conclusions:

• Conserved large-scale cortical dynamics, characterized by directional elements and a causal hierarchy, play a fundamental role in mammalian cognition.
• These principles of neural integration are stable across different neural and behavioral states.
• Targeting these dynamics offers insights into neural computation and sensorimotor behavior.