Large-scale brain dynamics are organized by a directional coordination hierarchy

Area of Science:

• Neuroscience
• Systems Neuroscience
• Cognitive Neuroscience

Background:

• The cortical hierarchy organizes brain structure and function.
• Its continuous expression in spontaneous neural activity is not well understood.

Purpose of the Study:

• To investigate the organization of resting-state brain dynamics along a directional coordination axis.
• To identify recurrent coordination modes and their stability.
• To examine alterations in this organization in schizophrenia.

Main Methods:

• Analysis of directional interregional coordination dynamics in resting-state fMRI data.
• Identification of three coordination regimes: feedback-dominated, feedforward-dominated, and integrative.
• Characterization of the coordination landscape across four independent cohorts.
• Assessment of alterations in schizophrenia and correlation with clinical variables.

Main Results:

• Resting-state brain dynamics exhibit a directional coordination axis mirroring hierarchical information flow.
• Three recurrent coordination modes (feedback, feedforward, integrative) form a stable, low-dimensional landscape.
• Schizophrenia reorganizes this landscape, reducing feedback persistence and increasing integrative persistence, leading to altered dynamics.
• These alterations correlate with symptom severity, cognition, and medication.

Conclusions:

• Directional functional dynamics are a fundamental property of large-scale brain organization.
• Schizophrenia involves a selective reorganization of this dynamic landscape.
• These findings provide a clinically informative axis for understanding brain function and dysfunction.