Time-varying synergy/redundancy dominance in the human cerebral cortex

Area of Science:

• Neuroscience
• Information Theory
• Brain Imaging

Background:

• Higher-order interactions are crucial for brain function.
• Interactions can be synergy-dominated or redundancy-dominated.
• The dynamic structure of these interactions remains largely unknown.

Purpose of the Study:

• To analyze the dynamic structure of synergy and redundancy in the fMRI BOLD signal during rest.
• To investigate moment-to-moment dominance of interactions across different scales.
• To understand how functional system dynamics relate to interaction types.

Main Methods:

• Multivariate information theory tools applied to fMRI BOLD signals.
• Analysis of 95 unrelated subjects during resting-state.
• Examination of interaction dynamics across various subset sizes of brain regions.

Main Results:

• The whole brain is predominantly redundancy-dominated, with some individuals showing no whole-brain synergy.
• Redundancy-dominated small brain region subsets exhibit complex dynamics and peak synergy/redundancy.
• Synergy occurs in functional systems during momentary disintegration, a pattern also seen in larger subsets.

Conclusions:

• Brain interactions exhibit highly structured temporal dynamics across multiple scales.
• Interacting nodes change smoothly and recur, highlighting the relevance of time-localized measures.
• Understanding these dynamics is key for future studies on behavior and cognition.