Switching Patterns of Cortical-Subcortical Interaction in the Human Brain

Area of Science:

• Neuroscience
• Brain Imaging
• Systems Neuroscience

Background:

• Spontaneous brain activity is crucial for neural function, but subcortical contributions remain unclear.
• A "corticocentric bias" often leads to analyzing cortical activity in isolation.
• Understanding cortical-subcortical interactions is vital for a comprehensive model of brain dynamics.

Purpose of the Study:

• To investigate dynamic functional connectivity (FC) between cortical and subcortical structures.
• To identify how subcortical regions influence spontaneous brain activity patterns.
• To challenge the "corticocentric bias" by including subcortical structures in whole-brain analyses.

Main Methods:

• Dynamic functional connectivity (FC) analysis.
• Utilized data from a large cohort of healthy human subjects (Human Connectome Project).
• Investigated synchronized fluctuations in cortical and subcortical activity.

Main Results:

• Cortical and subcortical FC shifts are synchronized.
• Limbic regions (hippocampus, amygdala) and subcortical nuclei (thalamus, basal ganglia) exhibit flexible coupling with cortical networks.
• Two recurring FC states were identified: limbic-default mode network and limbic-sensorimotor network coupling, with opposing patterns for thalamus/basal ganglia.

Conclusions:

• Cortical-subcortical interactions significantly shape spontaneous whole-brain FC patterns.
• The subcortex plays a critical role in large-scale spontaneous brain activity.
• Future research should integrate subcortical structures for a complete understanding of brain dynamics.