Low-dimensional criticality embedded in high-dimensional awake brain dynamics.

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• The dynamical regime of cortical neurons (strongly vs. weakly correlated) is crucial for information processing.
• Decades of research have debated which regime dominates, with conflicting findings.

Purpose of the Study:

• To resolve the debate on cortical neuron dynamical regimes.
• To investigate the coexistence of typically incompatible dynamical regimes within local cortical circuits.

Main Methods:

• Analysis of neural activity in awake mouse motor cortex.
• Identification and separation of dynamical regimes into distinct subspaces.
• Utilizing computational modeling to validate findings.

Main Results:

• Two dynamical regimes coexist in separate subspaces within the same cortical circuit.
• A low-dimensional critical subspace with moderate correlations was identified at long timescales.
• A high-dimensional, desynchronized subspace was found, potentially optimizing input discrimination.

Conclusions:

• The cortex multiplexes dynamical regimes across different subspaces by leveraging its high dimensionality.
• The coexistence of critical and desynchronized dynamics explains previous discrepancies in research.
• This multiplexing strategy enhances information processing capabilities.