How to Probe Dynamics of Brain Function: A Narrative Review.

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• The brain is a complex dynamic system, but static analytical approaches limit understanding of its temporal processes.
• Static methods like time-averaged connectivity fail to capture dynamic processes essential for brain function and dysfunction.
• Psychiatric illnesses involve state fluctuations, necessitating dynamic analysis for deeper clinical insight.

Purpose of the Study:

• To review and organize current dynamic analytic approaches for studying brain function over time.
• To highlight methods for describing temporal brain activity, inferring causality, decoding latent dynamics, and simulating neural processes.
• To provide a framework for testing theories of brain function in clinical populations using dynamic modeling.

Main Methods:

• Review of dynamic modeling approaches including sliding-window correlations, temporal ICA, dynamic causal modeling, recurrent neural networks, and neural differential equations.
• Categorization of methods based on four research goals: describing temporal patterns, inferring causal mechanisms, decoding latent dynamics, and simulating neural processes.
• Discussion of method assumptions, clinical applications, limitations, and provision of links to open-access tools.

Main Results:

• Dynamic modeling quantifies temporal complexity, identifies causal influences, compresses activity into latent trajectories, and simulates data.
• Methods are organized by research goals, detailing representative techniques, their assumptions, clinical uses, and limitations.
• Open-access tools are linked for each method, facilitating application in clinical research.

Conclusions:

• Dynamic modeling represents a conceptual shift from static, data-driven descriptions to theory-informed tests of brain processes.
• These approaches enable direct testing of brain function theories in clinical populations.
• Aligning analytical tools with systems-level theories advances the study of brain function and dysfunction over time.