Phase-dependent stimulation response is shaped by the brain's dynamic functional connectivity

Area of Science:

• Computational neuroscience
• Cognitive neuroscience
• Neuroimaging

Background:

• External brain stimulation is a key tool for studying and modifying cognitive functions.
• Its clinical potential lies in restoring dysfunctional neural dynamics.
• Stimulation effects are known to depend on the brain's ongoing activity.

Purpose of the Study:

• To investigate how brain stimulation effects are influenced by local and global brain dynamics.
• To explore the role of oscillatory phase and functional connectivity in stimulation outcomes.
• To assess the impact of functional network awareness on predicting stimulation effects.

Main Methods:

• Connectome-based whole-brain computational modeling.
• Simulation of single-pulse stimulation across different brain regions.
• Analysis of stimulation effects based on regional oscillatory phase and transient functional connectivity.
• Machine learning models to predict stimulation outcomes.

Main Results:

• Stimulation effects are highly dependent on the phase of regional neural oscillations.
• The transient network of functional connectivity at the time of stimulation significantly modulates its impact.
• External brain stimulation can induce global state switching in brain dynamics.
• Functional network-aware measures improved prediction of stimulation effects by up to 40%.

Conclusions:

• The efficacy and outcome of external brain stimulation are critically dependent on the brain's intrinsic functional connectivity dynamics.
• Characterizing these dynamics is essential for enhancing the reliability and precision of brain stimulation therapies.
• This work highlights the importance of dynamic network states in understanding brain function and therapeutic interventions.