Causal Cortical and Thalamic Connections in the Human Brain

Area of Science:

• Neuroscience
• Brain Connectivity
• Computational Neuroscience

Background:

• The brain's functional architecture relies on causal connections between cortical and subcortical structures.
• Understanding these connections is crucial for deciphering brain function.

Purpose of the Study:

• To investigate causal connectivity between thalamic nuclei and cortical areas.
• To identify distinct spectral patterns resulting from brain area perturbations.

Main Methods:

• Electrical stimulation of thalamic and cortical regions in 27 participants.
• Analysis of 4864 electrode recordings across anterior, mediodorsal, and pulvinar thalamus, and cortex.
• Data-driven approach to dissociate spectral patterns.

Main Results:

• Three unique spectral patterns were identified following brain area stimulation.
• A novel waveform with delayed slow oscillations in bilateral cortices was observed after thalamic stimulation.
• Thalamus received signals from cortical stimulation before inter-cortical signal exchange.

Conclusions:

• Thalamic stimulation can influence bilateral cortical activity through a novel mechanism.
• The thalamus may act as an early receiver of cortical signals.
• Causal connectivity data can inform biologically-inspired computational models of brain architecture.