Role of white-matter pathways in coordinating alpha oscillations in resting visual cortex

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Computational Neuroscience

Background:

• Posterior alpha-oscillations (≈ 10 Hz) are prominent in the human neocortex during rest.
• These oscillations are particularly strong in the visual cortex, including the primary visual cortex.
• The coordination mechanisms and white-matter pathways for these alpha-oscillations are not fully understood.

Purpose of the Study:

• To investigate the role of white-matter pathways in coordinating cortical alpha-oscillations.
• To determine the influence of primary visual cortex on alpha-oscillation coordination in higher-order visual areas.

Main Methods:

• Magnetoencephalography (MEG) to record brain activity.
• Diffusion tensor imaging (DTI) to analyze white-matter tracts.
• Biophysical modeling to simulate neural oscillations and connectivity.

Main Results:

• Alpha-oscillation amplitudes in the visual cortex are explained by propagation from the primary visual cortex.
• Both anatomical and functional connectivity strengths to the primary visual cortex correlated with alpha-amplitudes.
• White-matter pathways are crucial for coordinating alpha-oscillations across visual regions.

Conclusions:

• The primary visual cortex plays a significant role in coordinating alpha-oscillations in higher-order visual areas.
• Posterior alpha-oscillations are intrinsic to the visual system, potentially priming it for stimuli.
• These findings suggest a default-mode function for the visual system mediated by alpha-oscillations.