Visualization of functional and effective connectivity underlying auditory descriptive naming.

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Neurology

Background:

• Understanding brain network dynamics is crucial for interpreting cognitive processes.
• Focal epilepsy offers a unique model to study neural interactions due to localized disruptions.

Purpose of the Study:

• To visualize functional and effective connectivity within white matter networks in response to auditory descriptive questions.
• To investigate how different interrogative structures and semantic content influence neural pathways.

Main Methods:

• Investigated 40 Japanese-speaking patients with focal epilepsy.
• Estimated connectivity using cortical high-gamma dynamics and MRI tractography.

Main Results:

• Auditory wh-interrogatives enhanced inter-hemispheric functional connectivity (superior-temporal gyri) and decreased it (dorsolateral prefrontal regions).
• Processing concrete verbs/adverbs increased left intra-hemispheric connectivity via white matter pathways.
• Questions starting with 'what' versus 'where' increased neural engagement in the left posterior inferior-frontal gyrus and connectivity to the temporal lobe via the arcuate fasciculus.
• Overt responses enhanced inter-hemispheric connectivity between Rolandic areas; higher IQ correlated with less prolonged frontal engagement.

Conclusions:

• Visualization of directional neural interactions within white matter networks during overt naming is feasible.
• Auditory question phrasing influences listener network dynamics, even with similar meanings.