Cortical sites critical to language function act as connectors between language subnetworks.

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Computational Neuroscience

Background:

• Historically, language functions were thought to be localized in specific brain areas.
• Recent research suggests language relies on distributed neural networks across the cerebral cortex.

Purpose of the Study:

• To investigate the network properties of critical speech and language sites identified by brain stimulation.
• To differentiate network signatures associated with speech arrest versus language errors.

Main Methods:

• Utilized electrocorticography (ECoG) in sixteen participants during a word-reading task.
• Analyzed network connectivity (local, global, and inter-community) of stimulated cortical sites.
• Employed machine learning to classify site types based on their connectivity patterns.

Main Results:

• Cortical sites critical for speech and language exhibited distinct network signatures.
• Both speech arrest and language error sites showed reduced local and global connectivity.
• Sites causing language errors displayed higher inter-community connectivity, acting as network connectors.

Conclusions:

• A site's connectivity pattern within the language network is crucial for its function.
• These findings bridge the gap between focal stimulation effects and distributed brain network activity.
• Understanding these network properties aids in predicting and explaining language deficits after brain stimulation.