Functional and structural brain connectivity in disorders of consciousness

Area of Science:

• Neuroscience
• Cognitive Science
• Neurology

Background:

• Brain connectivity is crucial for consciousness, enabling integrated information processing.
• The relationship between functional brain interactions and underlying structural connections remains unclear.
• Disorders of consciousness (DoC) present diagnostic challenges, necessitating refined assessment methods.

Purpose of the Study:

• To investigate the relationship between functional and structural brain connectivity in patients with DoC.
• To assess the utility of connectivity metrics in differentiating vegetative state (VS) from minimally conscious state (MCS).
• To evaluate the role of specific cortico-cortical pathways within the Global Neuronal Workspace (GNW) theory.

Main Methods:

• Utilized electroencephalography (EEG) to measure functional connectivity (theta band median weighted symbolic mutual information).
• Employed magnetic resonance imaging (MRI) to quantify structural connectivity (fractional anisotropy).
• Analyzed data from 78 patients diagnosed with disorders of consciousness.

Main Results:

• Both functional and structural connectivity metrics successfully differentiated between VS and MCS patients.
• A significant positive correlation was found between functional and structural connectivity.
• This structure-function relationship was particularly evident in long-distance cortico-cortical bundles relevant to the GNW theory.

Conclusions:

• Multimodal assessment of brain connectivity offers valuable insights for diagnosing DoC.
• Findings support the GNW theory by demonstrating a link between structural pathways and functional integration.
• Connectivity metrics show promise for improving diagnostic accuracy and patient stratification in DoC.