Altered white matter functional pathways in Alzheimer's disease

Area of Science:

• Neuroscience
• Medical Imaging
• Systems Biology

Background:

• Alzheimer's disease (AD) involves gray matter (GM) dysfunction and white matter (WM) damage.
• The functional connectivity within WM and its relationship to GM networks in AD remain unclear.

Purpose of the Study:

• To investigate abnormalities in WM and GM functional networks and the corpus callosum across AD stages.
• To explore the relationship between WM functional networks (WM-FNs) and GM functional networks.

Main Methods:

• Functional connectivity (FC) and graph theory analysis were applied to a public dataset.
• Analysis focused on WM-FNs, GM networks, and the corpus callosum in controls and AD patients.

Main Results:

• AD patients showed decreased FC between deep WM-FNs and the corpus callosum splenium, and between sensorimotor/occipital WM-FNs and GM visual networks.
• Increased FC was observed between deep WM-FNs and GM sensorimotor networks.
• Graph theory metrics revealed widespread reductions in network integration and altered modular interactions in AD.

Conclusions:

• Abnormal integration of functional networks, particularly involving WM-FNs, is characteristic of Alzheimer's disease.
• These WM functional pathway abnormalities connect to the corpus callosum and GM, correlating with AD.
• This study offers a novel perspective on AD pathophysiology through the lens of WM functional networks.