Abnormal characteristic static and dynamic functional network connectivity in idiopathic normal pressure...

Area of Science:

• Neuroscience
• Medical Imaging
• Systems Biology

Background:

• Idiopathic normal pressure hydrocephalus (iNPH) is a neurodegenerative condition.
• Key symptoms include gait disturbance, dementia, and urinary dysfunction.
• The underlying neural network mechanisms of iNPH remain unclear.

Purpose of the Study:

• Investigate resting-state functional connectivity (rs-FC) abnormalities in iNPH.
• Analyze both static (sFNC) and dynamic (dFNC) functional network connectivity.
• Correlate connectivity changes with clinical symptoms before and after shunt surgery.

Main Methods:

• Compared sFNC and dFNC in 33 iNPH patients and 23 healthy controls (HCs).
• Assessed alterations in default mode network (DMN), somatomotor network (SMN), visual network (VN), and dorsal attention network (DAN).
• Examined temporal properties and variability of dFNC states.

Main Results:

• iNPH patients showed generally decreased sFNC and dFNC.
• Reduced sFNC within DMN and between SMN-VN correlated with symptoms.
• dFNC temporal properties, particularly state-4 variability, were sensitive for iNPH identification and symptom correlation.
• Increased temporal variability in DAN and altered instantaneous FC were observed in iNPH.

Conclusions:

• Dynamic functional network connectivity (dFNC) appears to be a more sensitive biomarker for altered brain function in iNPH.
• dFNC provides additional insights into the pathophysiological mechanisms of iNPH.
• These findings may aid in diagnosis and understanding disease progression.