Study on structural atrophy changes and functional connectivity measures in Alzheimer's disease

Area of Science:

• Neuroimaging
• Neurology
• Biomarkers

Background:

• Alzheimer's disease (AD) is marked by amyloid plaques and neurofibrillary tangles.
• Default Mode Network (DMN) dysfunction is implicated in AD pathogenesis.
• Distinguishing between normal cognition and AD stages requires sensitive diagnostic tools.

Purpose of the Study:

• To compare the efficacy of functional connectivity and structural atrophy measures in detecting Alzheimer's disease.
• To investigate alterations in DMN functional connectivity across different cognitive impairment stages.
• To evaluate the potential of neuroimaging biomarkers for early AD detection.

Main Methods:

• Utilized resting-state functional MRI and MP-RAGE imaging from the Alzheimer's Disease Neuroimaging Initiative.
• Classified 80 subjects into four groups (cognitively normal, early MCI, late MCI, AD) based on MMSE scores.
• Analyzed DMN functional connectivity using CONN toolbox and structural atrophy with FMRIB FIRST software.

Main Results:

• Observed significant gray matter loss in AD patients compared to cognitively normal individuals.
• Found increased negative DMN functional connectivity in the AD group.
• Functional connectivity metrics demonstrated higher correlation with MMSE scores and larger AUC in ROC analysis compared to atrophy measures.

Conclusions:

• Functional connectivity alterations in the DMN are more sensitive indicators of Alzheimer's disease than structural atrophy.
• Functional connectivity measures show promise as early diagnostic biomarkers for AD.
• This study highlights the potential of advanced neuroimaging analysis for improved AD detection and monitoring.