Limbic Risk Stratification Framework: A Coordinated AmygdalaHippocampus Network Model for Early Alzheimer's Detection

Abstract & Rationale:This framework presents a staged neurodegenerative risk model based on longitudinal MRI analysis of 696 participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI). While hippocampal atrophy is the traditional gold-standard biomarker for Alzheimer’s Disease (AD), this model highlights the amygdala as a sentinel node in the early neurodegenerative cascade.Key Findings:Temporal Sequence: Amygdala atrophy (defined as a ≥5% longitudinal decline) preceded clinical conversion in 55% of analyzed cases.Network Coordination: The prognostic signal of the amygdala is closely linked to hippocampal integrity (p = 0.092 after adjustment), providing empirical evidence for a Coordinated Limbic Network Failure model.Clinical Utility: The integrated table categorizes risk from Stage 0 (Normal) to Stage 4 (Advanced), mapping neuroimaging findings to specific preventive strategies, including lifestyle bio-optimization and metabolic protection.This model shifts the diagnostic paradigm from isolated structural atrophy to Network Neuroscience, identifying a critical "window of opportunity" for early intervention.