Brain scans of 86 cognitively normal older adults revealed distinct connectivity patterns in those carrying APOE4 genes or showing early Alzheimer's pathology. APOE4 carriers displayed reduced local brain connectivity in frontal regions but increased distant connections in motor and attention areas. Similarly, individuals with elevated neurofilament light chain—a blood marker of neurodegeneration—showed weakened local connections in the insula and cingulate cortex alongside strengthened distant connections in memory-related regions. These altered connectivity patterns correlated with poorer cognitive performance across multiple domains. The findings suggest the brain may initially compensate for early pathological changes by recruiting distant regions, but this strategy appears counterproductive for maintaining cognitive function. This research advances understanding of how Alzheimer's risk factors reshape brain networks years before clinical symptoms emerge. The ability to detect these changes through brain imaging and blood tests could enable earlier intervention strategies. However, as an unreviewed preprint, these results require peer validation. The relatively small sample size also limits generalizability, though the comprehensive approach combining genetics, blood biomarkers, and advanced brain imaging represents a significant methodological advancement in preclinical Alzheimer's research.