In this issue of JAMA Neurology, Hohman et al1 provide new insights into a biomarker related to cognitive performance in advanced age. They report that elevated levels of vascular endothelial growth factor (VEGF) in cerebrospinal fluid (CSF) are associated with improved hippocampal volume, episodic memory, and executive function. Moreover, statistical analyses were applied to test how the CSF levels of β-amyloid 42 and tau may interact with CSF VEGF levels to help predict neurocognitive factors in their sampled research participants. Hohman and colleagues report on analyses from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database, which comprises neuroimaging, CSF, and neurocognitive longitudinal data on 279 patients, regrettably without corresponding autopsy data.