Average aging is associated with a gradual decline of memory capacity. SuperAgers are humans over age 80 who show exceptional episodic memory at least as good as individuals 20-30 years their junior. This study investigated whether neuronal integrity in entorhinal cortex (ERC), an area critical for memory and selectively vulnerable to neurofibrillary degeneration, differentiated SuperAgers from cognitively-healthy younger individuals, cognitively-average peers (“Normal Elderly”), and individuals with amnestic Mild Cognitive Impairment (aMCI). Postmortem sections of the ERC were stained with cresyl violet to visualize neurons, and immunostained with PHF-1 to visualize neurofibrillary tangles. The cross-sectional area (i.e., size) of layer II and layer III/V ERC neurons were quantified. Two-thirds of total participants were female. Unbiased stereology was employed to quantitate tangles in a subgroup of SuperAgers and Normal Elderly. Linear mixed-effect models were used to determine differences across groups....