Intrinsic functional connectivity strength of SuperAgers in the default mode and salience networks: Insights from ADNI.

ABSTRACT

There exists a group of older individuals who appear to be resistant to age-related memory decline. These "SuperAgers" have been shown to demonstrate preservation of cortical thickness and functional connectivity strength across the cortex which positively correlates with memory performance. Over the last decade, roughly 30 articles have been published regarding SuperAgers; however, to our knowledge, no replications of these studies have been published. The current study sought to conceptually replicate Zhang and colleagues' (2020) findings that SuperAgers demonstrate stronger intrinsic functional connectivity within the default mode (DMN) and salience networks (SN), and that connectivity strength within these networks correlates with memory performance. We identified 20 SuperAgers and 20 matched Normal Agers in the control cohort of the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. We compared the functional connectivity strength of the DMN and SN between these groups, and used the Rey Auditory Verbal Learning Test (RAVLT) to evaluate correlations between functional connectivity and memory performance. Our results did not replicate Zhang and colleagues' (2020) results, as we found negligible differences between SuperAgers and Normal Agers in the DMN and SN, and no significant correlations between functional connectivity and memory performance after accounting for multiple comparisons. More replications are needed to confirm existing work. In addition, more research with larger SuperAger samples and more consistent definitions of SuperAging is needed, so that we can better understand this remarkable group of older adults.