JMIR Publications

ABSTRACT

A body of research suggests that within-person variability in cognitive performance may be a sensitive indicator of impairment, compared to scores obtained at one point in time. In this review, we describe the manifestation of within-person variability in healthy populations and its predictive power in clinical populations. To better understand potential factors that give rise to this variability, we explore how moderators at both the internal (mood, motivation) and external/contextual (time of day, surrounding noise, activity) levels affect cognitive performance, and we may capitalize on advancements in mobile technology to capture such information. Smartphone-based assessment may serve as an optimal method for capturing individual cognitive variability in real-world contexts. We propose that through the use of mobile assessment we have the opportunity to combine multiple sources of contextual and cognitive data to provide individualized digital signatures that could improve prediction of meaningful clinical outcomes.