You know that moment when you notice your mind wandering? Maybe you’re reading a book and notice that you’ve been scanning the page but thinking unrelated thoughts? This project will develop an innovative tool to model when and how your brain notices, i.e. “meta-awareness” (MA). We have some idea of neural-correlates of MA (the salience network), but we do not understand the time-course of MA. No scientific tools that measure MA exist, and MA is tricky to measure because you’d have to have MA to report losing it, which is a catch-22. This project proposes a new tool to measure MA that will result in models that detect not only MA, but the whole attention cycle: focusing, mind-wandering, MA, and refocusing. Two studies will develop and deliver a measurement tool, a behavioral model of MA, and an advanced neurophysiological model of the awareness cycle. Behavioral and fMRI studies are proposed. Machine- and deep learning will be used for analysis. Inattention causes practical problems (e.g. car-accidents) and MA deficits underlie several psychopathologies (e.g. depression). The models developed here will scaffold practical applications (e.g. apps) and clinical innovation (e.g. MA training). Our models will vitally inform views on the nature of human awareness.