Your mind wanders weakly, your mind wanders deeply: Objective measures reveal mindless reading at different levels

► It is possible to predict states of mindless reading from eye movements. ► As mind wandering reduces external attention cognitive processing is decoupled. ► We propose the levels-of-inattention hypothesis postulating graded decoupling. ► We developed the SAST to measure decoupling using psychophysics of error detection. ► Results on different levels of mindless reading support levels of inattention.