Tracking continuities in the flanker task: From continuous flow to movement trajectories

Since its introduction nearly a half century ago, the Eriksen flanker task has prompted multiple theoretical and methodological advancements in the study of attention and control. Early research with the task inspired the continuous flow model of information processing, which in turn prompted researchers to investigate the dynamics of response competition using continuous behavioral measures. In recent years, the use of such measures in psychological research has increased dramatically as hand-tracking techniques have become more widely accessible. The current article highlights commonly overlooked links between Eriksen and colleagues' pioneering research investigating the continuous flow model and recent hand-tracking research investigating the dynamics of attention and control. After providing an overview of two hand-tracking techniques frequently used in psychological research, we review a series of recent studies that have used these techniques to investigate how the processes underlying attention and control (a) unfold over the course of a response (within-trial dynamics), (b) are impacted by recent experience (cross-trial dynamics), and (c) contribute to age-related changes observed across the life span (developmental dynamics). In addition to highlighting the central role that the flanker task has played in advancing psychological research and theory, this review underscores the advantages of collecting continuous behavioral measures, both in Eriksen's seminal work and in contemporary hand-tracking studies.