Implicit Working Memory: Implications for Assessment and Treatment

Working memory (WM) impacts a gamut of cognitive abilities, but implicit WM is typically not considered in assessment or treatment, which may explain the variability of results in reviews of WM training. The role of implicit WM in adaptive behavior is reviewed. All we do is action based. Explicit WM plays a major role when we are required to "think"; that is, when we apply previously learned perception-action linkages in new ways to unique situations. Implicit WM is involved in the automation of behavior, which occurs through interaction with cortical and subcortical systems that guide sensory-motor anticipation and the prediction of reward. This article reviews evidence that implicit WM interacts with cortical-cerebellar and cortical-basal ganglia connections to form perception-action linkages. The cerebellum forms an internal model of cortical WM, corrects the content of this internal model, and then projects the improved representation back to the cortex, where it is retained for future use. The basal ganglia also form an anticipatory system, controlling cortical access to WM by allowing or restricting the information that is released based on the probability of reward. This framework is applied to the assessment and treatment of individuals with WM deficits. The ability to automate behavior can be assessed through repeated trials of existing testing instruments, such as the Trails B and Stroop tasks. Application of skill learning emphasizing automation as an end goal offers a model for the development of new types of WM training.