Souza da Silva, A. , Oberauer, K. , Gade, M. & Druey, M.
University of Zurich
Oberauer (2009) distinguishes two working memory (WM) sub-systems: The declarative WM provides information input (memory-sets) for processing; whereas the procedural WM provides access to the processing operations themselves (task-sets). The present study tested the assumption that these sub-systems select representations in analogous ways. Participants selected a memory-list and a digit within the list (declarative representations). They selected a task-set to be applied to the digit, and a response within that task-set (procedural representations). The number of lists (one, two, or three) and the number of tasks (one, two, or three) to be switched between were manipulated independently. Switching between lists and switching between tasks produced time costs (list-switch and task-switch costs, respectively). List-switch costs increased as a function of the number of lists (two versus three); whereas task-switch costs were not affected by the number of tasks to be switched between. Increasing the number of lists also affected task-switch costs, indicating some degree of interaction between the sub-systems. Furthermore, analogous patterns of list-mixing and task-mixing costs were observed. These findings support the hypothesis of analogous, but not completely independent, WM sub-systems.