Attended and non-attended states in working memory: Accessing categorized structures

Following several recent approaches, working memory is argued to consist of a subset of representations that are within the scope of active processing and a larger set of recently activated, but non-attended representations. A response-signal speed-accuracy tradeoff (SAT) and comple mentary reaction time variant of a probe recognition task were used to measure the retrieval of categorized material from working memory. In SAT, two distinct retrieval speeds were found: A fast rate for items from the last studied category and a slower rate common to all items from other categories in the list. This difference in retrieval speed was evident in the shapes of the reaction time distributions. The faster retrieval speed for items from the last category is argued to reflect a matching process in which the recognition probe is rapidly compared to the current contents of awareness. (C) 1998 Academic Press.