Luck and Vogel (1997) showed that the storage capacity of visual working memory is about four objects and that this capacity does not depend on the number of features making up the objects. Thus, visual working memory seems to process integrated objects rather than individual features, just as verbal working memory handles higher-order "chunks" instead of individual features or letters. In this article, we present a model based on synchronization and desynchronization of reverberatory neural assemblies, which can parsimoniously account for both the limited capacity of visual working memory, and for the temporary binding of multiple assemblies into a single pattern. A critical capacity of about three to four independent patterns showed up in our simulations, consistent with the results of Luck and Vogel. The same desynchronizing mechanism optimizing phase segregation between assemblies coding for separate features or multifeature objects poses a limit to the number of oscillatory reverberations. We show how retention of multiple features as visual chunks (feature conjunctions or objects) in terms of synchronized reverberatory assemblies may be achieved with and without long-term memory guidance.

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People can evaluate the quality of their memories by giving a confidence judgement concerning the perceived accuracy of what is recalled or recognised. Even when people strive for accuracy and claim great confidence they may, however, not remember what actually happened. Both accuracy and confidence can be affected by various factors. In this study, we investigated the effects of retention interval (either 1, 3 or 5 weeks delay before first testing) and of repeated questioning (initial recall after 1 week, repeated after 3 and 5 weeks) on accuracy and confidence of recall of a naturalistic videotaped event. Longer retention intervals before initial testing resulted in lower accuracy and lower confidence scores. Repeated recall, however, had little effect on accuracy and confidence. Relatively high accuracy-confidence correlations were found in all delay and repetition conditions. Practical implications of these findings for questioning eyewitnesses are discussed.

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If 2 words are presented successively within 500 ms, subjects often miss the 2nd word. This attentional blink reflects a limited capacity to attend to incoming information. Memory effects were studied for words that fell within an attentional blink. Unrelated words were presented in a modified rapid serial visual presentation task at varying stimulus-onset asynchronies, and attention was systematically manipulated. Subsequently, recognition, repetition priming, and semantic priming were measured separately in 3 experiments. Unidentified words showed no recognition and no repetition priming. However, blinked (i.e., unidentified) words did produce semantic priming in related words. When, for instance, ring was blinked, it was easier to subsequently identify wedding than apple. In contrast, when the blinked word itself was presented again, it was not easier to identify than an unrelated word. Possible interpretations of this paradoxical finding are discussed.