Abstract

Popular models of visual working memory assume that working memory is limited by a constant resource, which is conceived as either quantized (as in slot models) or infinitely divisible. These models share the assumption that the probability and quality of retrieval depends on the resource assigned to a representation in working memory. I will present an alternative model that incorporates the principles of general theories of memory: Retrieval is cue-based, and performance is limited by interference arising from several sources. Representations compete for retrieval according to the amount of activation each of them receives at retrieval. Activation arises from three sources: Persistent activation of representations of recently encoded items, activation from the retrieval cue, and background noise. One item is held in the focus of attention; this item is represented with higher precision, and suffers less interference from competing items and from noise. So far the model explains set-size effects as well as pre- and retro-cue effects in the continuous-reproduction paradigm. Ongoing work aims at extending the model to recognition/change detection; depending on how much progress we make until October I will present some of that work as well.

Biosketch

I have studied Psychology at Free University Berlin, and received my PhD from University of Heidelberg in 1995. After many productive years in Reinhold Kliegl’s lab at the University of Potsdam I held a Chair at the University of Bristol (2005-2009). Since 2009 I am Professor of Cognitive Psychology at the University of Zurich. My team’s research focuses on the limits of human cognitive abilities, and in particular the capacity limits of working memory and attention. In essence, we ask: Why are people not smarter than they are? We study these questions through a combination of behavioral experiments, individual-differences studies, and computational modeling.