Hein, L. & Oberauer, K.
Department of Psychology (Cognitive Psychology Unit), University of Zurich, Switzerland
The study investigates how the single-item focus of attention (foa) in working memory can be distracted. The foa is assumed to hold on to the last item processed, such that sequential operations on the same item are faster than switches to a different item in working memory. To explore whether the foa can be detracted from an item by perceptual input, we used an interruption paradigm. We combined a sequential arithmetic memory-updating task with rare interruptions by perceptual stimuli, to which an immediate choice response was required. If the last item processed before the interruption remains in the foa after the interruption, object-repetition benefits should remain when updating is resumed after the interruption. Results indicate that memory items do not remain in the foa after interruptions by responses to perceptual stimuli. Interruptions by infrequent unfilled time intervals of the same duration as the responses to the interruption task had the same effect. However, repetition benefits remained when unfilled intervals were interspersed more frequently and hence, were not surprising. We conclude that the foa can be detracted by surprise, as indicated by the disappearance of repetition benefits after infrequent events, but not when the same events occur frequently.