OS_15. Working memory
Saturday, October 01st, 2011 [10:50 - 11:50]
OS_15.1 - Word-frequency effect on working memory task
Camos, V. 1 & Mora, G. 2
1 Universite de Fribourg
2 Universite de Bourgogne
Many studies have shown an advantage for high-frequency words in various language and memory tasks. Surprisingly, only one study reported a word-frequency effect in a working memory task (Engle et al., 1990). In the present study, we evaluated the word-frequency effect in complex span task in which the pace of a concurrent task was manipulated. By slowing down the pace of a location judgement task, attention could be switched to maintenance activities for a longer time and recall should be better (Barrouillet et al., 2007). As already reported in immediate serial recall tasks, the advantage for recalling high-frequency words increased across serial positions. This finding is congruent with the redintegration hypothesis, which stated that long-term knowledge helps at reconstructing degraded memory traces at recall (Hulme et al., 1997). Although the pace effect was replicated, it did not interact neither with the word-frequency effect nor with the interaction between frequency and serial position. This pattern of results favours the idea that pace and word-frequency affect distinct steps of processing, the maintenance during the concurrent task and the reconstruction at recall respectively.
OS_15.2 - Attention modulates spatial and temporal encoding in auditory and visual working memory
Delogu, F. , Nijboer, T. & Postma, A.
Experimental Psychology, Helmholtz Institute, Utrecht University, the Netherlands
Information about where and when events happened seem naturally linked to each other, but only few studies have investigated if and how they become associated in working memory. We tested whether the location of item and their temporal order are jointly or independently encoded. We also verified if spatio-temporal interactions change according to the sensory modality of items. In two experiments, participants memorized sequences of five environmental sounds (exp.1) and pictures (exp.2) originating from five different locations. They were asked to recall either their position or temporal order. Attention during encoding was manipulated by contrasting blocks containing different percentages of spatial and temporal trials. Results indicate that temporal and spatial encoding is more effective when attention is focused on the target dimension. Interesting differences between modalities also emerged. In the auditory modality, while temporal order recall was linearly affected by the simultaneous encoding of item location, position recall was mostly unaffected by a concurrent memory load. In vision, the recall of both temporal and spatial information was strongly affected by attention. We conclude that temporal order and spatial encoding are conducted by separate mechanisms and that the strength of their association is modulated by the modality of the input.
OS_15.3 - The role of short term consolidation in working memory updating
Kessler, Y. & Guy, M.
Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
An updating variant of Jolicoeur & Dell’Acqua’s (1998) paradigm was used to examine the role of short-term consolidation in working memory (WM) updating. In each trial, a set of letters appeared on the screen and the participants had to update their WM with the new information. The number of updated items was varied between one trial and another. After several updating trials a tone appeared, and the participants had to judge the tone pitch, and then to recall the last stimulus set that was presented. Stimulus onset interval (SOA) between the last updating trial and the tone was manipulated. Reaction times (RTs) for the tone judgment served to measure the updating duration. When the entire WM set was presented in each trial, RT for the updating conditions decreased with SOA within a given set-size, but was insensitive to the number of changed items. When only the updated items were presented in each trial, RT was sensitive both to the number of changed items and the total set-size. The results are discussed in relation to local and global WM updating processes (Kessler & Meiran, 2008), and suggest a role of short term consolidation in global updating.