Working memory has been an important concept for psychological science for over 30 years, taking its modern form and inspiration from the work of Baddeley and Hitch (1974). Whilst our collective understanding of the term has evolved and diversified, we show that working memory still remains highly relevant to issues in cognition; contemporary research indicates how both theoretical models and the concept of working memory has much to offer the research discipline. We introduce five empirical studies for this special issue on working memory and show how each paper contributes to the broader understanding of cognition. More specifically these papers constrain ongoing debates about the domain-specific nature of short-term and working memory, the binding of different types of representations, the nature of executive control, and the role of working memory in action control. We attempt to place these four research themes under a larger research framework into which the five experimental articles are located.

View full abstract

We tested the hypothesis that olfactory information can be temporarily retained in a modality-specific short-term memory system. The results of two experiments using short-term memory tasks supported this hypothesis. Experiment 1 showed an effect of concurrent odour memory on digit recall that was equivalent to the effect of concurrent visual memory and smaller than that of concurrent verbal memory. Experiment 2 showed a detrimental effect of concurrent odour memory on odour recognition, and no effect of concurrent verbal and visual memory tasks. Based on these findings, and on published evidence for rehearsal and imagery of olfactory information, we tentatively conclude that there is a subsystem in working memory dedicated to temporary maintenance of olfactory information.

View full abstract

Two proposed factors affecting visual working memory maintenance were explored. By means of the dynamic visual noise technique (DVN, Quinn & McConnell, 1996), perceptual structural complexity, and dynamic movement of irrelevant visual information, have been shown to affect memory for subject-generated images, but not for visual inputs. Three experiments manipulated the level of perceptual complexitity (standard DVN vs. dynamic figures, and dynamic vs. static characteristics) of an interfering display, while performing a visual recognition short-term memory task employing novel polygons. Results replicated the lack of standard DVN effect on memory for visual inputs, but showed that an irrelevant visual figure, more structured than standard DVN, decreased performance. Polygon recognition was affected by a static irrelevant visual figure, but was significantly lower when it was dynamic. Interference based on perceptual factors, and spatial displacements of incoming inputs, are discussed within the context of visual working memory mechanisms and architecture.

View full abstract

The picture superiority effect in spatial working memory refers to a better retention of the locations of objects or images compared to locations of words. The present research suggests that such effect extends to situations in which the items are serially presented. Participants were required to reproduce different series of icons or words either according to the original spatial configuration, or following the temporal sequence of presentation, or both these aspects together. Overall, both memory for spatial locations and for the temporal order were better with icons than with words. Furthermore, performance decreased when both the features had to be simultaneously retained, suggesting that we do not automatically integrate spatial and temporal information, but such binding requires attentional processing.

View full abstract

This study examined the “inefficient inhibition hypothesis” (IIH; Bjorklund & Harnishfeger, 1990; Wilson & Kipp, 1998) in three groups: children with specific language impairment (SLI), age-matched and language-matched controls. The IIH suggests that individuals with efficient inhibition skills perform better on working memory tasks because they are able to keep out irrelevant information from working memory. Children with SLI show processing capacity limitations. This study examined whether the working memory limitations are impacted by inhibition problems in this population. Working memory capacity was measured with a listening span task and children’s inhibition errors were categorized. These errors reflected either immediate or delayed inhibition problems and they indicated either contextual distractions or perseverations. Children with SLI produced more inhibition errors than their peers in most categories. The results show an association between inhibition control and working memory capacity, but the direction of causality is not clear.

View full abstract

This paper considers the effect of articulatory suppression on a number-size consistency task to investigate the involvement of the phonological loop in situations involving potential interferences from task-irrelevant stimulus attributes. Participants were shown pairs of digits varying in numerical and physical sizes, and they were required to decide which digit was larger numerically or physically in the numerical-size and physical-size judgment tasks, respectively. Participants in the continuous-task group only performed the numerical-size judgment task. On the other hand, participants in the change-task group practiced the physical-size judgment task and then performed the numerical-size judgment task. The results showed that articulatory suppression had a negative effect on reaction time in the numerical-size judgment task only in the change-task group. This suggests that the phonological loop provides a useful aid for the control of action when participants are faced with interference in a difficult situation of maintaining the task goal.

View full abstract