Types Of Working Memory Tasks Research Articles

Relation between working memory and implicit learning in the contextual cueing paradigm

ABSTRACT We examined whether implicit learning (IL) in visual search involves working memory (WM). IL was examined in a contextual cueing paradigm in which visual search performance is facilitated by implicitly learned spatial associations (the contextual cueing effect [CCE]; Chun, M. M., & Jiang, Y. (1998). Contextual cueing: Implicit learning and memory of visual context guides spatial attention. Cognitive Psychology, 36(1), 28–71. https://doi.org/10.1006/cogp.1998.0681). IL and WM tasks were performed concurrently. Participants were tested in one of three types of WM tasks testing memory of (1) object colour, (2) relation between object shape and colour and (3) relation between object location and identity. Results showed that the CCE remained relatively intact regardless of the type of WM task. These results fail to support the idea that IL and working memory are related.

No Spearman’s Law of Diminishing Returns for the working memory and intelligence relationship

AbstractSpearman’s Law of Diminishing Returns (SLODR) holds that correlation between general (g)/fluid (Gf) intelligence factor and other cognitive abilities weakens with increasing ability level. Thus, cognitive processing in low ability people is most strongly saturated by g/Gf, whereas processing in high ability people depends less on g/Gf. Numerous studies demonstrated that low g is more strongly correlated with crystallized intelligence/creativity/processing speed than is high g, however no study tested an analogous effect in the case of working memory (WM). Our aim was to investigate SLODR for the relationship between Gf and WM capacity, using a large data set from our own previous studies. We tested alternative regression models separately for three types of WM tasks that tapped short-term memory storage, attention control, and relational integration, respectively. No significant SLODR effect was found for any of these tasks. Each task shared with Gf virtually the same amount of variance in the case of low- and high-ability people. This result suggests that Gf and WM rely on one and the same (neuro)cognitive mechanism.

Mental subtraction and multiplication recruit both phonological and visuospatial resources: evidence from a symmetric dual-task design.

Previous studies pointed out a selective interaction between different working memory subsystems (i.e., phonological and visuospatial) and arithmetic operations (i.e., multiplication and subtraction). This was interpreted to support the idea that multiplication and subtraction predominantly rely on a phonologically or spatially organized number code, respectively. Here, we investigated this idea in two groups (multiplication and subtraction group) using a dual-task paradigm. Going beyond previous studies, we carefully controlled and balanced the difficulty of both working memory and calculation tasks within and across participants. This allowed us to test the reciprocal impact of calculations on working memory. We observed no selective interaction between different working memory subsystems and arithmetic operations. Instead, both types of arithmetic operations were impaired by both types of concurrent working memory tasks. Likewise, both types of working memory tasks were impaired by both types of concurrent arithmetic. Our findings suggest that multiplication and subtraction depend on both phonological and visuospatial codes and highlight the importance of balancing task demands within and between participants in the context of dual-task studies.

Functional differentiation within the monkey cortex as revealed by near-infrared spectroscopy

AbstractThe role of prefrontal cortex in working memory (WM) is well established. However, questions remain regarding the topography and “domain-specific differentiation” of different types of information processing in the cortex. While it has been theorized that dorsolateral (DPFC) and ventrolateral (VPFC) prefrontal cortex preferentially process spatial and object WM, respectively, both electrophysiological evidence in the monkey and neuroimaging in the human have largely failed to demonstrate such regional differentiation. In this study we use near-infrared spectroscopy (NIRS) to detect functional changes, across relatively large cortical cell populations, simultaneously from prefrontal and posterior parietal cortices. Imaging data were recorded from a Rhesus macaque performing two types of WM tasks: a spatial task in which the animal had to retain the spatial position of a visual stimulus, and a non-spatial task where he had to retain its color (red or green) during a 20s delay. During performance of the spatial WM task, cerebral activation trends were found in which DPFC exhibited stronger activation than did the VPFC, and posterior parietal cortex maintained higher delay activation than did frontal regions. These differences were less pronounced during performance of the non-spatial task. Additionally, incorrect trials generally elicited lower activations during the delay period than did trials ending with a correct response. Furthermore, NIRS data collected during the performance of a haptic WM task also appear to exhibit inter-regional differences in delay activation. The data thus suggest the presence of preferential cognitive processing between and within posterior and frontal cortical regions.

Evidence for multiple manipulation processes in prefrontal cortex

The prefrontal cortex (PFC) is known to subserve working memory (WM) processes. Brain imaging studies of WM using delayed response tasks (DRTs) have shown memory-load-dependent activation increases in dorsal prefrontal cortex (PFC) regions. These activation increases are believed to reflect manipulation of to-be-remembered information in the service of memory-consolidation. This speculation has been based on observations of similar activation increases in tasks that overtly require manipulation by instructing participants to reorder to-be-remembered list items. In this study, we tested the assumption of functional equivalence between these two types of WM tasks. Participants performed a DRT under two conditions with memory loads ranging from 3 to 6 letters. In an “item-order” condition, participants were required to remember letters in the order in which they were presented. In a “reordering” condition, participants were required to remember the letters in alphabetical order. Load-related activation increases were observed during the encoding and maintenance periods of the order maintenance condition, whereas load-related activation decreases were observed in the same periods of the reordering condition. These results suggest that (1) the neural substrates associated with long-list retention and those associated with reordering are not equivalent, (2) cognitive processes associated with long-list retention may be more closely approximated by item-order maintenance than by reordering, and (3) multiple forms of WM manipulation are dissociable on the basis of fMRI data.

Influence of a visuo-spatial, verbal and central executive working memory task on postural control.

In this study, participants were required to perform different working memory (WM) tasks (a verbal task, a visuo-spatial task with two levels of difficulty and a central executive task) under different challenges to postural control (sitting, shoulder width stance and tandem stance). When a WM task was added, changes in postural sway were characterized by an increase in frequency and decrease in amplitude of sway indicating a tighter control. We found no changes in postural control between the different types of WM tasks, which might support a general capacity limitation hypothesis. However, no changes were found in performance of the WM when postural stance was modified and no changes were found in postural sway, when the difficulty level of the visuo-spatial task was modified. Consequently, the results seem to indicate that the addition of a WM task, regardless of task type or task difficulty, forces the central nervous system to choose a tighter control strategy.