The Role of Semantic Representations in Verbal Working Memory

Two main mechanisms, articulatory rehearsal and attentional refreshing, are argued to be involved in the maintenance of verbal information in working memory (WM). While converging research has suggested that rehearsal promotes the phonological representations of memoranda in working memory, little is known about the representations that refreshing may promote. Not only would examining this question address this gap in the literature, but the investigation has profound implications for different theoretical proposals of how refreshing functions and on the relationships between WM and long-term memory (LTM). Accordingly, we tested predictions from five models regarding how refreshing may moderate the semantic representation of memoranda in verbal WM. This series of four experiments presented a cue word that was either semantically or phonologically related to a target during the recall phase of a complex span task. Experiment 1 established the benefit of semantic over phonological retrieval cues, and Experiment 2 established that this semantic benefit was specific to a refreshing- rather than a rehearsal-based maintenance strategy. Finally, we showed that this semantic benefit did not vary with the cognitive load of the concurrent task (Experiments 3 and 4) or the intention to learn the memoranda (Experiment 4). These results indicate that cue-based retrieval from episodic LTM may strongly contribute to semantic processing effects in WM recall, but this influence of episodic LTM is independent of the function of refreshing to reactivate memory traces. Accordingly, these results have strong implications for the functioning of refreshing and the links between WM and LTM

Inner speech sustains predictable task switching: direct evidence in adults

It has been proposed that inner speech supports task selection in task-switching studies, especially when the need for endogenous control is increased. This has been established through the suppression of inner speech in cognitive-flexibility tasks that leads to poorer performance. The aim of this study is to quantify the role of inner speech in a flexibility task by using surface laryngeal electromyography, which, contrary to previous studies, enables participants to freely verbalise the tasks. We manipulated endogenous and exogenous flexibility in a mathematical switching task paradigm. Experiment 1 shows that inner speech acts as a support for switching and is recruited more often when the tasks are of an endogenous type. The main result of Experiment 2 that language is recruited more for the mixing cost than for the switch cost (regardless of the endogenous factor) extends past findings obtained through articulatory suppression

Faces presenting sadness enhance self-control abilities in gifted adolescents.

Self-regulation skills refer to processes allowing emotional and cognitive adaptation of the individual. Some gifted adolescents are known for their imbalance between high intellectual abilities and low emotional skills. Thus, this study aimed at examining the interplay between emotion and cognition in gifted and non-gifted adolescents. A stop-signal task, a response inhibition task including neutral, happy, or sad faces as signal triggering inhibition, was administered to 19 gifted and 20 typically developing male adolescents (12-18 years old). Gifted adolescents showed lower response inhibition abilities than non-gifted adolescents in the neutral and happy face conditions. Sad faces in gifted adolescents were associated with higher response inhibition compared to happy condition. In typically developing adolescents, emotional information (happy or sad faces) was related to lower response inhibition compared to neutral face condition. This study highlights that gifted adolescents present different self-regulation skills than their typically developing peers. Statement of contribution What is already known on this subject? Some gifted adolescents present higher intellectual abilities alongside with lower socio-emotional skills. Self-regulation skills refer to processes allowing emotional and cognitive adaptation. Self-regulation skills might help to understand gifted adolescents, but remain scarcely studied. What does this study adds? Task-relevant emotional information impaired cognitive control in typically developing adolescents. Gifted adolescents are able to use sad faces to enhance their cognitive control abilities

Searching for serial refreshing in working memory:Using response times to track the content of the focus of attention over time

One popular idea is that, to support maintenance of a set of elements over brief periods of time, the focus of attention rotates among the different elements thereby serially refreshing the content of Working Memory (WM). In the research reported here, probe letters were presented between to-be-remembered letters. Response times to these probes were used to infer the status of the different items in WM. If the focus of attention cycles from one item to the next, its content should be different at different points in time and this should be reflected in a change in the response time patterns over time. Across a set of four experiments, we demonstrate a striking pattern of invariance in the response time patterns over time, suggesting that either the content of the focus of attention did not change over time or that response times cannot be used to infer the content of the focus of attention. We discuss how this pattern constrains models of WM, attention, and human information processing

Disentangling the respective contribution of task selection and task execution in self-directed cognitive control development

peer reviewedTask selection and task execution are key constructs in cognitive control development. Yet, little is known about how separable they are and how each contributes to task switching performance. Here, 60 4- to 5-year olds, 60 7- to 8-year olds, and 60 10- to 11-year olds children completed the double registration procedure, which dissociates these two processes. Task selection yielded both mixing and switch costs, especially in younger children, and task execution mostly yielded switch costs at all ages, suggesting that task selection is costlier than task execution. Moreover, both task selection and execution varied with task self-directedness (i.e., to what extent the task is driven by external aids) demands. Whereas task selection and task execution are dissociated regarding performance costs, they nevertheless both contribute to self-directed control

Reduced bone loss is associated with reduced mortality risk in subjects exposed to nitrogen bisphosphonates: A mediation analysis

Bisphosphonates, potent anti-resorptive agents, have been found to be associated with mortality reduction. Accelerated bone loss is, in itself, an independent predictor of mortality risk, but the relationship between bisphosphonates, bone loss, and mortality is unknown. This study aimed to determine whether the association between bisphosphonates and mortality is mediated by a reduction in the rate of bone loss. Participants from the population‐based Canadian Multicentre Osteoporosis Study were followed prospectively between1996 and 2011. Comorbidities and lifestyle factors were collected at baseline and bone mineral density (BMD) at baseline and at years 3 (for those aged 40 to 60 years), 5, and 10. Rate of bone loss was calculated using linear regression. Information on medication use was obtained yearly. Bisphosphonate users grouped into nitrogen bisphosphonates (nBP; alendronate or risedronate) and etidronate and non‐users (NoRx) were matched by propensity score, including all baseline factors as well as time of treatment. Cox’s proportional hazards models, unadjusted and adjusted for annual rate of bone loss, were used to determine the association between nBP and etidronate versus NoRx. For the treatment groups with significant mortality risk reduction, the percent of mortality reduction mediated by a reduction in the rate of bone loss was estimated using a causal mediation analysis. There were 271 pairs of nBP and matched NoRx and 327 pairs of etidronate and matched NoRx. nBP but not etidronate use was associated with significant mortality risk reduction (hazard ratios [HR]=0.61 [95% confidenceinterval0.39–0.96]and1.35[95%CI0.86–2.11] for nBP and etidronate, respectively). Rapid bone loss was associated with more than2‐fold increased mortality risk compared with no loss. Mediation analysis indicated that39% (95%CI7%–84%) of the nBP association with mortality was related to a reduction in the rate of bone loss. This finding provides an insight into the mechanism of the relationship between nBP and survival benefit in osteoporotic patients

Range dependent processing of visual numerosity: similarities across vision and haptics

‘Subitizing’ refers to fast and accurate judgement of small numerosities, whereas for larger numerosities either counting or estimation are used. Counting is slow and precise, whereas estimation is fast but imprecise. In this study consisting of five experiments we investigated if and how the numerosity judgement process is affected by the relative spacing between the presented numerosities. To this end we let subjects judge the number of dots presented on a screen and recorded their response times. Our results show that subjects switch from counting to estimation if the relative differences between subsequent numerosities are large (a factor of 2), but that numerosity judgement in the subitizing range was still faster. We also show this fast performance for small numerosities only occurred when numerosity information is present. This indicates this is typical for number processing and not magnitude estimation in general. Furthermore, comparison with a previous haptic study suggests similar processing in numerosity judgement through haptics and vision

Cross-domain interference costs during concurrent verbal and spatial serial memory tasks are asymmetric

Some evidence suggests that memory for serial order is domain-general. Evidence also points to asymmetries in interference between verbal and visual-spatial tasks. We confirm that concurrently remembering verbal and spatial serial lists provokes substantial interference compared with remembering a single list, but we further investigate the impact of this interference throughout the serial position curve, where asymmetries are indeed apparent. A concurrent verbal order memory task affects spatial memory performance throughout the serial positions of the list, but performing a spatial order task affects memory for the verbal serial list only for early list items; in the verbal task only, the final items are unaffected by a concurrent task. Adding suffixes eliminates this asymmetry, resulting in impairment throughout the list for both tasks. These results suggest that domain-general working memory resources may be supplemented with resources specific to the verbal domain, but perhaps not with equivalent spatial resources