Task manipulation effects on the relationship between working memory capacity and go/no-go performance

Seemingly minor task manipulations can have large and sometimes unpredicted effects on task performance. Despite this, single tasks are typical in both research and assessment applications. This series of experiments aims to systematically investigate the differences between various perceptual and semantic versions of go/no-go tasks and their relationships with working memory capacity (WMC) with the goal of determining the cause of inconsistencies in the literature. Because these versions of the go/no-go have not previously been systematically studied, the first experiment does so. After determining which performance differences exist based on versions of both task and decision, and noting that these performance measures did not differ in the critical relationship with WMC, other patterns in the literature were examined. Experiment 2 used these patterns to determine a potential cause of the differences in WMC relationships with go/no-go outcome measures, inter-stimulus interval (ISI). Manipulating ISI influenced the relationships with WMC, though the decision type still had effects above and beyond that of the ISI

Titrating Cognitive Control: Trial-Level Dynamic Use of Proactive and Reactive Cognitive Control

Cognitive control is accomplished by a set of higher-order cognitive processes that are recruited to aid in the completion of various tasks. A popular proposed mechanism is the Dual Mechanisms of Control (Braver, Gray, & Burgess, 2007), proposing proactive and reactive mechanisms. While neuroscience studies provide evidence that these are two distinct processes, it remains unclear whether the processes are competing, or whether they can be used together. That is, are the two processes able to both be enacted to some degree? Further, whether these mechanisms can be titrated to produce a gradient-like use of control on a trial-level basis is unknown. These are the two primary pursuits of this dissertation. Experiment 1 shows the titrated pattern of control use, indicating (a) sensitivity to task demands, and (b) dynamic use of proactive and reactive control at the trial level, in a new task. Further, a novel contribution is the observation of ability to titrate the use of control. Additional experiments relate performance on this task to working memory (Experiment 2), replicate the findings in an online format (Experiment 3), and differentiate performance from distance effects commonly seen in relative judgment tasks (Experiment 4). This work has implications for the understanding of how cognitive control functions and how dynamically the use of these mechanisms can be adjusted

Advancing the understanding of individual differences in attentional control: Theoretical, methodological, and analytical considerations

Attentional control as an ability to regulate information processing during goal-directed behavior is critical to many theories of human cognition and thought to predict a large range of everyday behaviors. However, in recent years, failures to reliably assess individual differences in attentional control have sparked a debate concerning whether attentional control, as currently conceptualized and assessed, can be regarded as a valid psychometric construct. In this consensus paper, we summarize the current debate from theoretical, methodological, and analytical perspectives. First, we propose a consensus-based definition of attentional control and the cognitive mechanisms that potentially contribute to individual differences in attentional control. Next, guided by the findings of an in-depth literature survey, we discuss the psychometric considerations that are critical when assessing attentional control. We then provide suggestions for recent methodological and analytical approaches that can alleviate the most common concerns. We conclude that, to truly advance our understanding of the construct of attentional control, we must develop a theory-driven and empirically supported consensus on how we define, operationalize, and assess attentional control. This consensus paper presents a first step to achieve this goal; a shift toward transparent reporting, sharing of materials and data, and cross-laboratory efforts will further accelerate progress. This repository contains the data and R scripts to process, describe and analyze, and plot the literature survey data

What’s Working in Working Memory Training? An Educational Perspective

Working memory training programs have generated great interest, with claims that the training interventions can have profound beneficial effects on children’s academic and intellectual attainment. We describe the criteria by which to evaluate evidence for or against the benefit of working memory training. Despite the promising results of initial research studies, the current review of all of the available evidence of working memory training efficacy is less optimistic. Our conclusion is that working memory training produces limited benefits in terms of specific gains on short-term and working memory tasks that are very similar to the training programs, but no advantage for academic and achievement-based reading and arithmetic outcomes

A review of valve surgery for rheumatic heart disease in Australia

Background: Globally, rheumatic heart disease (RHD) remains an important cause of heart disease. In Australia it particularly affects older non-Indigenous Australians and Aboriginal Australians and/or Torres Strait Islander peoples. Factors associated with the choice of treatment for advanced RHD remain variable and poorly understood. Methods: The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed. Demographics, co-morbidities, pre-operative status and valve(s) affected were collated and associations with management assessed. Results: Surgical management of 1384 RHD and 15843 non-RHD valve procedures was analysed. RHD patients were younger, more likely to be female and Indigenous Australian, to have atrial fibrillation (AF) and previous percutaneous balloon valvuloplasty (PBV). Surgery was performed on one valve in 64.5%, two valves in 30.0% and three valves in 5.5%. Factors associated with receipt of mechanical valves in RHD were AF (OR 2.69) and previous PBV (OR 1.98) and valve surgery (OR 3.12). Predictors of valve repair included being Indigenous (OR 3.84) and having fewer valves requiring surgery (OR 0.10). Overall there was a significant increase in the use of mitral bioprosthetic valves over time. Conclusions: RHD valve surgery is more common in young, female and Indigenous patients. The use of bioprosthetic valves in RHD is increasing. Given many patients are female and younger, the choice of valve surgery and need for anticoagulation has implications for future management of RHD and related morbidity, pregnancy and lifestyle plans