Automaticity and executive abilities in developmental dyslexia: A theoretical review

Cognitive difficulties are well documented in developmental dyslexia but they present a challenge to dyslexia theory. In this paper, the Model of the Control of Action is proposed as a theoretical explanation of how and why deficits in both automaticity and executive abilities are apparent in the cognitive profiles of dyslexia and how these deficits might relate to literacy difficulties. This theoretical perspective is used to consider evidence from different cognitive domains. The neuroanatomical underpinnings of automaticity and executive abilities are then discussed in relation to the understanding of dyslexia. Links between reading, writing, and executive function are considered. The reviewed evidence suggests that dyslexia theory should consider an interaction between procedural learned behaviour (automaticity) and higher-order (executive) abilities. The capacity to handle environmental interference, develop and engage adaptive strategies accordingly, and plan actions all require interactions between the cerebellum and the prefrontal cortex (PFC). Difficulties in these areas might explain both impairments in the cumulative development of literacy skills in childhood and general task management in everyday life in adulthood. It is suggested that improved measures are required to assess this cerebellar–PFC interaction and to allow early identification of future literacy difficulties, allowing implementation of timely interventions and reasonable adjustments

Label-checking strategies to adapt behaviour to design

Despite robust quality control procedures, labelling errors on fresh produce are estimated to cost the UK supermarket industry approximately £50million pounds per year in product recalls and wastage. Changing the format of the labels themselves is not a viable option. Instead, the challenge is to change or guide human operatives' behaviour so that label printing errors do not go undetected during quality control procedures. To this end, a simulated label checking task was presented to naïve participants to compare more systematic and strategic methods of label checking. Two conditions in which behaviour was computer-led were compared with a control condition in which checkers adopted their own idiosyncratic checking method. The data indicate that the two computer-led approaches resulted in improved levels of accuracy. Pushing label checkers towards a more systematic approach would appear to be effective in reducing undetected label errors, and could lead potentially to significant financial savings and reduced environmental wastage in the fresh produce industry

Cognitive predictors of accuracy in quality control checking

Labelling errors on fresh produce are estimated to cost the UK supermarket industry £50m per year in product recalls and wastage. Such errors occur despite robust quality control procedures. Given the financial and environmental impact of these errors, it is important to understand whether labelchecking performance can be predicted by individual differences in cognitive abilities. To this end, participants carried out a simulated label-checking task together with a number of measures of information processing speed, attention, short-term/working memory, and mind-wandering. Accuracy of label checking was found to be significantly predicted by three of the measures, with better short-term verbal memory being most strongly associated with performance. Cognitive tests such as these provide a means of identifying how well employees are likely to perform when undertaking such tasks and, if necessary, how they should be supported in that role, possibly forming a screening battery when recruiting new quality control staff. The findings highlight the importance of determining the component processes of cognition which contribute to performance in real-world work environment

Optimal approaches to the quality control checking of product labels

Quality control checkers at fresh produce packaging facilities occasionally fail to detect incorrect information presented on labels. Despite being infrequent, such errors have significant financial and environmental repercussions. To understand why label-checking errors occur, observations and interviews were undertaken at a large packaging facility and followed up with a laboratory-based label-checking task. The observations highlighted the dynamic, complex environment in which label-checking took place, whilst the interviews revealed that operatives had not received formal training in label-checking. On the laboratory-based task, overall error detection accuracy was high but considerable individual differences were found between professional label-checkers. Response times were shorter when participants failed to detect label errors, suggesting incomplete checking or ineffective checking strategies. Furthermore, eye movement recordings indicated that checkers who adopted a systematic approach to checking were more successful in detecting errors. The extent to which a label checker adopted a systematic approach was not found to correlate with the number of years of experience that they had accrued in label-checking. To minimize the chances of label errors going undetected, explicit instruction and training, personnel selection and/or the use of software to guide performance towards a more systematic approach is recommended

Executive functions in adults with developmental dyslexia

Background: Executive functioning (EF) deficits are well recognized in developmental dyslexia, yet the majority of studies have concerned children rather than adults, ignored the subjective experience of the individual with dyslexia (with regard to their own EFs), and have not followed current theoretical perspectives on EFs. Aims and Methods: The current study addressed these shortfalls by administering a self-report measure of EF (BRIEF-A; Roth, Isquith & Gioia, 2005) and experimental tasks to IQ-matched groups of adults with and without dyslexia. The laboratory-based tasks tested the three factors constituting the framework of EF proposed by Miyake et al. (2000). Results: In comparison to the group without dyslexia, the participants with dyslexia self-reported more frequent EF problems in day-to-day life, with these difficulties centering on metacognitive processes (working memory, planning, task monitoring, and organization) rather than on the regulation of emotion and behaviour. The participants with dyslexia showed significant deficits in EF (inhibition, set shifting, and working memory). Conclusions and Implications: The findings indicated that dyslexia-related problems have an impact on the daily experience of adults with the condition. Further, EF difficulties are present in adulthood across a range of laboratory-based measures, and, given the nature of the experimental tasks presented, extend beyond difficulties related solely to phonological processing

History of Reading Struggles Linked to Enhanced Learning in Low Spatial Frequency Scenes

People with dyslexia, who face lifelong struggles with reading, exhibit numerous associated low-level sensory deficits including deficits in focal attention. Countering this, studies have shown that struggling readers outperform typical readers in some visual tasks that integrate distributed information across an expanse. Though such abilities would be expected to facilitate scene memory, prior investigations using the contextual cueing paradigm failed to find corresponding advantages in dyslexia. We suggest that these studies were confounded by task-dependent effects exaggerating known focal attention deficits in dyslexia, and that, if natural scenes were used as the context, advantages would emerge. Here, we investigate this hypothesis by comparing college students with histories of severe lifelong reading difficulties (SR) and typical readers (TR) in contexts that vary attention load. We find no differences in contextual-cueing when spatial contexts are letter-like objects, or when contexts are natural scenes. However, the SR group significantly outperforms the TR group when contexts are low-pass filtered natural scenes [F(3, 39) = 3.15, p<.05]. These findings suggest that perception or memory for low spatial frequency components in scenes is enhanced in dyslexia. These findings are important because they suggest strengths for spatial learning in a population otherwise impaired, carrying implications for the education and support of students who face challenges in school

Do Baseline Executive Functions Mediate Prospective Memory Performance under a Moderate Dose of Alcohol?

Prospective memory (PM) is memory for delayed intentions. While deleterious effects of acute doses of alcohol on PM have been documented previously using between-subjects comparisons, the current study adopted a single blind placebo-controlled within-subjects design to explore whether the extent to which alcohol-related impairments in PM are mediated by executive functions (EFs). To this end, 52 male social drinkers with no history of substance-related treatment were tested using two parallel versions of a clinical measure of PM (the Memory for Intentions Test; Raskin, Buckheit & Sherrod, 2010), and a battery of EF measures. Testing took place on two occasions, with the order of administration of the alcohol and placebo conditions being fully counterbalanced. Overall, PM was worse under alcohol and participants showed deficits on five of the six subscales making up the clinical test. Hierarchical multiple regression analyses demonstrated that EFs did not predict PM performance decrements overall but did predict performance when time cues were presented and when verbal responses were required. Phonemic fluency was the strongest of the EF predictors; a greater capacity to gain controlled access to information in long-term memory predicted a smaller difference between placebo- and alcohol-related performance on both the time cue and verbal response scales. Prospective memory is crucial to compliance with, and response to, both therapy programmes and alcohol harm prevention campaigns. The results indicate that individual differences in cognitive function need to be taken into account when designing such interventions in order to increase their effectiveness