Miyake, Friedman, Emerson, Witzki, Howerter and Wager (2000) have argued that the central executive is fractionated consisting of at least three separable component processes: updating, shifting, and inhibition. The Wisconsin Card Sort Test, random letter generation, Brooks spatial sequences, reading and computation span, word fluency, and a measure of dual task performance were administered to 95 individuals aged between 20 and 81, average age 41.89. The executive measures were factor analyzed, using the oblique rotation method, yielding four factors. The factor structure obtained was broadly consistent with Miyake et al's. However, an additional factor, the only one not to show a significant performance decline with age, was also obtained and was believed to reflect the efficiency of access to long-term memory.

Working memory impairments in dyslexia are well documented. However, research has mostly been limited to the phonological domain, a modality in which dyslexics have a range of problems. In this paper, 22 adult student dyslexics and 22 age-and IQ-matched controls were presented with both verbal and visuospatial working memory tasks. Performance was compared on measures of simple span, complex span (requiring both storage and processing), and dynamic memory updating in the two domains. The dyslexic group had significantly lower spans than the controls on all the verbal tasks, both simple and complex, and also on the spatial complex span measure. Impairments remained on the complex span measures after controlling statistically for simple span performance, suggesting a central executive impairment in dyslexia. The novelty of task demands on the initial trials of the spatial updating task also proved more problematic for the dyslexic than control participants. The results are interpreted in terms of extant theories of dyslexia. The possibility of a Supervisory Attentional System deficit in dyslexia is also raised. It seems clear that working memory difficulties in dyslexia extend into adulthood, can affect performance in both the phonological and visuospatial modalities, and implicate central executive dysfunction, in addition to problems with storage.Working memory and dyslexia 3 Author NoteWe are grateful to Dr Viv Moore, Dr David Glasspool, and Andy Velarde for their support in producing this paper and would also like to thank Prof. Martin Conway, Prof.Susan Gathercole, and two anonymous reviewers for their helpful comments on earlier versions of this manuscript.Correspondence concerning this article should be addressed to Jamie Smith-Spark, Department of Psychology, London South Bank University, 103 Borough Road, London, SE1 0AA, UK.Working memory and dyslexia 4 Central Executive Functioning in Developmental DyslexiaDyslexia is the most prevalent developmental disorder, affecting some 5% of the population of the western world (Badian, 1984), despite adequate intelligence, education, and socioeconomic status. It is most commonly defined as a problem with the decoding of the written word, with such processing difficulties leading to the formulation of the phonological core deficit hypothesis of dyslexia (e.g., Frith, 1985;Ramus, 2003;Ramus, Pidgeon, & Frith, 2003; Snowling, 2000; Snowling & Griffiths, 2003; Stanovich, 1988; Vellutino, 1979; Vellutino, Fletcher, Snowling, & Scanlon, 2004). However, impairments in a number of other domains have been reported in both the laboratory and in everyday life. These wide ranging problems have led to the formulation of rival explanations of dyslexia that, whilst consistent with phonological deficits, view the condition from a broader theoretical perspective (e.g., Goswami, 2002; Nicolson & Fawcett, 1990; Nicolson, Fawcett, & Dean, 1995, 2001 Stein & Walsh, 1997; Tallal, Miller, & Fitch, 1993; Wolf & Bowers, 1999; for a review of these theories and the genetic basi...

Current and previous users of the drug MDMA ('ecstasy') were tested on measures of central executive functioning, information processing speed, and on self-report measures of arousal and anxiety. The results were compared with those for a control group who did not use MDMA. Relative to the control group, both user groups were found to be impaired in some aspects of central executive functioning. Also, there were significant group differences on the measures of anxiety (users were more anxious) and on arousal (previous users scoring higher on the arousal measure relative to current users). Users processed information as quickly as non-users but less accurately. Some possible mediators of the above group differences are discussed.

Numerous studies have shown paranormal believers misperceive randomness and are poor at judging probability. Despite the obvious relevance to many types of alleged paranormal phenomena, no one has examined whether believers are more susceptible to the 'conjunction fallacy'; that is to misperceiving co-occurring (conjunct) events as being more likely than singular (constituent) events alone. The present study examines believer vs. non-believer differences in conjunction errors for both paranormal and non-paranormal events presented as either a probability or a frequency estimation task. As expected, believers made more conjunction errors than non-believers. This was true for both event types, with both groups making fewer errors for paranormal than for non-paranormal events. Surprisingly, the response format (probability vs. frequency) had little impact. Results are discussed in relation to paranormal believers' susceptibility to the conjunction fallacy and more generally, to their propensity for probabilistic reasoning biases.

This article will provide an overview of the psychosocial and cognitive problems that people with epilepsy (PWE) experience as consequence of the condition and its treatment. Psychosocial problems will be discussed in light of how they impact on quality of life. The review will discuss the stigma, myths and stereotypes that PWE encounter and the implications of these for important psychological outcomes including; anxiety, depression, self-esteem, sense of mastery and cognitive dysfunction. The latter part of the article will focus on psychosocial factors including social isolation, interpersonal and family relationships and employment. The overall aim is to provide the reader with a general overview of the sort of factors that can impede social functioning in PWE with particular emphasis on the problems encountered in adults.

In a study (N = 61) comparing older (age range = 60-80 years, M = 67) and younger (age range = 20-33 years, M = 25) people, age deficits were observed in working memory, perceptual speed, and central executive functioning but not in phonological loop functioning. Controlling for age differences in central executive performance removed over 50% of the age-related variance in working memory span. However, controlling for perceptual speed removed all of the age-related variance in working memory span. In addition, age differences in central executive functioning were largely eliminated after controlling for age deficits in perceptual speed. These findings suggest that age differences in central executive functioning are primarily attributable to a general slowdown in the rate at which information is activated within the working memory system and that no specific deficits in the central executive occur as a consequence of aging. 316This document

Rationale/Objectives: Recent theoretical models suggest that the central executive may not be a unified structure. The present study explored the nature of central executive deficits in ecstasy users. Methods: In Study One, 27 ecstasy users and 34 nonusers were assessed using tasks to tap memory updating (computation span; letter updating) and access to long-term memory (a semantic fluency test and the Chicago word fluency test). In Study Two, 51 ecstasy users and 42 nonusers completed tasks that assess mental set switching (number/letter and plus/minus) and inhibition (random letter generation). Results: MANOVA revealed that ecstasy users performed worse on both tasks used to assess memory updating, and on tasks to assess access to long-term memory (C-and S-letter fluency). However, notwithstanding the significant ecstasy-group related effects, indices of cocaine and cannabis use were also significantly correlated with most of the executive measures. Unexpectedly, in Study Two, ecstasy users performed significantly better on the inhibition task producing more letters than nonusers. No group differences were observed on the switching tasks. Correlations between indices of ecstasy use and number of letters produced were significant. Conclusions: The present study provides further support for ecstasy/polydrug related deficits in memory updating and in access to long-term memory. The surplus evident on the inhibition task should be treated with some caution as this was limited to a single measure and has not been supported by our previous work.

There is long-standing evidence for verbal working memory impairments in both children and adults with dyslexia. By contrast, spatial memory appears largely to be unimpaired. In an attempt to distinguish between phonological and central executive accounts of the impairments in working memory, a set of phonological and spatial working memory tasks was designed to investigate the key issues in working memory, task type, task demands (static, dynamic, and updating), and task complexity. Significant differences emerged between the dyslexic and non-dyslexic participants on the verbal working memory tasks employed in Experiment 1, thereby providing further evidence for continuing dyslexic impairments of working memory into adulthood. The nature of the deficits suggested a problem with the phonological loop, with there being little evidence to implicate an impairment of the central executive. Due to the difficulties associated with separating verbal working memory and phonological processing, however, performance was investigated in Experiment 2 using visuo-spatial measures of working memory. The results of the visuo-spatial tasks indicated no between-group differences in static spatial memory, requiring the short-term storage of simultaneously presented information. In almost all conditions there were no between-group differences in dynamic spatial memory that demands the recall of both location and order of stimuli presented sequentially. However, a significant impairment occurred on the dynamic task under high memory updating load, on which dyslexic adults showed non-phonological working memory deficits. In the absence of an explanation in terms of verbal recoding, this finding is interpreted in terms of a central executive or automaticity impairment in dyslexia. ACKNOWLEDGEMENTS.