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Processing Speed (processing + speed)
Selected AbstractsRelations between measures of Cattell-Horn-Carroll (CHC) cognitive abilities and mathematics achievement across the school-age yearsPSYCHOLOGY IN THE SCHOOLS, Issue 2 2003RANDY G. FLOYD Cognitive clusters from the Woodcock-Johnson III (WJ III) Tests of Cognitive Abilities that measure select Cattell-Horn-Carroll broad and narrow cognitive abilities were shown to be significantly related to mathematics achievement in a large, nationally representative sample of children and adolescents. Multiple regression analyses were used to predict performance on the Math Calculation Skills and Math Reasoning clusters from the WJ III Tests of Achievement for 14 age groups ranging in age from 6 to 19 years. Comprehension-Knowledge (Gc) demonstrated moderate relations with Math Calculation Skills after the early school-age years and moderate to strong relations with Math Reasoning. Fluid Reasoning (Gf), Short-term Memory (Gsm), and Working Memory generally demonstrated moderate relations with the mathematics clusters. Processing Speed (Gs) demonstrated moderate relations with Math Reasoning during the elementary school years and moderate to strong relations with Math Calculation Skills. During the earliest ages of the analysis, Long-term Retrieval (Glr) demonstrated moderate relations with the mathematics clusters, and Auditory Processing (Ga) demonstrated moderate relations with Math Calculation Skills. Visual-Spatial Thinking (Gv) generally demonstrated nonsignificant relations with the mathematics clusters. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 155,171, 2003. [source] Cognitive effects of hormonal therapy in early stage breast cancer patients: a prospective studyPSYCHO-ONCOLOGY, Issue 8 2009Barbara Collins Abstract Objective: The primary purpose of this study was to evaluate the cognitive effects of adjuvant hormonal therapies in breast cancer patients. Participants and Methods: Post-menopausal breast cancer patients scheduled to receive tamoxifen (n=31) or anastrozole (n=14) completed neuropsychological testing around the time of commencement of treatment (T1), and again 5,6 months later (T2). A sample of healthy female volunteers (n=28) was tested at comparable intervals. A standardized regression-based approach was used to assess cognitive change. This method uses test/retest scores of the healthy control group to generate an equation that predicts T2 scores from T1 scores. The difference between the predicted and obtained T2 scores divided by the standard error of the estimate produces a deviation score that reflects the discrepancy from the T1,T2 difference scores that would be expected on the basis of practice and error alone. Results: Analysis of individual deviation scores revealed that both the patients taking tamoxifen and those taking anastrozole were more likely than healthy controls to show reliable cognitive decline from T1 to T2 (39, 64, and 7%, respectively). Processing speed and verbal memory were the cognitive domains most affected. Conclusion: These data suggest that hormonal therapies exert a subtle negative influence on cognition in breast cancer patients. Further analyses indicated that this effect was not fully accounted for by demographic factors or fatigue. Methodological limitations of the current study are addressed, along with recommendations for future studies in this area. Copyright © 2008 John Wiley & Sons, Ltd. [source] Is late-onset schizophrenia a subtype of schizophrenia?ACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2010I. V. Vahia Vahia IV, Palmer BW, Depp C, Fellows I, Golshan S, Kraemer HC, Jeste DV. Is late-onset schizophrenia a subtype of schizophrenia? Objective:, To determine whether late-onset schizophrenia (LOS, onset after age 40) should be considered a distinct subtype of schizophrenia. Method:, Participants included 359 normal comparison subjects (NCs) and 854 schizophrenia out-patients age >40 (110 LOS, 744 early-onset schizophrenia or EOS). Assessments included standardized measures of psychopathology, neurocognition, and functioning. Results:, Early-onset schizophrenia and LOS groups differed from NCs on all measures of psychopathology and functioning, and most cognitive tests. Early-onset schizophrenia and LOS groups had similar education, severity of depressive, negative, and deficit symptoms, crystallized knowledge, and auditory working memory, but LOS patients included more women and married individuals, had less severe positive symptoms and general psychopathology, and better processing speed, abstraction, verbal memory, and everyday functioning, and were on lower antipsychotic doses. Most EOS,LOS differences remained significant after adjusting for age, gender, severity of negative or deficit symptoms, and duration of illness. Conclusion:, Late-onset schizophrenia should be considered a subtype of schizophrenia. [source] Phenotypic variation and FMRP levels in fragile XDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2004Danuta Z. Loesch Abstract Data on the relationships between cognitive and physical phenotypes, and a deficit of fragile X mental retardation 1 (FMR1) gene-specific protein product, FMRP, are presented and discussed in context with earlier findings. The previously unpublished results obtained, using standard procedures of regression and correlations, showed highly significant associations in males between FMRP levels and the Wechsler summary and subtest scores and in females between these levels and the full-scale intelligence quotient (FSIQ), verbal and performance IQ, and some Wechsler subtest scores. The published results based on data from 144 extended families with fragile X, recruited from Australia and the United States within a collaborative NIH-supported project, were obtained using robust modification of maximum likelihood in pedigrees. The results indicated that processing speed, short-term memory, and the ability to control attention, especially in the context of regulating goal-directed behavior, may be primarily affected by the FMRP depletion. The effect of this depletion on physical phenotype was also demonstrated, especially on body and head height and extensibility of finger joints. It is recommended that further studies should rely on more accurate measures of FMRP levels, and use of larger samples, to overcome extensive variability in the data. MRDD Research Reviews 2004;10:31,41. © 2004 Wiley-Liss, Inc. [source] Working memory, processing speed, and set-shifting in children with developmental coordination disorder and attention-deficit,hyperactivity disorderDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 9 2007Jan P Piek BSc (Hons) PhD It has been suggested that the high levels of comorbidity between attention-deficit-hyperactivity disorder (ADHD) and developmental coordination disorder (DCD) may be attributed to a common underlying neurocognitive mechanism. This study assessed whether children with DCD and ADHD share deficits on tasks measuring working memory, set-shifting, and processing speed. A total of 195 children aged between 6 years 6 months and 14 years 1 month (mean 10y 4mo [SD 2y 2mo]) were included in this study. A control group (59 males, 79 females), a DCD group (12 males, six females), an ADHD-predominantly inattentive group (16 males, four females), and an ADHD-combined group (15 males, four females), were tested on three executive functioning tasks. Children with DCD were significantly slower on all tasks, supporting past evidence of a timing deficit in these children. With few exceptions, children with ADHD did not perform more poorly than control children. These findings demonstrate the importance of identifying children with motor deficits when examining tasks involving a timing component. [source] Neuropsychological effects of hyperbaric oxygen therapy in cerebral palsyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2002Paule Hardy We conducted a double-blind placebo study to investigate the claim that hyperbaric oxygen treatment (HBO2) improves the cognitive status of children with cerebral palsy (CP). Of 111 children diagnosed with CP (aged 4 to 12 years), only 75 were suitable for neuropsychological testing, assessing attention, working memory, processing speed, and psychosocial functioning. The children received 40 sessions of HBO2 or sham treatment over a 2-month period. Children in the active treatment group were exposed for 1 hour to 100% oxygen at 1.75 atmospheres absolute (ATA), whereas those in the sham group received only air at 1.3 ATA. Children in both groups showed better self-control and significant improvements in auditory attention and visual working memory compared with the baseline. However, no statistical difference was found between the two treatments. Furthermore, the sham group improved significantly on eight dimensions of the Conners'Parent Rating Scale, whereas the active treatment group improved only on one dimension. Most of these positive changes persisted for 3 months. No improvements were observed in either group for verbal span, visual attention, or processing speed. [source] Balancing and pointing tasks in dyslexic and control adultsDYSLEXIA, Issue 4 2006Catherine J. Stoodley Abstract Developmental dyslexia may affect as much as 15% of the population, but the aetiology of the disorder is still being debated. The cerebellar theory of dyslexia proposes that cerebellar dysfunction could lead to the myriad of symptoms seen in dyslexic individuals, both in literacy and non-literacy domains. The cerebellum is crucial to the fluent performance of motor skills. Previous studies have found that dyslexic children are worse than control children on certain motor and balancing tasks. Here the performance of 28 dyslexic compared to 26 control adults on rapid pointing and balancing measures, tasks which are thought to reflect cerebellar function, was investigated. There were no significant differences between the dyslexic and control participants on the balancing tasks or when the speed and accuracy of pointing were analysed separately. However, when the speed and accuracy of pointing were combined, the dyslexic participants showed poorer performance than the controls (p = 0.045). Furthermore, there were significant relationships between performance on the pointing task and literacy skills, and regression analysis showed that the error and speed of pointing contributed significantly to the variance in literacy skill. The implications for the role of the cerebellum and processing speed in dyslexia are discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] Cognitive functioning in substance abuse and dependence: a population-based study of young adultsADDICTION, Issue 9 2009Antti Latvala ABSTRACT Aims To investigate whether substance use disorders (SUDs) are associated with verbal intellectual ability, psychomotor processing speed, verbal and visual working memory, executive function and verbal learning in young adults, and to study the associations of SUD characteristics with cognitive performance. Participants A population-based sample (n = 466) of young Finnish adults aged 21,35 years. Measurements Diagnostic assessment was based on all available information from a structured psychiatric interview (SCID-I) and in- and out-patient medical records. Established neuropsychological tests were used in the cognitive assessment. Confounding factors included in the analyses were comorbid psychiatric disorders and risk factors for SUDs, representing behavioural and affective factors, parental factors, early initiation of substance use and education-related factors. Findings Adjusted for age and gender, life-time DSM-IV SUD was associated with poorer verbal intellectual ability, as measured with the Wechsler Adult Intelligence Scale,Revised (WAIS-R) vocabulary subtest, and slower psychomotor processing, as measured with the WAIS-R digit symbol subtest. Poorer verbal intellectual ability was accounted for by parental and own low basic education, whereas the association with slower psychomotor processing remained after adjustment for SUD risk factors. Poorer verbal intellectual ability was related to substance abuse rather than dependence. Other SUD characteristics were not associated with cognition. Conclusions Poorer verbal intellectual ability and less efficient psychomotor processing are associated with life-time alcohol and other substance use disorders in young adulthood. Poorer verbal intellectual ability seems to be related to parental and own low basic education, whereas slower psychomotor processing is associated with SUD independently of risk factors. [source] The Effects of Adjunctive Topiramate on Cognitive Function in Patients with EpilepsyEPILEPSIA, Issue 3 2003Suzee Lee Summary: ,Purpose: We investigated possible cognitive effects of topiramate (TPM) in polypharmacy on patients with intractable epilepsy. Methods: Study 1 evaluated 22 consecutively admitted patients whose antiepileptic drugs (AEDs) on admission to the Montreal Neurological Hospital included TPM. Performance on neuropsychological tests administered on and subsequently off TPM was analyzed. Four patients also were tested before taking TPM, allowing comparisons off, then on, and then off the drug again. Measures included intellectual function, verbal and nonverbal memory, language, word and design fluency, somatosensory sensitivity, and motor skills. In Study 2, 16 patients at the Minnesota Epilepsy Group were tested first off, then on TPM with nine cognitive tasks that measured concentration, verbal fluency, language, and psychomotor speed. Results: In Study 1, significant (p , 0.01) improvements were observed off TPM on 13 measures including verbal and nonverbal fluency and certain verbal and perceptual tasks. Notably, verbal learning and memory were unaffected; a limited effect was observed on nonverbal memory. Patients tested 3 times scored better in both tests off TPM compared with on this drug. In Study 2, declines on TPM were observed on all measures, significantly (p , 0.05) for tests of fluency, sustained concentration, and visual motor processing speed. Conclusions: TPM was associated with declines in fluency, attention/concentration, processing speed, language skills, and perception; working memory but not retention was affected. As the two studies used an opposite order of testing on versus off TPM, our results clearly show a performance decrement while patients are taking TPM, without respect to which condition is tested first. [source] Fatigue and processing speed are related in multiple sclerosisEUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2010A. K. Andreasen Background:, Fatigue is common in multiple sclerosis (MS) and could be related to impaired processing speed caused by MS specific brain alterations. The objective of this study was to examine the relationship between processing speed and fatigue in patients with relapsing remitting MS. Methods:, Patients with EDSS score ,3.5 were grouped as fatigued [Fatigue Severity Scale (FSS) score ,5.0] or non-fatigued (FSS score ,4.0). Patients with FSS scores ,5 were categorized as primary or secondary fatigued according to various indices. A cognitive test battery obtained from Wechsler's Adult Intelligence Scale-III/Wechsler's Memory Scale-III was applied. Results:, Processing speed (Digit Symbol Coding) was lower amongst all MS patients being 9.4(2.9) in primary fatigued, 8.3(2.8) in secondary fatigued and 10.3(2.7) in non-fatigued versus 12.3(3.0) in healthy controls. In the combined group of primary and secondary fatigued MS patients, processing speed was slower than that in non-fatigued MS patients and inversely related to fatigue (r = ,0.35; P < 0.05). No such relationship could be established in non-fatigued MS patients or in healthy controls. Conclusion:, The degree of fatigue in MS is related to processing speed impairment and longitudinal studies should clarify their mutual dependency. [source] Speed of Processing and Face Recognition at 7 and 12 MonthsINFANCY, Issue 4 2002Susan A. Rose This research examined developmental and individual differences in infants' speed of processing faces and the relation of processing speed to the type of information encoded. To gauge processing speed, 7- and 12-month-olds were repeatedly presented with the same face (frontal view), each time paired with a new one, until they showed a consistent preference for the new one. Subsequent probe trials assessed recognition of targets that either preserved configural integrity (Study 1: 3/4 profile and full profile poses) or disrupted it while preserving featural information (Study 2: rotations of 160° or 200° and fracturings). There were developmental differences in both speed and in infants' appreciation of information about faces. Older infants took about 60% fewer trials to reach criterion and had more mature patterns of attention (i.e., looks of shorter duration and more shifts of gaze). Whereas infants of both ages recognized the familiar face in a 3/4 pose, the 12-month-olds also recognized it in profile and when rotated. Twelve-month-olds who were fast processors additionally recognized the fractured faces; otherwise, processing speed was unrelated to the type of information extracted. At 7 months then, infants made use of some configural information in processing faces; at 12 months, they made use of even more of the configural information, along with part-based or featural information. [source] A binary-based on-chip CNN solution for pixel-level snakesINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 4 2006V. M. Brea Abstract This paper introduces a binary-based on-chip cellular neural network (CNN) solution for pixel-level snakes. Every cell in the array comprises circuitry for B/W and grey-scale processing. The B/W processing is performed with a positive range high-gain discrete-time (DT)CNN model with 1-bit of programmability. The grey-scale processing is executed on a dedicated sub-cell. The design efforts are mainly focused on area consumption and processing speed. The result is a chip with a resolution of 9 × 9 cells in a 0.18 µm CMOS technology process and a density of more than 700cells/mm2. Simulations at schematic level lead to a time of less than 100ns for every DTCNN step. The peak power dissipation is kept at a few watts in a hypothetical chip of 128 × 128 cells. Copyright © 2006 John Wiley & Sons, Ltd. [source] Cellular neural networks based on resonant tunnelling diodesINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 5 2001Martin Hänggi Resonant tunnelling diodes (RTDs) have intriguing properties which make them a primary nanoelectronic device for both analogue and digital applications. We propose two different types of RTD-based cells for the cellular neural network (CNN) which exhibit superior performance in terms of complexity, functionality, or processing speed compared to standard cells. In the first cell model, the resistor of the standard cell is replaced by an RTD, which results in a more compact and versatile cell which requires neither self-feedback nor a non-linear output function, and allows three stable equilibrium points. If a resonant tunnelling transistor (RTT) is used instead of the RTD, the dynamics can be controlled through its gate voltage as an additional network parameter. In a majority of CNN applications, bistable cells are sufficient. Utilizing RTD-based bistable logic elements to store the state of the cell, switching occurs almost instantaneously as virtually no charge transfer is necessary, and it is possible to implement non-linear connections in a straightforward manner. Hence, it turns out that RTD-based CNNs are tailor-made for the implementation of extremely fast bipolar operations and non-linear templates. The ideas presented in this paper may also be beneficially applied to other types of circuits and systems such as A/D converters or sigma-delta modulators. Copyright © 2001 John Wiley & Sons, Ltd. [source] The effect of chronic benzodiazepine use on cognitive functioning in older persons: good, bad or indifferent?INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2007E. J. M. Bierman Abstract Objective This study investigates the effects of benzodiazepine (BZ) use on cognitive performance in elderly persons in a longitudinal design. Study design and setting Data were obtained from the Longitudinal Aging Study Amsterdam (LASA), in the Netherlands. 2,105 respondents (,62 years of age) were included and had repeated measurements over a period of 9 years. For all BZs the type, dosage, frequency and duration of use was measured. The equivalent of a dose of diazepam was determined with regard to type and dosage and a cumulative dosage was calculated. General cognitive functioning was measured with the Mini-Mental State Examination, information processing speed was measured with the coding task, fluid intelligence with Raven's Coloured Progressive Matrices and episodic memory with the Auditory Verbal Learning Test. Multilevel analyses were used to investigate the relationship between BZ use and cognitive decline. Results A negative effect of BZ use on cognitive performance was found. However, the effect sizes were very small. Conclusion This study suggests that both duration and cumulative exposure to BZ has a small negative effect on the long-term cognitive functioning of elderly people in the community. Copyright © 2007 John Wiley & Sons, Ltd. [source] Apathy and cognitive performance in older adults with depressionINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 6 2003Denise Feil Abstract Objectives Recent studies have linked apathy to frontal lobe dysfunction in persons with dementia, but few studies have explored this relationship in older, depressed persons without dementia. We examined the association between apathy and cognitive function in a group of older persons with major depression using standardized neuropsychological tests. We hypothesized that presence of apathy in depression is associated with poorer frontal executive performance. Methods We analyzed data from 89 older adults with major depression. We defined apathy using four items from the Hamilton Psychiatric Rating Scale for Depression which reflect the clinical state of apathy, including ,diminished work/interest,' ,psychomotor retardation,' ,anergy' and ,lack of insight.' Results Apathy most strongly correlated with two verbal executive measures (Stroop C and FAS), a nonverbal executive measure (Wisconsin Card Sorting Test,Other Responses), and a measure of information processing speed (Stroop B). Apathy was not associated with age, sex, education, medical illness burden, Mini-Mental State Examination score and Full Scale IQ score. Stepwise regression analyses of significant cognitive tests showed that apathy alone or apathy plus depression severity, age, or education accounted for a significant amount of the variance. Conclusions The results of this study provide support for an apathy syndrome associated with poorer executive function in older adults with major depression. Copyright © 2003 John Wiley & Sons, Ltd. [source] Depth of anaesthesia and post-operative cognitive dysfunctionACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010J. STEINMETZ Background: A deep level of anaesthesia measured by the bispectral index has been found to improve processing speed as one aspect of cognitive function after surgery. The purpose of the present study was to assess the possible effect of the level of anaesthesia on post-operative cognitive dysfunction (POCD) 1 week after surgery, as assessed by a neuropsychological test battery. Methods: We included 70 patients >60 years of age scheduled for elective non-cardiac surgery with general anaesthesia. The depth of anaesthesia was monitored using the cerebral state monitor, which provided a cerebral state index (CSI) value. Cognitive function was assessed by the ISPOCD neuropsychological test battery before and at 1 week (or hospital discharge) after surgery and POCD was defined as a Z score above 1.96. Results: Five patients were not assessed after surgery. The mean CSI was 40 and 43 in patients with (N=9) and without POCD (N=56), respectively (P=0.41). The cumulated time of both deep anaesthesia (CSI<40) and light anaesthesia (CSI>60) did not differ significantly, and no significant correlation was found between the mean CSI and the Z score. Conclusion: We were unable to detect a significant association between the depth of anaesthesia and the presence of POCD 1 week after the surgery. [source] Depressive Symptoms and Cognitive Decline in Community-Dwelling Older AdultsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 5 2010Sebastian Köhler PhD OBJECTIVES: To examine the temporal association between depressive symptoms and cognitive functioning and estimate the effect measure modification of the apolipoprotein E (APOE) ,4 allele on this relationship. DESIGN: Prospective cohort study. SETTING: General community. PARTICIPANTS: Population-based sample of 598 cognitively intact older adults aged 60 and older, with re-assessments after 3 (N=479) and 6 years (N=412). MEASUREMENTS: Depressive symptoms (Symptom Checklist) and neurocognitive functioning (memory, Visual Verbal Learning Test; attention, Stroop Color,Word Test; processing speed, Letter Digit Substitution Test; general cognition, Mini-Mental State Examination). Longitudinal associations were assessed using linear mixed models. The risk for cognitive impairment, no dementia (CIND) was examined using logistic regression. RESULTS: Adjusting for age, sex, education, and baseline cognition, the rate of change in memory z -scores was 0.00, ,0.11, ,0.20, and ,0.37 for those in the lowest (reference group), second, third, and highest depressive symptom quartiles at baseline, respectively (P<.001 for highest vs lowest quartile). The odds ratios for developing CIND with amnestic features were 1.00, 0.87, 0.69, and 2.98 for the four severity groups (P=.05 for highest vs lowest quartile). Associations were strongest for those with persistent depressive symptoms, defined as high depressive symptoms at baseline and at least one follow-up visit. Results were similar for processing speed and global cognitive function but were not as strong for attention. No APOE interaction was observed. CONCLUSION: Depression and APOE act independently to increase the risk for cognitive decline and may provide targets for prevention and early treatment. [source] Adaptive control for edge alignment in polyester film processingADVANCES IN POLYMER TECHNOLOGY, Issue 3 2007Chang-Chiun Huang Abstract Edge alignment of polyester (PET) films is important for achieving product quality and processing speed in winding, coating, drying, and other processes. The edge alignment can be achieved by lateral deflection control, provided that the film tension and transport speed are even at desired values. This article aims to correct the lateral deflection of films by designing robust controllers to swivel the guiding rollers and to maintain even tension and speed at target levels. The self-tuning neuro-proportional integral derivative controller and adaptive high-gain output feedback controller are adopted to guide the lateral deflection so that the film aligns at the desired position. A control scheme, neuron controller by associative learning, is used for maintaining tension and speed control. These strategies are applied to a simplified PET film processing system. The experimental results demonstrate that in our setup, the control schemes can effectively alleviate not only the lateral deflection but also the tension and speed fluctuation at target levels. © 2008 Wiley Periodicals, Inc. Adv Polym Techn 26:153,162, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20096 [source] The Effects of Fetal Alcohol Syndrome on Response Execution and Inhibition: An Event-Related Potential StudyALCOHOLISM, Issue 11 2009Matthew J. Burden Background:, Both executive function deficits and slower processing speed are characteristic of children with fetal alcohol exposure, but the temporal dynamics of neural activity underlying cognitive processing deficits in fetal alcohol spectrum disorder have rarely been studied. To this end, event-related potentials (ERPs) were used to examine the nature of alcohol-related effects on response inhibition by identifying differences in neural activation during task performance. Methods:, We recorded ERPs during a Go/No-go response inhibition task in 2 groups of children in Cape Town, South Africa (M age = 11.7 years; range = 10 to 13),one diagnosed with fetal alcohol syndrome (FAS) or partial FAS (FAS/PFAS; n = 7); the other, a control group whose mothers abstained or drank only minimally during pregnancy (n = 6). Children were instructed to press a "Go" response button to all letter stimuli presented except for the letter "X," the "No-go" stimulus, which occurred relatively infrequently. Results:, Task performance accuracy and reaction time did not differ between groups, but differences emerged for 3 ERP components,P2, N2, and P3. The FAS/PFAS group showed a slower latency to peak P2, suggesting less efficient processing of visual information at a relatively early stage (,200 ms after stimulus onset). Moreover, controls showed a larger P2 amplitude to Go versus No-go, indicating an early discrimination between conditions that was not seen in the FAS/PFAS group. Consistent with previous literature on tasks related to cognitive control, the control group showed a well-defined, larger N2 to No-go versus Go, which was not evident in the FAS/PFAS group. Both groups showed the expected larger P3 amplitude to No-go versus Go, but this condition difference persisted in a late slow wave for the FAS/PFAS group, suggesting increased cognitive effort. Conclusions:, The timing and amplitude differences in the ERP measures suggest that slower, less efficient processing characterizes the FAS/PFAS group during initial stimulus identification. Moreover, the exposed children showed less sharply defined components throughout the stimulus and response evaluation processes involved in successful response inhibition. Although both groups were able to inhibit their responses equally well, the level of neural activation in the children with FAS/PFAS was greater, suggesting more cognitive effort. The specific deficits in response inhibition processing at discrete stages of neural activation may have implications for understanding the nature of alcohol-related deficits in other cognitive domains as well. [source] On the association between serial naming speed for letters and digits and word-reading skill: towards a developmental accountJOURNAL OF RESEARCH IN READING, Issue 4 2005Judith A. Bowey The current study examined several alternative explanations of the association between serial naming speed within fourth-grade children by determining the extent to which the association between word reading and naming speed for letters and numbers is mediated by global processing speed, alphanumeric symbol processing efficiency and phonological processing ability. Children were given multiple measures of key constructs, i.e. word-level reading, serial naming of both alphanumeric and non-alphanumeric items, phonological processing ability, articulation rate and global processing speed. The robust association between alphanumeric naming speed and reading within fourth-grade children was largely mediated by phonological processing ability. Markedly different patterns of results were observed for naming speed for letters and digits and naming speed for colours and pictures in children of this age. Relative to the latter, alphanumeric naming speed better assesses an underlying phonological processing ability that is common to word-reading ability. We argue that item identification processes contribute little to individual differences in alphanumeric naming speed within relatively proficient readers and that the extent to which alphanumeric naming speed primarily reflects phonological processing is likely to vary with the level of overlearning of letters and numbers and their names. [source] Characterizing behavioral and cognitive dysexecutive changes in progressive supranuclear palsyMOVEMENT DISORDERS, Issue 2 2006David Millar DClinPsy Abstract Frontal lobe dysfunction is a prominent feature of many neurological disorders. Early diagnosis may be enhanced by establishing a profile of cognitive, behavioral, and emotional change. Traditional psychometric assessment focuses on cognitive dysfunction and fails to identify behavioral changes, particularly those associated with orbitofrontal dysfunction. We examined progressive supranuclear palsy (PSP), a prototypical subcortical dementia with frontal features, using commonly available neuropsychological measures and a modification of the Katz Adjustment Scale-Relatives (KAS-R), an instrument first developed to assess dysexecutive changes in head-injured patients. Executive tests identified deficits in reasoning, planning, set shifting, verbal fluency, information processing speed, and response initiation. On the KAS-R, changes in apathy, social withdrawal, and independence were observed, with little change in belligerence, social irresponsibility, uncooperativeness, obstreperousness, anxiety, and depression. The results show the potential utility of this instrument in characterizing behavioral and emotional changes associated with frontal lobe dysfunction in neurodegenerative disease. © 2005 Movement Disorder Society [source] Scheduling parallel machines with inclusive processing set restrictionsNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 4 2008Jinwen Ou Abstract We consider the problem of assigning a set of jobs to different parallel machines of the same processing speed, where each job is compatible to only a subset of those machines. The machines can be linearly ordered such that a higher-indexed machine can process all those jobs that a lower-indexed machine can process. The objective is to minimize the makespan of the schedule. This problem is motivated by industrial applications such as cargo handling by cranes with nonidentical weight capacities, computer processor scheduling with memory constraints, and grades of service provision by parallel servers. We develop an efficient algorithm for this problem with a worst-case performance ratio of + ,, where , is a positive constant which may be set arbitrarily close to zero. We also present a polynomial time approximation scheme for this problem, which answers an open question in the literature. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 [source] Locus of the effect of temporal preparation: Evidence from the lateralized readiness potentialPSYCHOPHYSIOLOGY, Issue 4 2003Hiltraut MÜller-Gethmann Abstract It is well established that reaction time (RT) is shorter when a response signal is preceded by a warning signal, because the warning signal causes the participant to prepare for the upcoming response. A review of chronometric and psychophysiological studies reveals the prevailing view that this temporal preparation operates mainly at a motor level speeding up rather late processes. To assess the locus of this preparation effect, we conducted two experiments employing the lateralized readiness potential (LRP). Contrary to this prevailing view, the results of both experiments clearly indicate that temporal preparation enhances the processing speed of relatively early processes, because a manipulation of temporal uncertainty affected RT, the P300 latency, and the stimulus-to-LRP interval but not the LRP-to-keypress interval. [source] Do fall predictors in middle aged and older adults predict fall status in persons 50+ with fibromyalgia?RESEARCH IN NURSING & HEALTH, Issue 3 2010An exploratory study Abstract We explored potential predictors of fall status in 70 community-dwelling persons ,50 years of age with fibromyalgia (FM). Over 40% of the sample reported one or more falls in the year prior to the study. A logistic regression model using 10 variables known to predict falls in middle aged and older persons predicted 45% of the variance in fall status. Three variables offered significant independent contributions to the overall model predicting fall status: perception of postural instability, balance performance, and executive function processing speed. The results support prior work in both nonclinical and clinical populations of middle aged and older adults indicating that falls are associated with multiple risk factors. Prospective designs with larger samples are needed to (a) validate and extend these findings, and (b) identify risk factors related to fall status that are unique to persons with FM. © 2010 Wiley Periodicals, Inc. Res Nurs Health 33:192,206, 2010 [source] The stability of AQT processing speed, ADAS-Cog and MMSE during acetylcholinesterase inhibitor treatment in Alzheimer's diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 3 2010E. H. Wiig Wiig EH, Annas P, Basun H, Andreasen N, Lannfelt L, Zetterberg H, Blennow K, Minthon L. The stability of AQT processing speed, ADAS-Cog and MMSE during acetylcholinesterase inhibitor treatment in Alzheimer's disease. Acta Neurol Scand: 2010: 121: 186,193. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives,,, To explore the longitudinal stability of measures of cognition during treatment with acetylcholinesterase inhibitors (AchEI) in patients with Alzheimer's disease (AD). Materials and methods,,, Cognitive status was measured in a cohort of 60 patients at 6 months after initiation of treatment with AchEI (baseline) and after an additional 6 months of treatment (endpoint). A Quick Test of Cognitive Speed (AQT), Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), and MMSE were administered concurrently. Results,,, Correlations (,) between age and AQT processing speed were non-significant, but were significant for ADAS-Cog and Mini Mental State Examination (MMSE). AQT and ADAS-Cog means did not differ significantly between baseline and endpoint. There was a small, significant reduction in MMSE point scores. Measures of stability (Spearman's ,) were moderate-to-high for all tests. Means for subgroups did not differ as a function of medication type. Conclusions,,, AQT processing speed, ADAS-Cog, and MMSE measures proved stable during the second 6 months of treatment with AChEI. [source] The influence of cognitive impairment on health-related quality of life in neurological diseaseACTA NEUROPSYCHIATRICA, Issue 1 2010Alex J. Mitchell Mitchell AJ, Kemp S, Benito-León J, Reuber M. The influence of cognitive impairment on health-related quality of life in neurological disease. Background: Cognitive impairment is the most consistent neurological complication of acquired and degenerative brain disorders. Historically, most focus was on dementia but now has been broadened to include the important construct of mild cognitive impairment. Methods: Systematic search and review of articles linked quality of life (QoL) and cognitive complications of neurological disorders. We excluded QoL in dementia. Results: Our search identified 249 publications. Most research examined patients with brain tumours, stroke, epilepsy, head injury, Huntington's disease, motor neuron disease, multiple sclerosis and Parkinson's disease. Results suggested that the majority of patients with epilepsy, motor neuron disease, multiple sclerosis, Parkinson's disease, stroke and head injury have subtle cognitive deficits early in their disease course. These cognitive complaints are often overlooked by clinicians. In many cases, the cognitive impairment is progressive but it can also be relapsing-remitting and in some cases reversible. Despite the importance of severe cognitive impairment in the form of dementia, there is now increasing recognition of a broad spectrum of impairment, including those with subclinical or mild cognitive impairment. Even mild cognitive difficulties can have functional and psychiatric consequences,especially when they are persistent and untreated. Specific cognitive deficits such an inattention, dysexecutive function and processing speed may affect a number of quality of life (QoL) domains. For example, cognitive impairment influences return to work, interpersonal relationships and leisure activities. In addition, fear of future cognitive decline may also impact upon QoL. Conclusions: We recommend further development of simple tools to screen for cognitive impairments in each neurological condition. We also recommend that a thorough cognitive assessment should be a part of routine clinical practice in those caring for individuals with neurological disorders. [source] | ||||||||||||||||||||||||||||||||||