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Cognitive conflict effects are well characterized within unimodality. However, little is known about cross-modal conflicts and their neural bases. This study characterizes the two types of visual and auditory cross-modal conflicts through working memory tasks and brain activities. The participants consisted of 31 healthy, right-handed, young male adults. The Paced Auditory Serial Addition Test (PASAT) and the Paced Visual Serial Addition Test (PVSAT) were performed under distractor and no distractor conditions. Distractor conditions comprised two conditions in which either the PASAT or PVSAT was the target task, and the other was used as a distractor stimulus. Additionally, oxygenated hemoglobin (Oxy-Hb) concentration changes in the frontoparietal regions were measured during tasks. The results showed significantly lower PASAT performance under distractor conditions than under no distractor conditions, but not in the PVSAT. Oxy-Hb changes in the bilateral ventrolateral prefrontal cortex (VLPFC) and inferior parietal cortex (IPC) significantly increased in the PASAT with distractor compared with no distractor conditions, but not in the PVSAT. Furthermore, there were significant positive correlations between Δtask performance accuracy and ΔOxy-Hb in the bilateral IPC only in the PASAT. Visual cross-modal conflict significantly impairs auditory task performance, and bilateral VLPFC and IPC are key regions in inhibiting visual cross-modal distractors. [ABSTRACT FROM AUTHOR]

Research ObjectivesImpairments in attention and the speed of information processing are central to the experience of cognitive fatigue in patients with acquired brain injury (ABI). Attention may be improved through intensive training in a rehabilitation setting. The aim of the study was to investigate the feasibility of reducing cognitive fatigability (CF) using attention training and to explore the effect of two different approaches to attention training.DesignRandomised controlled study in a rehabilitation setting.Participants59 patients (age 19–59 years) with mild to moderate stroke or traumatic brain injury in the early (

Research Objectives: Impairments in attention and the speed of information processing are central to the experience of cognitive fatigue in patients with acquired brain injury (ABI). Attention may be improved through intensive training in a rehabilitation setting. The aim of the study was to investigate the feasibility of reducing cognitive fatigability (CF) using attention training and to explore the effect of two different approaches to attention training. Design: Randomised controlled study in a rehabilitation setting. Participants: 59 patients (age 19–59 years) with mild to moderate stroke or traumatic brain injury in the early (<4 month) phase. Interventions: Patients were randomly assigned to intensive specific training with Attention Process Training (APT) or Activity-Based Attention Training (ABAT) for 3–5 days per week for a period of 5–6 weeks with a total of 20 h, in addition to traditional interdisciplinary rehabilitation. Main Outcome Measure: CF was conceptualised as performance decline in terms of an increased number of incorrect responses between the first and the last quintiles of the Paced Auditory Serial Addition Test (PASAT). A negative result was defined as fatigability. The evaluator of fatigability was blinded to treatment. Results: At baseline, there were no differences between the groups in age, education, reasoning, anxiety or depression. After training, a significant treatment effect was found (p = 0.020), as the APT-group, but not the ABAT-group, had improved. However, after controlling for baseline differences regarding CF on the PASAT-f, the difference was no longer significant. Conclusion: The results indicate that cognitive training might be a feasible method for reducing CF through attention training and that patients with high levels of CF benefit most from attention training. The type of intervention provided, whether specific or activity-based attention training, appears to be of less importance, as there was no treatment effect after controlling for the baseline level of CF. Future studies are required to confirm the validity of the findings. [ABSTRACT FROM AUTHOR]

Objective:The Paced Auditory Serial Addition Test (PASAT) is frequently employed to measure executive functions in patients with Multiple Sclerosis (MS). In the past, the PASAT has often been criticized because of its stressful and demanding requirements. Continuous utilization might also reduce its validity. The Five-Point Test (FPT) by Regard, Strauss, and Knapp ((1982) Children’s production on verbal and non-verbal fluency tasks.Perceptual and Motor Skills, 55, 839–844.) is a short test of figural fluency which might serve as a substitute.Method:116 patients diagnosed with MS were tested with a short version of the Brief Repeatable Battery (BRB) by Rao and the Cognitive Function Study Group of the National Multiple Sclerosis Society including the PASAT, as well as the FPT. A factor analysis was computed and the frequency of cognitive impairment was calculated for both the original short version of the BRB and the alternative version (involving the FPT).Results:In the factor analysis, PASAT and FPT loaded highest on the same factor (two factors were extracted). The estimation of the frequency of cognitive impairment showed that replacing the PASAT with the FPT did not considerably alter the proportion of patients identified as cognitively impaired.Conclusions:The FPT proved to be a viable alternative to the PASAT in this study. It may be recommended as a possible replacement in neuropsychological screening of MS-patients with the advantage of avoiding the indicated limitations of the PASAT. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive review of the literature on the neurocognitive impact of posttraumatic stress disorder (PTSD) and reports on a quantitative single-case study, which investigated whether eye movement desensitization and reprocessing (EMDR) therapy would change the neuropsychological and physiological responses of an 18-year-old female client diagnosed with comorbid PTSD and major depressive disorder. Eleven 90-minute weekly sessions of EMDR therapy were provided. We used biofeedback equipment (ProComp5 Infiniti System) to obtain records of heart rate and conductance while the participant was in the desensitization and reprocessing phases of EMDR therapy. Results showed a heart rate decrease between baselines at the beginning and end of treatment. Neuropsychological evaluations of attention, memory, and brain executive functions showed pretreatment impairments in attentional processes, information processing speed, and working memory and posttreatment improvement of these cognitive functions, with significant differences on the Paced Auditory Serial Addition Test. We found a substantial posttreatment decrease in mean scores on the Beck Depression Inventory-ll and the Dissociative Experiences Scale. Furthermore, the patient showed no signs of PTSD after the intervention, based on the Posttraumatic Stress Global Scale. At 1-year follow-up, the participant reported maintenance of treatment effects. We discuss how amelioration of PTSD symptoms was associated with improved neurocognitive outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To determine whether there is an association between improvements in objective measures of physical fitness and performance on cognitive tests in people with multiple sclerosis (MS). Design: Post hoc correlational analysis in which people demonstrating physical improvement were compared with those not demonstrating physical improvement. Setting: Individuals with MS residing in the community. Participants: Adults with clinically confirmed MS (N=88) who participated in a controlled trial of a telephone-based health promotion intervention, chose to work on exercise, and completed the pre- and postintervention assessments. Interventions: Participants were measured for strength (isokinetic dynamometer), aerobic fitness (bicycle ergometer), and cognition (Paced Auditory Serial Addition Test [PASAT], Trail Making Test [TMT]) at baseline and 12 weeks later. Change in fitness was calculated by subtracting each participant's baseline score from the outcome score, and then transforming the difference to a z score. Individuals with a z score ≥1 on any fitness measure were placed in the physically improved group (n=25). All others were in the physically not improved group (n=57). Main Outcome Measures: TMT, PASAT. Results: After controlling for covariates (age, sex, ethnicity, education, disease activity, MS type), there was a significant group-by-time interaction, suggesting that cognitive functioning changed over time based on level of fitness. Participants in the physically improved group demonstrated improved performance on measures of executive functioning after 12 weeks of exercise. Conclusions: The results of this study lend support to the hypothesis that change in fitness is associated with improved executive functioning in people with MS. [Copyright &y& Elsevier]

Abstract: Objective: To determine the potential to improve driving-related skills using a simulator-based program in persons with relapsing-remitting multiple sclerosis (RRMS). Design: Pre-post intervention. Setting: A university driving simulator laboratory. Participants: Participants (N=50) with RRMS and Expanded Disability Status Scale (EDSS) scores between 1 and 7 were enrolled. Pre- and posttraining data from 36 participants (mean age ± SD, 46±11y; 30 women) who received training and 6 participants (mean age ± SD, 48±13y; 5 women) who did not receive training (control group) were compared. Interventions: Five hours of driving training in a simulator. Main Outcome Measures: Performance on a road test at pre- and posttraining. Secondary outcome measures were performance on visual, physical, and cognitive tests. Results: Overall, no significant differences were observed between the training and control groups before and after training. However, 4 of the 7 participants in the training group who failed the road test at pretraining passed posttraining, while the only participant in the control group who failed at pretraining still failed at posttraining. The training group also improved on perception of red and colored numbers, the Paced Auditory Serial Addition Test, and the dot cancellation test of the Stroke Driver Screening Assessment battery and reported less fatigue. These improvements were most pronounced among those with an EDSS score between 3 and 7. Conclusions: This pilot study demonstrates the potential of using a simulator to improve driving-related visual, cognitive, and on-road skills in individuals with RRMS, particularly those with an EDSS score >3. Future randomized controlled trials with adequate power are needed to expand this field of study. [Copyright &y& Elsevier]

Objective: We aimed to establish the thickness of retinal nerve fiber layer (RNFL) in multiple sclerosis (MS) patients and correlate it with disease disability, disease duration, physical and cognitive impairment. Methods: We studied 71 consecutive patients (142 eyes) with MS and proportionally matched 30 healthy controls (60 eyes). The thickness of RNFL was measured in both eyes by optical coherence tomography (OCT). Disease duration, Expanded Disability Status Scale (EDSS), Short Form-36 (SF-36), and Paced Auditory Serial Addition Test (PASAT) tests were examined in all patients. We investigated the correlations between RNFL and these parameters. Results: The average RNFL in MS patients was significantly lower compared with healthy controls (p:0.0001). We found no differences in the RNFL thickness between eyes with and without optic neuritis (p:0.448). The RNFL were significantly thinner in patients with EDSS >5.5 compared with group EDSS 0-2.5 (p:0.006). The RNFL thickness was significantly reduced with increasing of the disease duration (p:0.0001). The RNFL atrophy was significantly correlated with PASAT scores (p:0.0001). There was a low positive correlation between RNFL thickness and physical functioning as a parameter of SF-36 (p:0.031). Conclusion: We concluded that RNFL thinning is associated with disease duration and severity, and physical and cognitive impairment. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To examine associations between multitasking ability defined by performance on a complex task integrating multiple cognitive domains and vocational functioning in multiple sclerosis (MS). Design: Survey data collection. Setting: Laboratory with referrals from an outpatient clinic. Participants: Community-dwelling individuals with MS (N=30) referred between October 2011 and June 2012. Interventions: Not applicable. Main Outcome Measures: The modified Six Elements Test (SET) to measure multitasking ability, Fatigue Severity Scale to measure fatigue, several neuropsychological measures of executive functioning, and vocational status. Results: Among the sample, 60% of individuals have reduced their work hours because of MS symptoms (cutback employment group) and 40% had maintained their work hours. Among both groups, SET performance was significantly associated with performance on several measures of neuropsychological functioning. Individuals in the cutback employment group demonstrated significantly worse overall performance on the SET (P=.041). Logistic regression was used to evaluate associations between SET performance and vocational status, while accounting for neuropsychological performance and fatigue. The overall model was significant (χ2 3=8.65, P=.032), with fatigue [Exp(B)=.83, P=.01] and multitasking ability [Exp(B)=.60, P=.043] retained as significant predictors. Conclusions: Multitasking ability may play an important role in performance at work for individuals with MS. Given that multitasking was associated with vocational functioning, future efforts should assess the usefulness of incorporating multitasking ability into rehabilitation planning. [Copyright &y& Elsevier]

Abstract: Objective: To examine mobility, balance, fall risk, and cognition in older adults with multiple sclerosis (MS) as a function of fall frequency. Design: Retrospective, cross-sectional design. Setting: University research laboratory. Participants: Community-dwelling persons with MS (N=27) aged between 50 and 75 years were divided into 2 groups—single-time (n=11) and recurrent (n=16; >2 falls/12 mo) fallers—on the basis of fall history. Intervention: Not applicable. Main Outcome Measures: Mobility was assessed using a variety of measures including Multiple Sclerosis Walking Scale-12, walking speed (Timed 25-Foot Walk test), endurance (6-Minute Walk test), and functional mobility (Timed Up and Go test). Balance was assessed with the Berg Balance Scale, posturography, and self-reported balance confidence. Fall risk was assessed with the Physiological Profile Assessment. Cognitive processing speed was quantified with the Symbol Digit Modalities Test and the Paced Auditory Serial Addition Test. Results: Recurrent fallers had slower cognitive processing speed than single-time fallers (P≤.01). There was no difference in mobility, balance, or fall risk between recurrent and single-time fallers (P>.05). Conclusions: Results indicated that cognitive processing speed is associated with fall frequency and may have implications for fall prevention strategies targeting recurrent fallers with MS. [Copyright &y& Elsevier]

The PASAT, as a part of the Multiple Sclerosis Functional Composite, is used as a sole measure of cognition in multiple sclerosis (MS) clinical trials. In the present study, we evaluated the frequency and characteristics of cognitive impairment among relapsing-remitting MS patients. Using a comprehensive neuropsychological examination as the "golden standard," we assessed PASAT's sensitivity and specificity in MS-related cognitive impairment as well as factors possibly confounding PASAT performance. Forty-five relapsing-remitting MS patients and 48 healthy controls were studied using PASAT and a comprehensive neuropsychological examination. The frequency of cognitive dysfunction among MS patients was 42%. Cognitive impairment in MS was heterogeneous in nature but characterized, especially, by reduced information-processing ability and memory deficits. PASAT's sensitivity for patients' cognitive impairment was 74% and specificity 65%. Misclassification of cognitive impairment seemed to be associated with self-reported nervousness and poor arithmetic skills. Although PASAT offers satisfactory sensitivity in detecting the presence of cognitive impairment, its specificity may be limited by confounding factors. [ABSTRACT FROM AUTHOR]

The Paced Auditory Serial Addition Test (PASAT) is widely used in the evaluation of multiple sclerosis (MS) patients' cognitive performance, and also used as the sole measure of cognition in a recently developed assessment tool for MS clinical trials, the Multiple Sclerosis Functional Composite (MSFC). We analysed if MS patients and healthy controls have different patterns of responding in the PASAT, and whether different scoring methods influence the PASAT's sensitivity and specificity in detecting disease-associated cognitive impairment. Forty-five relapsing–remitting MS patients and 48 healthy controls were evaluated using the PASAT and a comprehensive neuropsychological examination. Cognitively deteriorated MS patients compensated for their difficulties in PASAT by omitting rather than guessing answers. They skipped items intermittently, which reduces the difficulty of the task. Furthermore, towards the end of the PASAT's 60-item series MS patients' performance had a trend to fade whereas controls' performance was more even throughout the task. The dyad score or the percent dyad score did not essentially improve the sensitivity or the specificity, but the accuracy improved when the answers at the end of the PASAT series were specifically emphasized. Using the combined score, 73% of the patients were correctly classified as cognitively impaired or unimpaired. [ABSTRACT FROM AUTHOR]