Attention In Multiple Sclerosis Research Articles

Preliminary evidence that caffeine improves attention in multiple sclerosis

There are no licensed drugs to boost cognitive performance in multiple sclerosis (MS). Here, we provide preliminary evidence that caffeine can improve attention in people with MS. Participants were tested on three different metrics of attentional functioning [choice reaction times, Stroop performance and a Rapid Serial Visual Presentation (RSVP) task] repeated across four sessions (baseline, one week after caffeine abstention and two sessions on days 8 and 9 where participants were pseudorandomized to receive counterbalanced caffeine or decaffeinated products). The administration of caffeine, compared to decaffeinated substances, was found to selectively reduce the ‘attentional blink’ in MS patients. There was no evidence that caffeine administration significantly affected performance on the Stroop or choice reaction time tasks. However, in contrast to other metrics of attention used in this study, there was evidence that Stroop performance declined on day 7 compared to day 1, an effect perhaps due to caffeine withdrawal. Cumulatively, these results suggest that caffeine can act as a cognitive enhancer in MS but may only benefit patients under situations of high attentional demand (RSVP dual task). Interestingly, there may be long-term positive effects of caffeine on cognition in MS that are only exposed following sustained abstinence periods.

Computer Aided Diagnosis System for multiple sclerosis disease based on phase to amplitude coupling in covert visual attention

Background and objectiveComputer Aided Diagnosis (CAD) techniques have widely been used in research to detect the neurological abnormalities and improve the consistency of diagnosis and treatment in medicine. In this study, a new CAD system based on EEG signals was developed. The motivation for the development of the CAD system was to diagnose multiple sclerosis (MS) disease during covert visual attention tasks. It is worth noting that research of this kind on the efficacy of attention tasks is limited in scope for MS patients; therefore, it is vital to develop a feature of EEG to characterize the patient's state with high sensitivity and specificity. MethodsWe evaluated the use of phase–amplitude coupling (PAC) of EEG signals to diagnose MS. It is assumed that the role of PAC for information encoding during visual attention in MS is greatly unknown; therefore, we made an attempt to investigate it via CAD systems. The EEG signals were recorded from healthy and MS patients while performing new visual attention tasks. Machine learning algorithms were also used to identify the EEG signals as to whether the disease existed or not. The challenge regarding the dimensionality of the extracted features was addressed through selecting the relevant and efficient features using T-test and Bhattacharyya distance criteria, and the validity of the system was assessed through leave-one-subject-out cross-validation method. ResultsOur findings indicated that online sequential extreme learning machine (OS-ELM) classifier with T-test feature selection method yielded peak accuracy, sensitivity and specificity in both color and direction tasks. These values were 91%, 83% and 96% for color task, and 90%, 82% and 96% for the direction task. ConclusionsBased on the results, it can be concluded that this procedure can be used for the automatic diagnosis of early MS, and can also facilitate the treatment assessment in patients.

Multiple Sclerosis: Left Advantage for Auditory Laterality in Dichotic Tests of Central Auditory Processing and Relationship of Psychoacoustic Tests With the Multiple Sclerosis Disability Scale-EDSS

ObjectiveTo evaluate the central auditory processing disorders in patients with multiple sclerosis, emphasizing auditory laterality by applying psychoacoustic tests and to identify their relationship with the Multiple Sclerosis Disability Scale (EDSS) functions. MethodDepression scales (HADS), EDSS, and 9 psychoacoustic tests to study CAPD were applied to 26 individuals with multiple sclerosis and 26 controls. Correlation tests were performed between the EDSS and psychoacoustic tests. ResultsSeven out of 9 psychoacoustic tests were significantly different (P<.05); right or left (14/19 explorations) with respect to control. In dichotic digits there was a left-ear advantage compared to the usual predominance of RDD. There was significant correlation in five psychoacoustic tests and the specific functions of EDSS. ConclusionThe left-ear advantage detected and interpreted as an expression of deficient influences of the corpus callosum and attention in multiple sclerosis should be investigated. There was a correlation between psychoacoustic tests and specific EDSS functions.

Evidence of attentional impairments using virtual driving simulation in multiple sclerosis

BackgroundDetection of attentional disorders in complex situation related to daily life activities in multiple sclerosis patients needs better adapted tools than traditional cognitive assessment. ObjectiveTo investigate the usefulness of virtual reality assessment of attention in multiple sclerosis, especially to evaluate alertness and divided attention using driving simulation. MethodsIn this preliminary study, 11 relapsing-remitting patients (median EDSS: 2; mean disease duration of 10.3 years) and 11 healthy matched controls performed a driving simulation under three conditions (monotonous driving, divided attention driving and urban driving) where Standard Deviation of Lateral position (SDLP) was the main evaluated criteria. In comparison, traditional cognitive assessment of attentional functions was administered (SDMT, alertness and divided attention of TAP battery). Statistical non-parametric Mann-Whitney U tests were used to compare performances between groups in the two types of assessments. Exploratory correlational analyses were further conducted. ResultsNo significant difference was observed between groups for traditional attentional assessment except for information processing speed (SDMT; p < 0.01). Considering virtual reality, patients were less efficient than controls on the primary parameter of safe driving (SDLP; p < 0.05). They also committed more errors and omissions (p < 0.01) and speed fluctuations (p < 0.01) during the divided-attention driving condition. Urban driving did not reveal difference between groups. Lack of significant correlations between traditional and virtual reality attentional assessment suggested that they do not evaluate the same cognitive processes. ConclusionPatients experienced difficulties in maintaining the trajectory and the speed of the simulated vehicle which may be indicative of attentional difficulties, especially alertness and divided attention. These impairments were not revealed by the traditional cognitive assessment. Results of this preliminary study shed new light about the usefulness of virtual reality techniques and their future interest as a part of cognitive rehabilitation programs. They also highlights the need to develop driving preventive measures in MS.

Esclerosis múltiple: ventaja izquierda para la lateralidad auditiva en pruebas dicóticas de procesamiento auditivo central y relación de pruebas psicoacústicas con examen de discapacidad-EDEM

ObjectiveTo evaluate the central auditory processing disorders in patients with multiple sclerosis, emphasizing auditory laterality by applying psychoacoustic tests and to identify their relationship with the Multiple Sclerosis Disability Scale (EDSS) functions. MethodDepression scales (HADS), EDSS, and 9 psychoacoustic tests to study CAPD were applied to 26 individuals with multiple sclerosis and 26 controls. Correlation tests were performed between the EDSS and psychoacoustic tests. ResultsSeven out of 9 psychoacoustic tests were significantly different (P<.05); right or left (14/19 explorations) with respect to control. In dichotic digits there was a left-ear advantage compared to the usual predominance of RDD. There was significant correlation in five psychoacoustic tests and the specific functions of EDSS. ConclusionThe left-ear advantage detected and interpreted as an expression of deficient influences of the corpus callosum and attention in multiple sclerosis should be investigated. There was a correlation between psychoacoustic tests and specific EDSS functions.

Effects of transcranial random noise stimulation (tRNS) on affect, pain and attention in multiple sclerosis.

Pain and cognitive impairment are frequent symptoms in patients with multiple sclerosis (MS). Neglecting experimental pain and paying attention to demanding tasks is reported to decrease the pain intensity. Little is known about the interaction between chronic neuropathic pain and attention disorders in MS. Recently, transcranial direct current stimulation (tDCS) was used to modulate various cognitive and motor symptoms in MS. We aimed to study the effects of transcranial random noise stimulation (tRNS), a form of transcranial electric stimulation, over the left dorsolateral prefrontal cortex (DLPFC) on attention and neuropathic pain in MS patients. 16 MS patients were included in a randomized, sham-controlled, cross-over study. Each patient randomly received two tRNS blocks, separated by three weeks of washout interval. Each block consisted of three consecutive daily sessions of either active or sham tRNS. The patients were evaluated for pain, attention and mood and further underwent an electrophysiological evaluation. Compared to sham, tRNS showed a trend to decrease the N2-P2 amplitudes of pain related evoked potentials and improve pain ratings. Attention performance and mood scales did not change after stimulations. This study suggests the role of tRNS in pain modulation, which could have been more evident with longer stimulation protocols.

ID 207 – The effects of tDCS on pain and attention in multiple sclerosis

Objective Pain and attentional deficit are frequent symptoms in patients with multiple sclerosis (MS), yet little is known about their interaction in this context. Here, we studied the effects of transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (DLPFC), which plays a key role in pain and attentional circuits. Methods Twenty painful MS patients were included in a randomized, sham-controlled, cross-over study. Participants randomly received two tDCS blocks, each consisting of three consecutive daily sessions of either active anodal or sham tDCS, separated by three weeks of washout interval. Cognitive, neuropsychological and electrophysiologic evaluations were performed. Results Compared to sham, active tDCS significantly improved pain, and had a trend in ameliorating the alerting network of attention. No correlations were found between both improvements. The stimulation neither improved the remaining attentional networks, nor significantly affected the other variables. Conclusions tDCS over the DLPFC improves pain and attention in MS patients. Such an effect seems to occur by two independent mechanisms of action. Key Message tDCS over the DLPFC can improve pain and attention in MS patients.

Spatial attention in multiple sclerosis

Spatial attention in multiple sclerosis

Information processing speed and attention in multiple sclerosis: Reconsidering the Attention Network Test (ANT)

Objective: The Attention Network Test (ANT) assesses attention in terms of discrepancies between response times to items that differ in the burden they place on some facet of attention. However, simple arithmetic difference scores commonly used to capture these discrepancies fail to provide adequate control for information processing speed, leading to distorted findings when patient and control groups differ markedly in the speed with which they process and respond to stimulus information. This study examined attention networks in patients with multiple sclerosis (MS) using simple difference scores, proportional scores, and residualized scores that control for processing speed through statistical regression. Method: Patients with relapsing-remitting (N = 20) or secondary progressive (N = 20) MS and healthy controls (N = 40) of similar age, education, and gender completed the ANT. Results: Substantial differences between patients and controls were found on all measures of processing speed. Patients exhibited difficulties in the executive control network, but only when difference scores were considered. When deficits in information processing speed were adequately controlled using proportional or residualized score, deficits in the alerting network emerged. The effect sizes for these deficits were notably smaller than those for overall information processing speed and were also limited to patients with secondary progressive MS. Conclusions: Deficits in processing speed are more prominent in MS than those involving attention, and when the former are properly accounted for, differences in the latter are confined to the alerting network.

Memory and selective attention in multiple sclerosis: cross-sectional computer-based assessment in a large outpatient sample.

Cognitive impairments may have a severe impact on everyday functioning and quality of life of patients with multiple sclerosis (MS). However, there are some methodological problems in the assessment and only a few studies allow a representative estimate of the prevalence and severity of cognitive impairments in MS patients. We applied a computer-based method, the memory and attention test (MAT), in 531 outpatients with MS, who were assessed at nine neurological practices or specialized outpatient clinics. The findings were compared with those obtained in an age-, sex- and education-matched control group of 84 healthy subjects. Episodic short-term memory was substantially decreased in the MS patients. About 20% of them reached a score of only less than two standard deviations below the mean of the control group. The episodic short-term memory score was negatively correlated with the EDSS score. Minor but also significant impairments in the MS patients were found for verbal short-term memory, episodic working memory and selective attention. The computer-based MAT was found to be useful for a routine assessment of cognition in MS outpatients.

Health literacy association with health behaviors and health care utilization in multiple sclerosis: a cross-sectional study.

BackgroundLow health literacy is generally associated with poor health outcomes; however, health literacy has received little attention in multiple sclerosis (MS).ObjectiveThe aim of this study was to investigate the health literacy of persons with MS using the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry.MethodsIn 2012, we conducted a cross-sectional study of health literacy among NARCOMS participants. Respondents completed the Medical Term Recognition Test (METER) which assesses the ability to distinguish medical and nonmedical words, and the Newest Vital Sign (NVS) instrument which evaluates reading, interpretation, and numeracy skills. Respondents reported their sociodemographic characteristics, health behaviors, comorbidities, visits to the emergency room (ER), and hospitalizations in the last 6 months. We used logistic regression to evaluate the characteristics associated with functional literacy, and the association between functional literacy and health care utilization.ResultsOf 13,020 eligible participants, 8934 (68.6%) completed the questionnaire and were US residents. Most of them performed well on the instruments with 81.04% (7066/8719) having functional literacy on the METER and 74.62% (6666/8933) having adequate literacy on the NVS. Low literacy on the METER or the NVS was associated with smoking, being overweight or obese (all P<.001). After adjustment, low literacy on the METER was associated with ER visits (OR 1.28, 95% CI 1.10-1.48) and hospitalizations (OR 1.19, 95% CI 0.98-1.44). Findings were similar for the NVS.ConclusionsIn the NARCOMS cohort, functional health literacy is high. However, lower levels of health literacy are associated with adverse health behaviors and greater health care utilization.

Revisiting the role of B cells in multiple sclerosis: Regulatory B cell function and defects in peripheral B cell tolerance

The role of B cells in multiple sclerosis pathogenesis is being increasingly recognized. Although B cells certainly play a critical role in adaptive immunity through antibody secretion, what has received a lot of attention in multiple sclerosis is the antibody-independent B cell functions.

Patterns of retinal nerve fiber layer loss in multiple sclerosis patients with or without optic neuritis and glaucoma patients

Objective Optical coherence tomography (OCT) has gained increasing attention in multiple sclerosis (MS) research and has been suggested as outcome measure for neuroprotective therapies. However, to date it is not clear whether patterns of retinal nerve fiber layer thickness (RNFLT) loss are different in MS compared to other diseases such as glaucoma and data on RNFLT loss in MS patients with or without optic neuritis (ON/NON) have remained inconsistent or even contradictory. Methods In this large cross-sectional study we analyzed the patterns of axonal loss of retinal ganglion cells in MS eyes ( n = 262) with and without history of ON (MS/ON: 73 eyes; MS/NON: 189 eyes) and patients eyes with glaucomatous optic disc atrophy (GA: n = 22; 39 eyes) in comparison to healthy control eyes (HC: n = 406 eyes). Results We found that significant average and quadrant RNFLT loss is detectable by OCT in both MS and GA patients compared to healthy controls ( p < 0.01). The age- and gender adjusted average and quadrant RNFLT did not differ significantly between MS and GA patients ( p > 0.05). Average ( p < 0.0001) and quadrant ( p < 0.05) RNFL thinning is significantly more severe in MS/ON versus MS/NON eyes, and the extent of RNFL thinning varies across quadrants in MS/ON eyes with the highest degree of RNFLT loss in the temporal quadrant ( p < 0.001). Conclusion RNFLT reduction across all four quadrants in MS patients as a whole as well as in MS/NON eyes argues for a diffuse neurodegenerative process. Superimposed inflammatory attacks to the optic nerve may cause additional axonal damage with a temporal preponderance. Future studies are necessary to further evaluate the capacity of OCT to depict disease specific damage patterns.

High frequency of adverse health behaviors in multiple sclerosis

Background Health behaviors influence chronic disease risks in the general population, and may influence health outcomes independently of comorbid diseases. Health behaviors receive less attention in multiple sclerosis (MS) than in the general population. We assessed health behaviors among participants in the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry and the demographic characteristics associated with particular health behaviors. Methods In October 2006, we surveyed NARCOMS participants regarding smoking using questions from the Behavioral Risk Factor Surveillance Survey; physical activity using questions from the PEPI study, alcohol use using the AUDIT-C; and height and weight. To determine the independent demographic predictors of health behaviors, we used multivariable logistic regression, either binary or polytomous as appropriate. Results Of 8983 responders, 4867 (54.2%) ever smoked; 1542 (17.3%) currently smoked. On the basis of the AUDIT-C, 1632 (18.2%) were at risk for alcohol abuse or dependence. A quarter of participants were obese (n = 2269), and 2780 (31.3%) were overweight. Fewer than 25% of participants reported moderate or heavy leisure-time physical activity. Generally, lower socioeconomic status was associated with a higher frequency of adverse health behaviors accounting for other demographic factors. With increasing levels of disability, the reported intensity of physical activity was lower, and the frequency of overweight or obesity was higher. Conclusions Patients with MS exhibit frequent adverse health behaviors, increasing the risk of other chronic diseases. Further research is needed to determine how these behaviors influence disability progression, quality of life, and other MS-related outcomes.

Cortical recruitment during selective attention in multiple sclerosis: An fMRI investigation of individual differences

Recent studies with multiple sclerosis (MS) participants have provided evidence for cortical reorganization. Greater recruitment of task-related areas and additional brain regions are thought to play an adaptive role in the performance of cognitive tasks. In this study, we compared cortical circuitry recruited by MS patients and controls during a selective attention task that requires both focusing attention on task-relevant information and ignoring or inhibiting task-irrelevant information. Despite comparable behavioral performance, MS patients demonstrated increased neural recruitment of task-related areas along with additional activation of the prefrontal cortices. However, this additional activation was associated with poor behavioral performance, thereby providing evidence against compensatory brain reorganization. Future studies specifically investigating the nature of additional activation seen in MS patients in a wider variety of cognitive tasks would provide insight into the specific cognitive decline in MS.

Retraining attention in MS

Cognitive decline is frequently observed in multiple sclerosis (MS) and has a major impact on quality of life. Therefore it would be important to offer therapeutic strategies to the patients. In the past, several studies were conducted on pharmacological or cognitive treatment. However, there is currently no specific treatment for cognitive decline and the studies published so far report heterogeneous results. The present paper focuses on the cognitive treatment strategies by reviewing and discussing the few studies that have been carried out in this area. In addition, results of a recently completed fMRI study on the visualization of cognitive training effects will be reported. This review clearly points out that further research in this area is needed to clarify the effects of cognitive intervention. Larger sample sizes and standardized neuropsychological outcome measures as well as standardized training tools are required to allow for comparisons between different studies and to improve our understanding of cognitive decline and the processes of cognitive recovery in MS.

Functional imaging during covert auditory attention in multiple sclerosis

Recent literature suggests that the brain in multiple sclerosis (MS) undergoes reorganization that subserves the performance of visual and motor tasks. We identified sites of cerebral activity in 16 MS patients while performing a covert attention (CA) task, presented in the auditory modality. Positron emission tomography (PET) revealed activation of rostral/dorsal anterior cingulate cortex (ACC) in normal subjects studied previously. Activity in this region was not significant in MS patients, but there was a large region of activity in superior temporal cortex. Decreased activation of frontal attentional networks and greater activity in sensory/perceptual cortical areas (auditory association cortex) suggests a reduction of transmission along white matter tracts connecting these regions. This study demonstrates cingulate hypoactivity and cerebral reorganization during auditory attention in MS.

Reliability and validity of the Multiple Sclerosis Quality of Life Inventory in older individuals

Purpose: Despite the increasing number of older individuals with multiple sclerosis (MS), there is a paucity of research on this subpopulation. Health-related quality of life (HRQOL) has received extensive attention in MS; however samples tend to be young. The present study assesses the internal consistency reliability and construct validity of the MS Quality of Life Inventory (MSQLI), a widely employed measure of HRQOL, in older individuals. Method: Select subscales of the MSQLI and other measures of mental health and physical functioning were administered by telephone to 30 randomly selected older ( ⩾̸ 60) individuals and a gender-matched sample of younger ( < 60) individuals. Reliability estimates were calculated separately for each group. Construct (convergent) validity was assessed by examining the pattern of correlations between MSQLI subscales and measures of related constructs in the two groups. Results: Reliability estimates were similar in the two groups. With few exceptions, the correlations measuring convergent validity were in the expected direction, and of considerable magnitude, in both groups Conclusions: Results provide preliminary evidence that the MSQLI is a reliable and valid instrument for use with older individuals. The slightly different pattern of results observed in the validity analysis might be explained by an adjustment hypothesis. Future research on HRQOL in this subpopulation is encouraged.

The Ecological Validity of Clinical Tests of Memory and Attention in Multiple Sclerosis

Ecological validity—the degree to which clinical tests of cognitive functioning predict functional impairment—has recently become an area of interest in neuropsychology. The current study used a sample of 31 cognitively and functionally impaired multiple sclerosis (MS) patients to determine if tests commonly used to assess memory and attentional functioning in MS are ecologically valid. Two methods of improving the ecological validity of cognitive testing were employed. Stepwise multiple regression analyses suggested that tests of memory and attention more analogous to everyday tasks are better predictors of functional impairment in MS than both standard clinical tests of memory and attention, and memory questionnaires completed by the patient or a significant other. Nonetheless, both standard clinical tests and more ecologically valid tests significantly predicted functional impairment. Importantly, they were not significantly correlated with one another, suggesting that the inclusion of both types of tests in evaluating MS patients is warranted. Keywords: ecological validity, multiple sclerosis, memory, attention

The Ecological Validity of Clinical Tests of Memory and Attention in Multiple Sclerosis

Ecological validity--the degree to which clinical tests of cognitive functioning predict functional impairment--has recently become an area of interest in neuropsychology. The current study used a sample of 31 cognitively and functionally impaired multiple sclerosis (MS) patients to determine if tests commonly used to assess memory and attentional functioning in MS are ecologically valid. Two methods of improving the ecological validity of cognitive testing were employed. Stepwise multiple regression analyses suggested that tests of memory and attention more analogous to everyday tasks are better predictors of functional impairment in MS than both standard clinical tests of memory and attention, and memory questionnaires completed by the patient or a significant other. Nonetheless, both standard clinical tests and more ecologically valid tests significantly predicted functional impairment. Importantly, they were not significantly correlated with one another, suggesting that the inclusion of both types of tests in evaluating MS patients is warranted.