Cognitive dysfunction in patients with relapsing-remitting multiple sclerosis

2006 ◽  
Vol 12 (1) ◽  
pp. 77-87 ◽  
Author(s):  
U Nocentini ◽  
P Pasqualetti ◽  
S Bonavita ◽  
M Buccafusca ◽  
M F De Caro ◽  
...  

Cognitive dysfunction is considered one of the clinical markers of multiple sclerosis (MS). However, in the literature there are inconsistent reports on the prevalence of cognitive dysfunction, and separate data for the relapsing-remitting (RR) type of the disease are not always presented. In this study, we submitted 461 RRMS patients to a battery of neuropsychological tests to investigate their impairment in various cognitive domains. As a consequence of the exclusion criteria, the sample is not fully representative of the entire population of RRMS patients. In this selected sample, when only the eight scores of a core battery (Mental Deterioration Battery) were considered (with respective cutoffs), it emerged that 31% of the patients were affected by some degree of cognitive deficit. In particular, 15% had mild, 11.2% moderate and 4.8% had severe impairment. Information processing speed was the most frequently impaired area, followed by memory. When two other tests (SDMT and MCST) were added and cognitive domains were considered, it emerged that 39.3% of the patients were impaired in two or more domains. When four subgroups were obtained by means of cluster analysis and then compared, it emerged that information processing speed and memory deficits differentiated the still cognitively unimpaired from the mildly impaired MS patients. Significant associations were found between cognitive and clinical characteristics. However, due to the large sample size, clinically irrelevant relationships may also have emerged. Even with the limitations imposed by the sample selection and the possible underestimation of the prevalence and severity of cognitive dysfunction, these results seem to provide further evidence that information processing speed deficit may be an early and important marker of cognitive impairment in MS patients.

2014 ◽  
Vol 20 (11) ◽  
pp. 1453-1463 ◽  
Author(s):  
Magdalena Wojtowicz ◽  
Erin L Mazerolle ◽  
Virender Bhan ◽  
John D Fisk

Background: Patients with multiple sclerosis (MS) demonstrate slower and more variable performance on attention and information processing speed tasks. Greater variability in cognitive task performance has been shown to be an important predictor of neurologic status and provides a unique measure of cognitive performance in MS patients. Objectives: This study investigated alterations in resting-state functional connectivity associated with within-person performance variability in MS patients. Methods: Relapsing–remitting MS patients and matched healthy controls completed structural MRI and resting-state fMRI (rsfMRI) scans, as well as tests of information processing speed. Performance variability was calculated from reaction time tests of processing speed. rsfMRI connectivity was investigated within regions associated with the default mode network (DMN). Relations between performance variability and functional connectivity in the DMN within MS patients were evaluated. Results: MS patients demonstrated greater reaction time performance variability compared to healthy controls ( p<0.05). For MS patients, more stable performance on a complex processing speed task was associated with greater resting-state connectivity between the ventral medial prefrontal cortex and the frontal pole. Conclusions: Among MS patients, greater functional connectivity between medial prefrontal and frontal pole regions appears to facilitate performance stability on complex speed-dependent information processing tasks.


1994 ◽  
Vol 78 (3) ◽  
pp. 883-887 ◽  
Author(s):  
Jim Grigsby ◽  
Kathryn Kaye ◽  
David Busenbark

Alphanumeric Sequencing involves the alternating recitation of counting and the alphabet. We report data on the use of this measure with two clinical samples of persons with multiple sclerosis, having either the chronic progressive (n = 23) or relapsing-remitting form (n = 52) of the disease. Patients were administered Alphanumeric Sequencing and several other tests of information-processing speed/capacity and short-term memory. Chronic progressive MS patients performed worse than 23 healthy controls on both the speed and error components of the test, while relapsing-remitting patients were worse than 35 controls only on the total time to complete the task. The time score was correlated with several measures of information processing and short-term memory.


2013 ◽  
Vol 19 (5) ◽  
pp. 551-558 ◽  
Author(s):  
Magdalena Wojtowicz ◽  
Antonina Omisade ◽  
John D. Fisk

AbstractImpairments in attention and information processing speed are common in multiple sclerosis (MS) and may contribute to impairments of other cognitive abilities. This study examined attentional efficiency, information processing speed and intra-individual variability in response speed using the Attention Network Test-Interactions (ANT-I) in mildy-affected patients with MS. Thirty-one patients with relapsing-remitting MS and 30 age, sex, and education-matched controls completed the ANT-I, as well as the Paced Auditory Serial Attention Test (PASAT), as a standard clinical measure of information processing efficiency. As expected, patients with MS were slower in reaction time performance on the ANT-I and had poorer performance on the PASAT compared to controls. Patients with MS also demonstrated poorer efficiency in their executive control of attention on the ANT-I, suggesting difficulties with top-down allocation of attention. In addition, the MS group demonstrated greater intra-individual variability in the responses to the ANT-I even when their slower overall response time and other factors such as practice were accounted for. Intra-individual variability was found to best predict group membership compared to PASAT scores and other ANT-I scores. These results suggest that intra-individual variability may provide sensitive, unique and important information regarding cognitive functioning in early MS. (JINS, 2013, 19, 1–8)


2013 ◽  
Vol 19 (5) ◽  
pp. 613-620 ◽  
Author(s):  
Emily M. Owens ◽  
Douglas R. Denney ◽  
Sharon G. Lynch

AbstractPrevious studies show that MS patients take longer than healthy controls to plan their solutions to Tower of London (TOL) problems but yield conflicting results regarding the quality of their solutions. The present study evaluated performance under untimed or timed conditions to assess the possibility that differences in planning ability only occur when restrictions in solution times are imposed. MS patients (n = 39) and healthy controls (n = 43) completed a computerized version of the TOL under one of two conditions. In the untimed condition, participants were allowed as much time as needed on each problem. In the timed condition, limits were imposed on solution times and time remaining was displayed with each problem. Patients exhibited longer planning times than controls, and the disparity between groups increased with problem difficulty. Planning performance depended upon condition. In the untimed condition, patients and controls performed equally well. When solution times were restricted, however, patients solved fewer problems than controls. MS patients’ planning ability is intact when permitted sufficient time to formulate the required plan. Deficiencies in planning are only evident when time is restricted, and, therefore, are more accurately considered a relative consequence of disease-related problems in information processing speed. (JINS, 2013, 19, 1–8)


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