Language Functions in Patients with Multiple Sclerosis

Few studies have demonstrated language impairment in patients with multiple sclerosis (MS) compared to healthy controls. The purpose of this investigation was to examine language functions, specifically naming, comprehension, and verbal fluency, in patients with MS and healthy controls to (1) determine if patients with MS demonstrate language impairment, and (2) provide clarification of MS-related language disturbance, particularly in patients with MS of differing courses. Results showed that both chronic-progressive and relapsing-remitting patients with MS performed significantly more poorly than controls on naming, aural comprehension, letter fluency, and category fluency, as well as other language-based cognitive measures. Chronic-progressive patients obtained significantly lower scores than relapsing-remitting patients on the latter three tests. The language disturbance in this MS sample may be partly explained by impairment in other verbal cognitive functions. These findings highlight the importance of assessing language abilities in patients with MS.     

Use of the North American Adult Reading Test to estimate premorbid intellectual function in patients with multiple sclerosis.

The North American Adult Reading Test (NART-R) has proven to be a valid means of estimating premorbid intellectual function in a variety of neurologic patient samples. The NART-R was administered to a group of patients with multiple sclerosis (MS) varying in course and degree of physical disability and healthy controls as part of an extensive neuropsychological battery examining numerous verbal cognitive functions, particularly language. The MS sample demonstrated significantly worse NART-R performance than did controls which could not be explained by differences in estimated premorbid intellectual function. Patients with a chronic-progressive course specifically obtained significantly lower scores than did controls, whereas there were no differences in the scores obtained by patients with chronic-progressive and relapsing-remitting courses or by patients with a relapsing-remitting course and controls. Thus, NART-R performance may not be a valid estimate of baseline IQ for patients with neurologic disorders with suspected language impairment.     

Use of the North American Adult Reading Test to Estimate Premorbid Intellectual Function in Patients with Multiple Sclerosis

The North American Adult Reading Test (NART-R) has proven to be a valid means of estimating premorbid intellectual function in a variety of neurologic patient samples. The NART-R was administered to a group of patients with multiple sclerosis (MS) varying in course and degree of physical disability and healthy controls as part of an extensive neuropsychological battery examining numerous verbal cognitive functions, particularly language. The MS sample demonstrated significantly worse NART-R performance than did controls which could not be explained by differences in estimated premorbid intellectual function. Patients with a chronic-progressive course specifically obtained significantly lower scores than did controls, whereas there were no differences in the scores obtained by patients with chronic-progressive and relapsing-remitting courses or by patients with a relapsing-remitting course and controls. Thus, NART-R performance may not be a valid estimate of baseline IQ for patients with neurologic disorders with suspected language impairment.     

Cognitive impairment in amyotrophic lateral sclerosis: evidence from neuropsychological investigation and event-related potentials

The presence of subclinical cognitive impairment in patients with amyotrophic lateral sclerosis (ALS) is investigated using neuropsychological assessment and event-related potential recordings (ERP). An extensive battery of neuropsychological tests assessing the domains of attention, memory, language, visuo-spatial and executive functions were administered to 20 non-demented patients with sporadic ALS and 13 age- and education-matched healthy control subjects. Mismatch negativity (MMN), P3b, P3a (novelty P300) and contingent negative variation (CNV) were recorded. ALS patients were significantly impaired in tests of working memory, sustained attention, response inhibition, naming, verbal fluency and complex visuo-spatial processing. The memory impairment seemed to be secondary to deficits in forming learning strategies and retrieval. In ERP recordings, P3a and P3b amplitudes of ALS patients were lower compared with the controls, P3a latencies were significantly longer and mean CNV amplitudes were higher. These results indicate subclinical impairment of cognitive functions in patients with ALS. The pattern of cognitive impairment suggests the dysfunction of the frontal network.     

Fonctions cognitives sous-jacentes aux déficits de fluence verbale dans la schizophrénie : revue de la littérature

Individuals with schizophrenia usually show impairment on various cognitive functions, including long-term memory, executive functions and language. Compared to healthy controls, their performance is impaired in verbal fluency tests. These tests require participants to generate in a given time as many words as they can, belonging to a given category (semantic fluency), or beginning with a specific letter (orthographic fluency). Various cognitive functions are involved in verbal fluency tests: psychomotor speed, executive functions, language, long-term verbal memory and semantic memory. The purpose of the present study was to clarify the functional origin of verbal fluency deficits in schizophrenia through a literature review. Nineteen articles were selected in Pubmed and PsycINFO after initial screening and detailed review. They were formally analyzed with regard to general performance, cognitive strategies used in semantic and orthographic fluency tests and, underlying cognitive origin of deficits. Results show that individuals with schizophrenia produce fewer words than healthy controls in both types of fluency tests. Their impairment is more apparent in semantic than in orthographic fluency tests. Results of studies reviewed also show that individuals with schizophrenia adopt the same clustering (i.e. production of related words within a subcategory) and switching (i.e. ability to shift between clusters when a subcategory is exhausted) strategies than healthy controls, but less efficiently. Several hypotheses, such as the impairment of executive functions, semantic memory or speed of information processing, were put forward to account for this finding. Interestingly, the few studies in which researchers performed an analysis of the semantic relationships between words produced in fluency tests showed a less semantic coherence among people with schizophrenia than in healthy controls. Such a difference could be explained by disorganization of semantic memory or impairment in the activation of conceptual representations in semantic memory. Studies in which correlations and regression analyzes were performed allow for clarifying the cognitive origin underlying verbal fluency deficits in schizophrenia. The links between these deficits and information processing speed as well as working memory are well established. These two cognitive domains also appear to be strong predictors of performance in semantic and orthographic fluency tasks in schizophrenia. Individuals with schizophrenia usually present with a significant slowdown in the speed of information processing. Such a slowdown is likely to account for their poor performance in verbal fluency tests, which require the independent and rapid production of words. Working memory disorders are also core cognitive symptoms of schizophrenia. Working memory is involved in verbal fluency tests since they involve “strategic” activation of verbal information in long-term memory, inhibition of inappropriate words, switching between clusters, etc. However, the concept of working memory also partially encompasses the notion of executive functions so that the results reported in the present literature review, according to which impairment of verbal fluency in schizophrenia results from working memory deficits but not from executive functions deficits, are difficult to interpret. Results are also less clear-cut in regard to verbal long-term memory and to language abilities. Finally, numerous studies had shown that individuals with schizophrenia present specific deficits in the organization of semantic memory. However, the impact of this deficit on verbal fluency was explored in one study only. To conclude, verbal fluency tests are sensitive to various neurocognitive conditions and are helpful for differential diagnosis. Further studies are still needed to clarify the functional origin of verbal fluency deficits in schizophrenia, in particular the differential role of executive functions and working memory as well as the impact of semantic memory impairment.     

Effect of interferon-beta-1b on cognitive functions in multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is recognised as a central nervous system disease also affecting cognition. The rate of cognitive dysfunction in MS is in the range of 45-65% and adversely affect the quality of life. OBJECTIVE: To evaluate the effect of 1 year of treatment with interferon-beta-1b (IFNbeta-1b) on cognitive functions in patients suffering from relapsing-remitting MS. METHODS: A battery of cognitive tests was used to assess verbal learning, delayed recall, visual learning and recall, complex attention, concentration and verbal fluency at baseline and after 1 year of treatment with IFNbeta-1b. A group of 23 relapsing-remitting MS patients matched for neurological disability served as controls. RESULTS: Eighteen of 23 patients treated with IFNbeta-1b (74%) completed the study. In the IFNbeta-1b-treated group, complex attention, concentration as well as visual learning and recall improved significantly (p = 0.024, p = 0.006 and p = 0.005, respectively), while no deterioration was observed in the other dimensions. In the control group, complex attention, verbal fluency, as well as visual learning and recall deteriorated significantly (p = 0.02, p = 0.004 and p = 0.01, respectively), while no deterioration was observed in the other dimensions. CONCLUSION: Immunomodulating drugs that reduce the relapse rate and slow the disease progression also inhibit cognitive deterioration in patients with MS.     

Verbal fluency and executive dysfunction in amyotrophic lateral sclerosis (ALS)

Neuropsychological investigations of amyotrophic lateral sclerosis (ALS) patients have revealed variable results on specific tests, despite a similar overall cognitive profile of predominantly executive dysfunction with some evidence of memory impairment. The most striking and consistent deficit is found using tests of verbal fluency. The current investigation explored why verbal fluency is particularly sensitive to the impairment in ALS, by investigating some of the underlying cognitive processes: (i) intrinsic response generation; (ii) phonological loop functions; and (iii) simple word retrieval. Twenty-two ALS patients and 25 healthy controls were investigated. The battery included: (i) written and spoken letter-based fluency, category fluency, design fluency; (ii) the Phonological Similarities effect and Word Length Effect; and (iii) computerised sentence completion and confrontational naming. The tests were designed to control for motor speed and to accommodate for the range of disabilities that are present in ALS patients. Significant impairments were found on some tests of intrinsic response generation, namely the Written Verbal Fluency Test, Category Fluency Test (generation of animal names) and Design Fluency Test. Phonological loop functions appeared to be intact with evidence of both the Phonological Similarities and Word Length Effects, but the ALS patients displayed significantly reduced working memory capacity. No deficits were found on tests of simple word retrieval. The findings indicate that verbal fluency impairments in ALS patients result from a higher order dysfunction, implicating deficits in the supervisory attentional system or central executive component of working memory, and are not caused or exaggerated by an impairment in phonological loop functions or in primary linguistic abilities. The study also demonstrates the importance of controlling for differences in motor speed, which may have served to exaggerate the presence of cognitive deficits in ALS patients reported by some other studies.     

Behavioral markers for self- and other-attribution of memory: a study in patients with temporal lobe epilepsy and healthy volunteers

OBJECTIVES: The correlation between clinical measures of memory and subjectively reported memory is often poor. Regarding this we investigated in patients with temporal lobe epilepsy (TLE) whether there is evidence that persons mistake other cognitive performances for memory due to subjective memory theories. METHODS: a neuropsychological test battery comprising measures of attention, verbal/figural memory and other visual or language related functions was applied in patients with left (L-TLE, n=24) or right temporal lobe epilepsy (R-TLE, n=21) and healthy volunteers (n=20). In addition, subjective self- and other-reported memories were assessed by the subjective memory questionnaire (SMQ). RESULTS: subjective measures as well as objective measures indicate significant cognitive impairment in TLE and in L-TLE in particular. Self-reports and other-reports are interrelated but only self-reported memory correlates significantly with objective memory performance. Regression analysis indicates that self-reported memory is best predicted by word fluency followed by verbal memory and vocabulary, and other-reported memory is best predicted by word fluency, vocabulary, confrontation naming, and verbal recognition memory. DISCUSSION: The results suggest that attribution of memory refers to a subjective view of memory which is wider than its neuropsychological definition. It furthermore differs dependent on the observer's point of view. Memory is preferentially concluded from verbal behaviors. These reflect language skills and access to vocabulary rather than declarative memory. Consideration of subjective memory theories and associated attribution processes can significantly contribute to our understanding of the often-poor relationship between objective test results and subjective impairment in TLE.     

Cognitive impairment in pediatric multiple sclerosis

Cognitive impairment has been recently recognized in patients with pediatric multiple sclerosis in more than 30% of cases. Altered functions with variable frequency are: attention, language (receptive, verbal fluency, naming), visual-spatial and motor functions, spatial memory, executive functions and abstract reasoning. Fatigue and affective disorders are associated, but not correlated with cognitive impairment. The frequency and severity of cognitive impairment increase with time. Cognitive impairment has a negative impact on patient’s life limiting social, academic and recreational activities.     

The therapeutic effect of treatment with RehaCom software on verbal performance in patients with multiple sclerosis

Multiple sclerosis (MS) is characterized by central nervous system lesions that lead to neurological dysfunctions including fatigue, depression and anxiety. MS is affecting almost 2.3 million people around the world, with the significant highest prevalence in the North America. MS also affects different cognitive abilities, such as attention, memory and executive functions. Furthermore, a significant impairment in verbal fluency and naming abilities in patients with MS has been reported. RehaCom, is a software that has improvement effects on cognitive functions. The goal of this research is to investigate the effect of treatment with RehaCom on verbal performance in patients with MS. To select the participants, 60 patients with MS who referred to our clinic were chosen randomly and divided into Control (n = 30) and Experimental (n = 30) groups. The participants in the experimental group were treated by RehaCom software for 10 sessions during 5 weeks (2 sessions per week and each session was 1 h). Controlled Oral Word Association Test (COWAT) and California Verbal Learning Test – Second Edition (CVLT-II), were used to assess verbal performance (verbal fluency, and verbal learning and memory) at weeks 0 (baseline), 5 (post-test) and 10 (follow-up). The results showed that, treatment with RehaCom improved verbal performance in patient with MS, at both post-test and follow-up stages. In conclusion, treatment with RehaCom cognitive rehabilitation software can improve verbal fluency, and verbal learning and memory in patient with MS, possibly by affecting the brain regions involved in language performance.     

Cognition in Friedreich Ataxia

Friedreich ataxia (FRDA) is the most frequent of the inherited ataxias. However, very few studies have examined the cognitive status of patients with genetically defined FRDA. Our aim was to study cognitive performance of FRDA patients taking into account the motor problems characteristic of this clinical population. Thirty-six FRDA patients were administered a comprehensive neuropsychological battery measuring multiple domains: processing speed, attention, working memory, executive functions, verbal and visual memory, visuoperceptive and visuospatial skills, visuoconstructive functions, and language. Thirty-one gender, age, years of education, and estimated IQ-matched healthy participants served as control subjects. All participants were native Spanish speakers. Patients showed decreased motor and mental speed, problems in conceptual thinking, a diminished verbal fluency, deficits in acquisition of verbal information and use of semantic strategies in retrieval, visuoperceptive and visuoconstructive problems, and poor action naming. Scores on the depression inventory were significantly higher in patients than controls, but depression did not account for group differences in cognitive performance. The observed pattern of neuropsychological impairment is indicative of executive problems and parieto-temporal dysfunction. Neuropathological and neuroimaging studies with FRDA patients have reported only mild anomalies in cerebral hemispheres. Thus, cognitive impairment in FRDA is probably caused by the interruption of the cerebro-cerebellar circuits that have been proposed as the anatomical substrate of the cerebellar involvement in cognition.     

Fluency in multiple sclerosis: which measure is best?

Tests of verbal fluency provide brief and sensitive measures of the deficits in rapidly retrieving overlearned information common in multiple sclerosis (MS). Production of words that begin with the letters F, A, and S is the verbal fluency measure most often used with patients who are fluent in English. However, because of frequency of words beginning with certain letters varies from one language to another, it is unlikely that any fixed set of letters will be appropriate for multicenter trials that involve patients who are fluent in different languages. A possible alternative involves using semantic fluency categories that contain such a large number of exemplars that no fluent speaker of any language could exhaust the category in the allotted response time. To examine the potential usefulness of semantic fluency measures, 203 MS patients and 87 healthy controls generated words that begin with F, A, or S or were exemplars of the categories animals and parts of the body. Receiver operating characteristic (ROC) curve analyses indicated that sensitivities and specificities for the three fluency measures in discriminating patients from controls were quite similar, especially if patients with global cognitive impairment were excluded.     

Verbal fluency deficits in multiple sclerosis

A quantitative review of 35 studies with 3673 participants was conducted to estimate and compare the magnitude of deficits upon tests of phonemic and semantic fluency for participants with multiple sclerosis (MS) relative to healthy controls. Participants with MS were substantially but similarly impaired on tests of phonemic and semantic fluency. These deficits were larger than deficits on measures of verbal intelligence, confrontation naming and another widely used measure of executive functioning, the Wisconsin Card Sorting Test, but were of a comparable or smaller magnitude relative to deficits on the oral version of the Symbol Digit Modalities Test (SDMT). This is consistent with other research suggesting that measures of verbal fluency and the SDMT may be amongst the most sensitive neuropsychological measures to cognitive impairment in MS. Increased neurological disability and a chronic progressive (as opposed to a relapsing remitting) disease course were associated with larger deficits on tests of phonemic and semantic fluency. However, it is suggested that this latter finding is attributable to the distinct clinical features of chronic progressive and relapsing remitting sub-types. Thus, patients who follow a chronic progressive course tend to be older, have an increased duration of illness and experience greater neurological disability. Once these variables were controlled for, differences between the two sub-types were substantially attenuated.     

Brain dysconnectivity relates to disability and cognitive impairment in multiple sclerosis

The pathophysiology of cognitive dysfunction in multiple sclerosis (MS) is still unclear. This magnetoencephalography (MEG) study investigates the impact of MS on brain resting‐state functional connectivity (rsFC) and its relationship to disability and cognitive impairment. We investigated rsFC based on power envelope correlation within and between different frequency bands, in a large cohort of participants consisting of 99 MS patients and 47 healthy subjects. Correlations were investigated between rsFC and outcomes on disability, disease duration and 7 neuropsychological scores within each group, while stringently correcting for multiple comparisons and possible confounding factors. Specific dysconnections correlating with MS‐induced physical disability and disease duration were found within the sensorimotor and language networks, respectively. Global network‐level reductions in within‐ and cross‐network rsFC were observed in the default‐mode network. Healthy subjects and patients significantly differed in their scores on cognitive fatigue and verbal fluency. Healthy subjects and patients showed different correlation patterns between rsFC and cognitive fatigue or verbal fluency, both of which involved a shift in patients from the posterior default‐mode network to the language network. Introducing electrophysiological rsFC in a regression model of verbal fluency and cognitive fatigue in MS patients significantly increased the explained variance compared to a regression limited to structural MRI markers (relative thalamic volume and lesion load). This MEG study demonstrates that MS induces distinct changes in the resting‐state functional brain architecture that relate to disability, disease duration and specific cognitive functioning alterations. It highlights the potential value of electrophysiological intrinsic rsFC for monitoring the cognitive impairment in patients with MS.     

Neocortical volume decrease in relapsing-remitting multiple sclerosis with mild cognitive impairment

The aim of the study was to assess neocortical changes and their relevance to cognitive impairment in early relapsing-remitting multiple sclerosis (RRMS). Conventional magnetic resonance was acquired in 41 RRMS patients and 16 demographically matched normal controls (NC). An automated analysis tool was used to obtain measures of cortical brain volumes normalized for head size. Neuropsychological performance of MS patients was assessed through the Rao's Brief Repeatable Battery. We identified 18 cognitively preserved (MS-cp) and 23 cognitively impaired (MS-ci) MS patients. Values of normalized cortical volumes (NCV) in the whole MS sample were lower than those in the NC group (p=0.01). MS-ci patients showed NCV values lower (p=0.02) than did both MS-cp patients and NC. Moreover, we found a positive correlation between NCV values and measures of verbal memory (r=0.51, p=0.02), verbal fluency (r=0.51, p=0.01) and attention/concentration (r=0.65, p<0.001) in MS-ci patients. Furthermore, NCV values were significantly decreased in patients who scored lower on a greater number of tests (r=-0.58, p<0.01) in the MS-ci group. Only MS-ci patients had cortical atrophy significantly correlated with a poorer neuropsychological performance. Grey matter pathology may contribute to the development of cognitive impairment in MS from the earliest stages of the disease.     

Neocortical atrophy, third ventricular width, and cognitive dysfunction in multiple sclerosis

BACKGROUND: Cognitive dysfunction is common in multiple sclerosis (MS). Correlations are reported between atrophy and neuropsychological test results. OBJECTIVE: To determine if neocortical volume would supplant or supplement third ventricular width and other magnetic resonance imaging measures when predicting neuropsychological impairment. DESIGN: Cross-sectional study. SETTING: University MS clinic. PARTICIPANTS: Seventy-seven patients with relapsing-remitting MS, 42 patients with secondary progressive MS, and 27 healthy control subjects. MAIN OUTCOME MEASURES: Brain atrophy and lesion burden measures were obtained in all patients. A subset of 82 patients and all controls underwent neuropsychological testing. RESULTS: Patients with secondary progressive MS had more atrophy than patients with relapsing-remitting MS and controls. Neocortical volume was significantly correlated with all neuropsychological measures, with r values ranging from 0.29 to 0.58. Third ventricular width was retained in most stepwise regression analyses predicting cognitive impairment in patients with MS and distinguishing secondary progressive from relapsing-remitting courses of MS. CONCLUSIONS: We confirm an association between neocortical volume and multiple cognitive domains in MS, although neocortical volume did not explain significantly more variance than other magnetic resonance imaging measures. Of the magnetic resonance imaging variables studied, third ventricular width was retained in most regression models.     

Anterior corpus callosum atrophy and verbal fluency in multiple sclerosis.

To determine whether different portions of the corpus callosum (CC) are responsible for transferring the information of specific cognitive modalities, eighteen females with relapsing-remitting Multiple Sclerosis (MS) were studied using neuropsychological procedures and Magnetic Resonance Imaging (MRI). Measures of both anterior and posterior CC areas were obtained in patients with MS as well as in eighteen age and sex matched healthy controls. MRI scans were additionally analyzed for each patient in order to evaluate the extent of demyelinating lesions in both periventricular and subcortical areas. Patients with MS exhibited a significant decrease in both the anterior and posterior CC areas compared with normal subjects. The results of statistical analysis showed that, even when the effect of demyelinating lesions was taken into account within a regression equation, the atrophy of anterior CC area strongly affected the performance on verbal fluency task. These data emphasize the importance of the anterior CC area for the interhemispheric transfer of cognitive information associated with verbal fluency.     

Role of cognitive control in language deficits in different types of aphasia

ABSTRACT

Background: Although studies show that different facets of cognitive control are impaired in persons with aphasia (PWA), the question how they impact language abilities in different types of aphasia remains open.

Aims: Following the hypothesis that diminished attention contributes to language impairments in aphasia, we predicted that both fluent and non-fluent PWA would perform worse than neurologically intact individuals on verbal and non-verbal cognitive control tasks. Also, testing the view that linguistic disturbances in fluent and non-fluent PWA dissociate, we predicted differential relationships in performance on cognitive control tasks and language impairment.

Methods & Procedures: Fluent PWA (N = 17) and non-fluent PWA (N = 14) were compared to unimpaired speakers (N = 21) on the non-verbal Flanker task tapping domain-general cognitive control, and Stroop task measuring verbal cognitive control, as well as subtests from the Russian version of the Birmingham Cognitive Screen, namely the Auditory Control task tapping verbal cognitive control and the Rule Finding task measuring domain-general cognitive control. All PWA completed picture naming and language comprehension tasks.

Outcomes & Results: All PWA were more impaired on the Stroop and Auditory Control tasks, with no impairment on the non-verbal Flanker task compared to the controls. Non-fluent PWA also performed significantly worse on the Rule Finding that requires forming and updating non-verbal relational representations. Differences between aphasia groups were found on the Auditory Control task only, where non-fluent PWA were more vulnerable to task demands. Correlation analyses found that verbal and non-verbal cognitive control performance was correlated for the non-fluent group, whereas only correlations between verbal cognitive control tasks were significant for the fluent group. For all PWA, non-verbal cognitive control indexed by Flanker interference scores was related to language comprehension, whereas verbal cognitive control was related to picture naming. However, non-verbal relational reasoning as indexed by the Rule Finding task was significantly related to language comprehension in the non-fluent group only.

Conclusions: All PWA had diminished verbal cognitive control. Non-fluent PWA demonstrated higher vulnerability to domain-general cognitive control deficits compared to fluent PWA. Performance on verbal and non-verbal cognitive control tasks significantly overlapped in the non-fluent group only. Both groups recruited non-verbal cognitive control during language comprehension and verbal cognitive control during picture naming. Only non-fluent PWA relied on domain-general relational reasoning during language comprehension. These findings reinforce the importance of cognitive assessment in aphasia.     

Cognitive impairment in Parkinson's disease without dementia

Some degree of cognitive impairment appears frequently in Parkinson's disease (PD) patients, even at the onset of the disease. However, due to the heterogeneity of the patients and the lack of standardized assessment batteries, it remains unclear which capacities are primarily affected by this disease. Fifty PD patients were assessed with 15 tests including executive functions, attention, temporal and spatial orientation, memory, and language tasks. Their results were compared with those of 42 age‐ and education‐matched healthy seniors. Semantic fluency, along with visual search appeared to be the most discriminant tasks, followed by temporal orientation and face naming, as well as action naming and immediate recall. PD patients studied showed an impairment of frontal‐ to posterior‐dependent capacities. Executive functions, attention, and recall tasks appeared to be significantly impaired in the patients. Nevertheless, significantly poor scores in tasks like action and face naming, as well as semantic fluency, also reveal a mainly semantic deficit. © 2010 Movement Disorder Society     

Cognitive impairment in primary and secondary progressive multiple sclerosis

The aim of this study was to use neuropsychological data to characterize two subtypes of multiple sclerosis (MS) patients in a large patient sample. We studied patients with primary-progressive MS (PPMS) and secondary-progressive MS (SPMS). A group of 121 MS patients (36 PPS, 85 SPMS) and 40 healthy controls were administered a brief battery of cognitive tests. Executive functioning, memory and attention were studied. Results demonstrate that PPMS patients exhibited slightly more impairment than patients with SPMS, although this difference is not significant (50% vs 37%). However, PPMS patients revealed a significantly poorer performance in verbal learning (p < 0.05) and in verbal fluency (p < 0.05). Whereas PPMS patients had significantly shorter disease durations (p < 0.05), there was no statistical difference in disability between both groups. We conclude from our study that cognitive deficits in progressive MS are frequent. Patients with PPMS tend to be more frequently and severely affected than SPMS patients. Our findings of high prevalence of cognitive involvement in PPMS have not been reported previously