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International audience; In contrast to short-term cognitive outcomes, long-term cognitive outcomes (over 5 years) has been scarcely assessed so far. Yet, predicting long-term outcomes at any time point of the epilepsy, from initial diagnosis, to medically intractability is very important for therapeutic decision-making, patient information, and orientation. Assessing long-term cognitive outcomes in patients with epilepsy would ideally require longitudinal studies and a comparison with a healthy controls group. This issue has been addressed extensively, but with controversial results. However, there is a general consensus about the fact that cognitive outcome is not the same in all groups of patients with epilepsy. Possible prognostic factors include age at onset, duration of epilepsy, syndrome and etiology, seizure outcome and therapeutics. The multiplicity of factors makes it very difficult to assess their relative weight in individuals. Although long-term cognitive outcome studies are scarce, this issue has been specifically studied in newly diagnosed epilepsies and in focal drug-resistant epilepsies. In the first clinical setting, i.e. newly diagnosed epilepsy, it appears that cognitive deficits are already present at epilepsy onset in a significant proportion of patients but seem to remain stable over time. In focal drug-resistant epilepsies, cognitive deficits (mainly verbal memory) were generally shown to remain stable provided that seizures were controlled either by medication or by surgery. Beyond the possible correlation between seizure and cognitive outcome, no causal link however has been demonstrated between these two important outcomes.

Previous researches have shown that the inferior frontal gyrus (IFG) is involved in time and numerosity processing. This study aimed at examining (i) interval timing and (ii) interaction between duration and numerosity processing in four drug-resistant epileptic patients with postoperative lesions in the IFG in comparison with thirteen healthy controls. The duration reproduction and discrimination tasks performed in the sub- and supra-second ranges did not reveal any significant differences between patients and controls. The duration discrimination task of stimuli varying in numerosity (DurN) and the numerosity discrimination task of stimuli varying in duration (NumD) revealed that only numerosity judgment was altered in IFG patients. A time-order effect was notably observed in the NumD task but in opposite directions for the two groups: The second patch was perceived as more numerous than the first patch in controls and conversely as less numerous in patients. Finally in the DurN task, we observed a congruency effect which was dependent on numerical distance in patients but not in controls. These converging results suggest that the IFG would be more specifically involved in numerosity than in duration processing, possibly playing a role in numerical decision.

International audience; Patients with chronic mesial temporal lobe epilepsy have difficulties at identifying familiar faces as well as at explicit old/new face recognition tasks. However, the extent to which these difficulties can be attributed to visual individuation of faces, independently of general explicit learning and semantic memory processes, is unknown. We tested 42 mesial temporal lobe epilepsy patients divided into two groups according to the side of epilepsy (left and right) and 42 matched controls on an extensive series of individuation tasks of unfamiliar faces and control visual stimuli, as well as on face detection, famous face recognition and naming, and face and non-face learning. Overall, both patient groups had difficulties at identifying and naming famous faces, and at explicitly learning face and non-face images. However, there was no group difference in accuracy between patients and controls at the two most widely used neuropsychological tests assessing visual individuation of unfamiliar faces (Benton Facial Recognition Test and Cambridge Face Memory Test). While patients with right mesial temporal lobe epilepsy were slowed down at all tasks, this effect was not specific to faces or even high-level stimuli. Importantly, both groups showed the same profile of response as typical participants across various stimulus manipulations, showing no evidence of qualitative processing impairments. Overall, these results point to largely preserved visual face individuation processes in patients with mesial temporal lobe epilepsy, with semantic and episodic memory difficulties being consistent with the localization of the neural structures involved in their epilepsy (anterior temporal cortex and hippocampus). These observations have implications for the prediction of neuropsychological outcomes in the case of surgery and support the validity of intracranial electroencephalographic recordings performed in this population to understand neural mechanisms of human face individuation, notably through intracranial electrophysiological recordings and stimulations.

OBJECTIVEIn drug-resistant temporal lobe epilepsy (TLE) patients, the authors evaluated early and late outcomes for decline in visual object naming after dominant temporal lobe resection (TLR) according to the resection status of the basal temporal language area (BTLA) identified by cortical stimulation during stereoelectroencephalography (SEEG).METHODSTwenty patients who underwent SEEG for drug-resistant TLE met the inclusion criteria. During language mapping, a site was considered positive when stimulation of two contiguous contacts elicited at least one naming impairment during two remote sessions. After TLR ipsilateral to their BTLA, patients were classified as BTLA+ when at least one positive language site was resected and as BTLA− when all positive language sites were preserved. Outcomes in naming and verbal fluency tests were assessed using pre- and postoperative (means of 7 and 25 months after surgery) scores at the group level and reliable change indices (RCIs) for clinically meaningful changes at the individual level.RESULTSBTLA+ patients (n = 7) had significantly worse naming scores than BTLA− patients (n = 13) within 1 year after surgery but not at the long-term evaluation. No difference in verbal fluency tests was observed. When RCIs were used, 5 of 18 patients (28%) had naming decline within 1 year postoperatively (corresponding to 57% of BTLA+ and 9% of BTLA− patients). A significant correlation was found between BTLA resection and naming decline.CONCLUSIONSBTLA resection is associated with a specific and early naming decline. Even if this decline is transient, naming scores in BTLA+ patients tend to remain lower compared to their baseline. SEEG mapping helps to predict postoperative language outcome after dominant TLR.

Objective: The aim of this study is to determine the effectiveness of an extended cognitive rehabilitation program in group’s sessions in multiple sclerosis. Design: Double-blind multicenter randomized trial. Participants: People with multiple sclerosis of 18 to 60 years, Expanded Disability Status Scale ⩽6.0, mild to moderate cognitive impairment. Interventions: They were randomized into cognitive rehabilitation program (ProCog-SEP) or in a placebo program. ProCog-SEP comprises 13 group’s sessions over 6 months and includes psychoeducational advices and cognitive exercises. Placebo program included non-cognitive exercises. No strategy and no cognitive advice were provided. Main measures: The primary endpoint was the percentage of verbal memory learning measured by the Selective Reminding Test. A comprehensive neuropsychological assessment is carried out before and after interventions by a neuropsychologist blinded to intervention. Effectiveness of the ProCog-SEP versus Placebo has been verified using linear regression models. Results: In total, 128 participants were randomized and 110 were included in the study after planning session in groups; 101 completed this trial (77.2% females); mean age: 46.1 years (±9.6); disease duration: 11.8 years (±7.5). ProCog-SEP was more effective in increasing in learning index (9.21 (95% confidence interval (CI): 1.43, 16.99); p = 0.02) and in working memory on manipulation (0.63 (95% CI: 0.17, 1.09); p = 0.01), and updating capacities (–1.1 (95% CI: –2.13, –0.06); p = 0.04). No difference was observed for other neuropsychological outcomes. Regarding quality of life outcomes, no change was observed between the two groups. Conclusion: These findings suggest that ProCog-SEP could improve verbal learning abilities and working memory in people with multiple sclerosis. These improvements were observed with 13 group sessions over 6 months.

International audience; Highlights• Cognitive impairment in multiple sclerosis could be reduce with cognitive rehabilitation, in particular in verbal memory.• Metacognition is a key point of cognitive rehabilitation, with cognitive exercises adapted to a neuropsychological profile.• Clinical rehabilitation software is effective and available in different languages. It should be administered by a therapist.• More studies are needed to develop clinical tools in order to adapt individual neuropsychological care.

Introduction Surgical resection in premotor areas can lead to supplementary motor area syndrome as well as a permanent deficit. However, recent findings suggest a putative role of the negative motor network in those dysfunctions. Our objective was to compare the functional results in two groups of adult patients who underwent the resection of a frontal glioma with and without resection of the negative motor networks. Material and methods Twelve patients (total of 13 surgeries) were selected for awake surgery for a frontal glioma. Negative motor responses were monitored during surgery at the cortical and subcortical levels. Sites eliciting negative motor responses were first identified then spared (n = 8) or removed (n = 5) upon oncological requirements. Results In the group with removal of the negative motor network (n = 5), all patients presented a complete supplementary motor area syndrome with akinesia and mutism. At 3 months, they all presented bimanual coordination dysfunction and fine movement disorders. In the group with preservation of the negative motor network (n = 8), all patients presented transient and slight disorders of speech or upper limb, they all recovered completely at 3 months. Discussion The negative motor network is a part of a modulatory motor network involved in the occurrence of the supplementary motor area syndrome and the permanent deficit after resection in premotor areas. Then, intraoperative functional cortico-subcortical mapping using direct electrostimulation under awake surgery seems mandatory to avoid deficit in bimanual coordination and fine movements during surgery in premotor areas.

International audience; Rapid individuation of conspecifics' faces is ecologically important in the human species, whether the face belongs to a familiar or unfamiliar individual. Here we tested a large group (N = 69) of epileptic patients implanted with intracerebral electrodes throughout the ventral occipito-temporal cortex (VOTC). We used a frequency-tagging visual stimulation paradigm optimized to objectively measure face individuation with direct neural recordings. This enabled providing an extensive map of the significantly larger neural responses to upright than to inverted unfamiliar faces, i.e. reflecting visual face individuation processes that go beyond physical image differences. These high-level face individuation responses are both distributed and anatomically confined to a strip of cortex running from the inferior occipital gyrus all along the lateral fusiform gyrus, with a large right hemispheric dominance. Importantly, face individuation responses are limited anteriorly to the bilateral anterior fusiform gyrus and surrounding sulci, with a near absence of significant responses in the extensively sampled temporal pole. This large-scale mapping provides original evidence that face individuation is supported by a distributed yet anatomically constrained population of neurons in the human VOTC, and highlights the importance of probing this function with face stimuli devoid of associated semantic, verbal and affective information.

International audience; Introduction: Neuropsychological assessment is an integral component of the surgical procedure in patients with epilepsy. As no French consensus for neuropsychological assessment was available, the main goal of this work was to define French neuropsychological procedure consensus in regard to literature review.Method: A panel of expert in neuropsychology was created within the framework of the French League Against Epilepsy. A systematic search of publications from 1950 to 2017 listed in PubMed database was conducted leading to a classification of articles according to their level of scientific evidence. French neuropsychological procedure consensus was then carried out with an expert panel of expert.Results: Low scientific evidence of neuropsychological data was reported. A panel of expert proposed a comprehensive neuropsychological assessment procedure including the exploration of intellectual efficiency, long-term memory, short-term and working memory, attention, executive functions, processing speed and motor skills, language, visual processing, praxis, psychobehavioral, and social cognition.Discussion: A common procedure for assessing cognitive and psychobehavioral function is now available in patients with epilepsy undergoing surgical evaluation have been established, they may help to improve the quality of care and the patient experience. This work highlights the need of furthers investigations and the necessity to develop specific tools with normative data.

International audience; While cognition and depression have often been studied in patients with epilepsy, only a few studies have so far attempted to link these two domains, and more specifically to investigate the specific impact of depression on cognition in epilepsy. In this review, we performed an extensive search of the literature database to provide a better understanding of this subject. Using several inclusion criteria (adult population, quantitative depression/neuropsychological assessment, statistical analyses of the impact of depression on cognitive scores, patients with epilepsy (PWE) and no other neurological disease, and studies including at least 20 patients), we identified 20 articles (out of 712 search results) that investigated both depression and cognition in PWE. Their results were summarized using a narrative and descriptive approach. This review highlights a variable impact of depression on cognition in PWE, depending on the laterality of the seizure onset zone, the type of epilepsy and the surgical context. We emphasize the need for a systematic depression assessment in these patients, especially since depressed PWE will benefit from prompt and appropriate care to help them avoid cognitive decline, particularly in a surgical context.

International audience; Compared to patients with prosopagnosia, other animal species, infants or children, neurotypical human adults are experts at individuating pictures of unfamiliar faces, but the neural basis of this function remains largely unknown. Since an increasing number of studies rely on intracranial recordings in anterior temporal epileptic patients (aTLE) to investigate the neural mechanisms of face recognition, it is important to assess aTLE patients’ ability to discriminate and match unfamiliar individual faces. Here, we tested 42 patients with left (n=17) or right (n=25) aTLE, and 42 healthy matched controls. Seven computerized neuropsychological tests were administered: the Benton Face Recognition Test (BFRT), the Cambridge Face Memory Test (CFMT), delayed matching of upright pictures of faces and objects, the Mooney Face Test, famous face recognition and naming, unfamiliar face and object learning. Relative to controls, we found that (1) both left and right aTLE patients were impaired (−10.5% and −8.2% in accuracy, respectively) in learning unfamiliar faces, but without any specificity (i.e. impairment also for nonface objects); (2) on average, right aTLE patients had significantly slower response times at all tasks, but this included the WAIS’ Code subtest assessing processing speed, showing that this effect is not specific to visual tasks and (3) importantly, there was no difference between aTLE patients and matched controls on all the tasks assessing individual face discrimination (mean BFRT scores at 42.3/54 and 42.6/54 and CFMT scores at 47.2/72 and 47.1/72 for left and right aTLE respectively, significant inversion effect for matching individual faces but not cars). Overall, our study shows that left and right aTLE patients do not differ quantitatively and qualitatively at unfamiliar face discrimination tasks relative to healthy controls.

International audience; Human face perception requires a network of brain regions distributed throughout the occipital and temporal lobes with a right hemisphere advantage. Present theories consider this network as either a processing hierarchy beginning with the inferior occipital gyrus (occipital face area; IOG-faces/OFA) or a multiple-route network with nonhierarchical components. The former predicts that removing IOG-faces/OFA will detrimentally affect downstream stages, whereas the latter does not. We tested this prediction in a human patient (Patient S.P.) requiring removal of the right inferior occipital cortex, including IOG-faces/OFA. We acquired multiple fMRI measurements in Patient S.P. before and after a preplanned surgery and multiple measurements in typical controls, enabling both within-subject/across-session comparisons (Patient S.P. before resection vs Patient S.P. after resection) and between-subject/across-session comparisons (Patient S.P. vs controls). We found that the spatial topology and selectivity of downstream ipsilateral face-selective regions were stable 1 and 8 month(s) after surgery. Additionally, the reliability of distributed patterns of face selectivity in Patient S.P. before versus after resection was not different from across-session reliability in controls. Nevertheless, postoperatively, representations of visual space were typical in dorsal face-selective regions but atypical in ventral face-selective regions and V1 of the resected hemisphere. Diffusion weighted imaging in Patient S.P. and controls identifies white matter tracts connecting retinotopic areas to downstream face-selective regions, which may contribute to the stable and plastic features of the face network in Patient S.P. after surgery. Together, our results support a multiple-route network of face processing with nonhierarchical components and shed light on stable and plastic features of high-level visual cortex following focal brain damage.SIGNIFICANCE STATEMENT Brain networks consist of interconnected functional regions commonly organized in processing hierarchies. Prevailing theories predict that damage to the input of the hierarchy will detrimentally affect later stages. We tested this prediction with multiple brain measurements in a rare human patient requiring surgical removal of the putative input to a network processing faces. Surprisingly, the spatial topology and selectivity of downstream face-selective regions are stable after surgery. Nevertheless, representations of visual space were typical in dorsal face-selective regions but atypical in ventral face-selective regions and V1. White matter connections from outside the face network may support these stable and plastic features. As processing hierarchies are ubiquitous in biological and nonbiological systems, our results have pervasive implications for understanding the construction of resilient networks.

Introduction Chez l’enfant avec epilepsie partielle pharmaco-resistante, la chirurgie est une option therapeutique recommandee pour le traitement des crises. Les donnees concernant l’impact cognitif de la chirurgie sont moins consensuelles. Objectifs A l’initiative de la Ligue francaise contre l’epilepsie, un groupe de travail d’experts en neuropsychologie (EPI-NEUROPSY) a etabli des recommandations francophones a l’evaluation neuropsychologique dans le contexte chirurgical. Patients et methodes Une revue systematique de la litterature a ete realisee des annees 1950 a 2017 (Pubmed). Les articles ont ete analyses a partir d’une grille de lecture clinique, neuropsychologique et methodologique. Une classification des articles selon leur niveau de preuve scientifique (niveau 1 (evidence forte)–4 (faible)) a partir des criteres de la H.A.S. a ete realisee. Enfin, un argumentaire et une liste de recommandations ont ete elabores par consensus d’experts. Resultats Sur 1920 abstracts initialement identifies sur PubMed, 613 articles ont ete selectionnes. Apres analyse complete, seuls 45 articles concernaient la chirurgie de l’epilepsie de l’enfant ; leur niveau de preuve etait les suivants : niveau 1 (0 %), niveau 2 (6,6 %), niveau 3 (8,8 %) et niveau 4 (84,4 %). Le groupe d’expert a requis d’explorer systematiquement 8 dimensions cognitives. Des epreuves ont ete selectionnees et des preconisations sur les periodes d’evaluation ont ete elaborees. Discussion Ces resultats montrent le peu de donnees neuropsychologiques publiees dans le contexte de la chirurgie de l’epilepsie de l’enfant. De nombreuses publications ont ete exclues du fait de faible effectif, de l’absence de population controle ou de suivi prospectif et de l’heterogeneite des populations. Dans ce contexte, les recommandations francaises pour cette population specifique ont ete etablies par consensus d’experts. Conclusion Les premieres recommandations francaises concernant l’evaluation neuropsychologique perichirurgicale de l’epilepsie sont etablies pour les enfants pour permettre des etudes collaboratives. Elles pourront egalement ameliorer la qualite des prises en charge.

Le devenir cognitif des patients adultes apres chirurgie des epilepsies focales structurelles pharmaco-resistantes est un enjeu majeur de la prise en charge et participe de facon determinante a leur qualite de vie. Les resultats des etudes menees sur le sujet sont tres importants a connaitre a la fois en terme de prevalence et de facteurs predictifs afin de pouvoir bien informer les patients, de predire individuellement leur devenir, de les accompagner eventuellement par des mesures de remediation cognitive pre ou postoperatoire. C’est egalement un element determinant dans la prise de decision chirurgicale qui repose sur la mise en perspective des risques et des benefices de la chirurgie. Longtemps, le devenir cognitif postoperatoire a ete envisage uniquement sous l’angle du seul risque de deficit cognitif postoperatoire en particulier sur la memoire episodique verbale et l’acces lexical dans la chirurgie du lobe temporal. En effet, les etudes de devenir cognitif a court terme montrent un risque significatif de deficit en memoire verbale et en acces lexical predit par la lateralite gauche de la chirurgie, l’âge, la presence ou non d’une lesion structurelle hippocampique, le succes de la chirurgie sur les crises. Toutefois les etudes a plus long terme qui sont plus rares demontrent l’existence d’un profil evolutif plus complexe et nuance avec l’existence possible d’amelioration cognitive dans certains domaines, de recuperation a long terme du deficit postoperatoire precoce lorsqu’il est present, soulignant l’importance d’explorer d’autres domaines cognitifs que la memoire, telles que les fonctions attentionnelles, la memoire a court terme, les fonctions executives. Le devenir cognitif tout comme la qualite de vie en postoperatoire sont egalement tres lies a la presence eventuelle de co-morbidites psychiatriques et a leur prise en charge adequate.

International audience; Cognitive consequences in epilepsy are often described in the following domains: verbal memory, language, executive functions, and attention. Attention is involved in all cognitive activities, and attention disorders (AD) are reported in patients with various neurological diseases. This paper proposes to define the concept of AD and its assessment, to consider their determinants in epilepsy and potential therapies (drug or not). ADs are reported in new onset epilepsy, generalized epilepsy of presumed genetic origin, and in focal epilepsy. In focal epilepsy, alertness and divided attention impairment are observed and seem to improve after successful curative surgery. Additional studies are needed to assess the prevalence and nature of AD related to status epilepticus. In the field of therapeutic strategies, anti-epileptic drugs show an impact on AD. Effects of antidepressive drug therapy are not reported, as well as psychotherapy. Cognitive rehabilitation on AD is a promising therapeutic intervention but specific studies are needed to assess its efficacy.

We report the case of a patient (MB, young female human subject) who systematically experiences confusion between perceived facial identities when electrically stimulated inside the lateral section of the right fusiform gyrus. In the presence of a face stimulus (an experimenter or a photograph), intracerebral electrical stimulation in this region generates a perceptual hallucination of an individual facial part integrated within the whole perceived face, i.e. facial palinopsia. In the presence of a distracting stimulus (visual scene or object picture), the patient also experiences an individual face percept superimposed on the non-face stimulus. The stimulation site evoking this category-selective transient palinopsia is localized in a region showing highly selective responses to faces both with functional magnetic resonance imaging (“Fusiform Face Area”, “FFA”) and intracerebral electrophysiological recordings during fast periodic visual stimulation (FPVS). Importantly, the largest electrophysiological response to fast periodic changes of facial identity is also found at this location. Altogether, these observations suggest that a local face-selective region of the right lateral fusiform gyrus suffices to generate a vivid percept of an individual face, supporting the active role of this region in individual face representation.

Resume Introduction Les troubles cognitifs sont frequents dans les epilepsies pharmacoresistantes. Leur evaluation dans le contexte chirurgical apparait indispensable. Dans l’objectif d’une harmonisation des pratiques, un recensement francais a ete effectue. Objectifs A l’initiative de la ligue francaise contre l’epilepsie, un recensement des pratiques et outils specifiques au bilan neuropsychologique a ete realise aupres des centres experts pratiquant la chirurgie de l’epilepsie. Patients et Methodes Un questionnaire detaille a ete envoye a seize centres. Il interrogeait la duree du bilan neuropsychologique dans le contexte chirurgical, les differents acteurs impliques dans la prise en charge et l’ensemble des epreuves utilisees au sein de chaque dimension cognitive. Quinze centres ont participe au recensement. Resultats La duree moyenne du bilan neuropsychologique est de 3h30. Un consensus fort a ete mis en evidence pour l’efficience intellectuelle (WAIS) ; un consensus eleve pour les fonctions executives (TMT, Stroop, Empans de chiffres, WCST, fluences verbales) et pour le langage. Toutefois, l’evaluation mnesique recense vingt epreuves differentes. L’evaluation des capacites visuo-spatiales n’est pas consensuelle et peu de centres evaluent les fonctions praxiques et motrices. Enfin, l’evaluation thymique retrouve un consensus avec l’inventaire de Beck. Discussion Le recensement francais presente des similarites avec les observations d’autres pays pratiquant la chirurgie de l’epilepsie. Il n’existe pas de bilan type avec des outils specifiques, utilises par tous, mais des consensus sont soulignes. Actuellement avec le developpement des projets de recherche cliniques nationaux et europeens, les cliniciens et chercheurs se concertent autour des possibilites de recommandations d’epreuves neuropsychologiques. Conclusion Cette premiere etape, indispensable a l’elaboration des premieres recommandations francaises, a permis la constitution d’un groupe de travail visant l’amelioration des pratiques neuropsychologiques autour de la chirurgie de l’epilepsie.

Cognitive impairments are frequent in multiple sclerosis (MS). However, most studies about efficacy of cognitive rehabilitation interventions have been criticized in terms of methods and/or design. The aim of this study is to evaluate the efficacy of cognitive rehabilitation in MS patients with a cognitive intervention (ProCogSEP* program), compared to a control intervention (discussion program). Twenty MS patients have completed this simple blind study: 10 patients followed 13 sessions (2 hours) of the ProCog-SEP(1) program. Ten other patients followed 13 sessions (2 hours) of a discussion program (Control Group). All patients underwent neuropsychological assessment, before and after their program, in order to evaluate cognitive functions. Two neuropsychologists respectively assessed the patients and conducted the group sessions. Compared to its own baseline, ProCog-SEP Group show improvements in verbal memory [free recall (p = .02), learning (p = .002)], in visual memory [free (p = .05) and delayed recall (p = .007)], in working-memory (p = .03), in verbal fluency (p = .05) and in language (p = .01). Inter group analysis show a benefit of cognitive program mainly in verbal and visual memory, and in verbal fluencies. These results support the interest of a cognitive therapeutic management of MS patients.

International audience; While object naming is traditionally considered asa left hemisphere function, neuroimaging studies have reported activations related to naming in the ventral temporal cortex (VTC) bilaterally. Our aim was to use intracerebral electrical stimulation to specifically compare left and right VTC in naming. In twenty-three epileptic patients tested for visual object naming during stimulation, the proportion of naming impairments was significantly higher in the left than in the right VTC (31.3% vs 13.6%). The highest proportions of positive naming sites were found in the left fusiform gyrus and occipito-temporal sulcus (47.5% and 31.8%). For 17 positive left naming sites, an additional semantic picture matching was carried out, always successfully performed. Our results showed the enhanced role of the left compared to the right VTC in naming and suggest that it may be involved in lexical retrieval rather than in semantic processing.

Resume Introduction Les troubles de la memoire de travail (MDT) chez les patients atteints de sclerose en plaques (SEP) sont frequemment rapportes dans la litterature. Toutefois, les differentes methodologies, ainsi que les populations selectionnees rendent l’interpretation des resultats difficile. L’objectif de ce travail est de proposer une revue d’articles attaches a la memoire de travail (MDT) dans la SEP. Methode Vingt etudes ont ete recensees pour la partie attachee a l’evaluation neuropsychologique de la MDT. Resultats Les etudes s’accordent toutes pour mettre en evidence des troubles en MDT chez les patients SEP. La vitesse de traitement serait une atteinte centrale chez ces patients et aurait des repercussions sur les performances en MDT. Concernant le modele de MDT de Baddeley, les deficits se situeraient davantage au niveau de l’administrateur central. Les patients SEP seraient sensibles aux tâches avec une charge cognitive elevee, toutefois lorsque l’on adapte la vitesse, les performances seraient meilleures. Les travaux d’imagerie ont propose differents modeles d’explication relatifs a ces troubles. La compensation pourrait masquer les deficits en MDT a un stade precoce de la maladie, mais s’estomperait avec la duree de maladie et la charge requise avec la tâche. Conclusions/perspectives Afin de mesurer la MDT, des outils adaptes prenant en compte la vitesse de traitement devraient etre proposes aux patients SEP. Par ailleurs, une dissociation des processus au sein de l’administrateur central, relativement au modele de Miyake n’a pas ete etudiee. De plus, les travaux d’imagerie rapportent des resultats essentiels pour la comprehension des mecanismes de compensation et pourraient permettre d’envisager des pistes pour des prises en charge adaptees a ces troubles invalidants au quotidien.

Resume Introduction Bien que les troubles cognitifs dans la sclerose en plaques soient bien etablis, meme au debut de la maladie, aucune prise en charge n’est pour autant proposee. L’objectif de cette etude etait d’elaborer et d’evaluer l’efficacite d’un programme de remediation cognitive (PROCOG-SEP) en proposant divers exercices se referant aux theories actuelles de remediation dont le principe se base sur la stimulation des fonctions preservees. Methode Le programme PROCOG-SEP est base sur le principe des techniques de facilitation. Vingt-quatre patients presentant une SEP peu invalidante (Expanded Disability Status Scale [EDSS] Resultats Une amelioration des capacites en memoire episodique verbale et memoire episodique visuelle, d’autogeneration et de flexibilite motrice a ete mise en evidence. En revanche, ce programme n’a pas permis de montrer une amelioration des capacites d’attention soutenue (PASAT), de la memoire de travail verbale et de la vitesse de traitement. Conclusion La remediation cognitive pourrait ameliorer le fonctionnement quotidien dans la SEP et diminuer le cout global de la maladie pour la societe.

Background: Estimates of the prevalence of cognitive impairment among patients with multiple sclerosis (MS) range between 40 and 70%. The current cerebral functional system (CFS) of the Expanded Disability Status Scale (EDSS) is subjective. Aim: To define a new cerebral functional system (NCFS) based on neuropsychological evaluation (NE). Methods: We prospectively included 215 MS patients. NE evaluated cognitive functions. Fatigue was assessed with the Fatigue Impact Scale. The NCFS was devised with grades from 0 to 5, excluding depression but including fatigue. Grade 1 of the NCFS was integrated in the EDSS as other functional scores. The NCFS and new EDSS including the NCFS were compared with the current CFS and EDSS. Results: 215 patients (69% women, 67% with relapsing-remitting MS, median EDSS 3.0) were assessed. 98% of these patients presented fatigue and/or cognitive impairment with the NCFS compared to 62% with the CFS. The NCFS was higher than the CFS, and the EDSS had changed in 31% of the 113 patients with an EDSS Conclusions: We propose a new CFS grading based on NE, including fatigue, and integrating grade 1 at EDSS.

To determine the value of fatigue in predicting the change in disability status in patients with multiple sclerosis (MS), we realized a prospective population-based cohort study of 196 patients with clinically definite MS. In 2002, baseline data were collected on fatigue (Modified Fatigue Impact Scale), health-related quality of life (SF-36), and disability status (EDSS score). The EDSS scores were determined again at least three years later. Univariate and multivariate analysis were performed to determine the predictive value of different dimensions of fatigue and other variables (depression and SF- 36) on the change in disability status. Of the 196 patients, 106 (54%) patients had an unchanged status or improvement and 90 (46%) showed a worsening of disability. After three years, with control for gender, age, and baseline disability status, a high baseline level of physical fatigue was associated with a worsening of disability status, whereas a low baseline level of physical fatigue was associated with the absence of worsening of the EDSS score. Other dimensions of fatigue, depression and SF-36 were not associated with a worsening of disability. A patient’s perceived fatigue may be not only a clinically and psychosocially meaningful outcome but also a predictor of objective outcomes such as changes in disability status at three years.

International audience; According to neuropsychological evidence, a distributed network of regions of the ventral visual pathway - from the lateral occipital cortex to the temporal pole - supports face recognition. However, functional magnetic resonance imaging (fMRI) studies have generally confined ventral face-selective areas to the posterior section of the occipito-temporal cortex, i.e., the inferior occipital gyrus occipital face area (OFA) and the posterior and middle fusiform gyrus fusiform face area (FFA). There is recent evidence that intracranial electrical stimulation of these areas in the right hemisphere elicits face matching and recognition impairments (i.e., prosopagnosia) as well as perceptual face distortions. Here we report a case of transient inability to recognize faces following electrical stimulation of the right anterior fusiform gyrus, in a region located anteriorly to the FFA. There was no perceptual face distortion reported during stimulation. Although no fMRI face-selective responses were found in this region due to a severe signal drop-out as in previous studies, intracerebral face-selective event-related potentials and gamma range electrophysiological responses were found at the critical site of stimulation. These results point to a causal role in face recognition of the right anterior fusiform gyrus and more generally of face-selective areas located beyond the "core" face-processing network in the right ventral temporal cortex. It also illustrates the diagnostic value of intracerebral electrophysiological recordings and stimulation in understanding the neural basis of face recognition and visual recognition in general.

International audience; This case report on an epileptic patient suffering from a focal lesion at the junction of the right anterior insular cortex (AIC) and the adjacent inferior frontal cortex (IFC) provides the first evidence that damage to this brain region impairs temporal performance in a visual time reproduction task in which participants had to reproduce the presentation duration (3, 5 and 7 s) of emotionally-neutral and -negative pictures. Strikingly, as compared to a group of healthy subjects, the AIC/IFC case considerably overestimated reproduction times despite normal variability. The effect was obtained in all duration and emotion conditions. Such a distortion in time reproduction was not observed in four other epileptic patients without insular or inferior frontal damage. Importantly, the absolute extent of temporal over-reproduction increased in proportion to the magnitude of the target durations, which concurs with the scalar property of interval timing, and points to an impairment of time-specific rather than of non temporal (such as motor) mechanisms. Our data suggest that the disability in temporal reproduction of the AIC/IFC case would result from a distorted memory representation of the encoded duration, occurring during the process of storage and/or of recovery from memory and leading to a deviation of the temporal judgment during the reproduction task. These findings support the recent proposal that the anterior insular/inferior frontal cortices would be involved in time interval representation.

International audience; During intracerebral stimulation of the right inferior occipital cortex, a patient with refractory epilepsy was transiently impaired at discriminating two simultaneously presented photographs of unfamiliar faces. The critical electrode contact was located in the most posterior face-selective brain area of the human brain (right “occipital face area”, rOFA) as shown both by low- (ERP) and high-frequency (gamma) electrophysiological responses as well as a face localizer in fMRI. At this electrode contact, periodic visual presentation of 6 different faces by second evoked a larger electrophysiological periodic response at 6 Hz than when the same face identity was repeated at the same rate. This intracerebral EEG repetition suppression effect was markedly reduced when face stimuli were presented upside-down, a manipulation that impairs individual face discrimination. These findings provide original evidence for a causal relationship between the face-selective right inferior occipital cortex and individual face discrimination, independently of long-term memory representations. More generally, they support the functional value of electrophysiological repetition suppression effects, indicating that these effects can be used as an index of a necessary neural representation of the changing stimulus property.

As of yet, no consensus has been reached regarding cognitive impairment profiles in multiple sclerosis (MS) patients based on the MS type and disease duration. The main objective of this study was to describe cognitive impairment at the early stages of MS. The secondary objective was to compare cognitive performances in patients with relapsing remitting multiple sclerosis (RRMS), secondary progressive (SP) MS and primary progressive (PP) MS.The study included 128 MS patients and 63 healthy controls (HC). The study constituted five groups: early RR (ERR) (3 years); late RR (LRR) (10 years), SP, PP, and healthy Controls (HC). A neuropsychological assessment was performed including information processing speed (IPS), working memory, verbal episodic memory and executive functions.Compared to HC, only impairment in phonemic fluency was observed in ERR. Slowing IPS, impairment in working memory and phonemic fluency were shown in LRR. In progressive forms, deficits were observed in verbal episodic memory, in working memory, in flexibility, in semantic and phonemic fluencies, with a slowing IPS.Verbal fluency is impaired at early stage of RRMS, in this form of MS, impairment increased with MS duration, and distinct cognitive profiles were observed between chronic and progressive forms.

Introduction La presence de troubles cognitifs est maintenant etablie chez 30 a 50 % des patients atteints de sclerose laterale amyotrophique (SLA). Objectifs L’objectif principal de l’etude etait de rechercher des correlations entre les donnees de l’IRM de diffusion et les tests neuropsychologiques a l’inclusion et a un an. L’objectif secondaire etait de determiner la valeur predictive de l’IRM de diffusion sur la severite de la maladie. Patients et methodes Nous avons inclus des patients atteints de SLA non dements suivis dans le centre SLA de Nancy. Une evaluation clinique fonctionnelle (ALSFRS), des tests neuropsychologiques et une IRM de diffusion avec determination de la fraction d’anisotropie (FA) de differents faisceaux de substance blanche ont ete realises a l’inclusion et a un an. Resultats Vingt-trois patients ont ete inclus. La reconnaissance des emotions, la denomination, la memoire de travail et de recuperation etaient les plus atteintes. A un an, il a ete montre des correlations significatives entre memoire et diminution de la FA du fornix ; entre fonctions executives et diminution de FA du tractus corticospinal, du faisceau longitudinal inferieur et du fornix et entre reconnaissance des emotions et diminution de FA du tractus corticospinal. Il n’y avait aucune correlation entre les scores ALSFRS et les FA. Discussion Le lien entre les FA des faisceaux de substance blanche et l’atteinte cognitive est retrouve dans la litterature. Nous avons montre des correlations entre la memoire, les fonctions executives, la reconnaissance des emotions et differents faisceaux, mais uniquement a un an de l’inclusion. Conclusion Bien que les donnees soient heterogenes entre les etudes, l’IRM de diffusion pourrait etre un outil interessant dans la SLA apres standardisation des techniques.

SUMMARY: We describe 2 patients with unusual white matter cystic dilations, which could correspond to widening of the perivascular spaces. They underwent morphologic MR imaging with tractography, functional MR imaging (fMRI), and neuropsychological evaluation. fMRI examination showed no functional reorganization of cortical areas. Tractography showed an apparent decrease of white matter tract vectors into the regions of concern. Findings of the neuropsychological examination were normal. It seems that even an extensive cystic dilation of white matter does not deteriorate brain function.

Objectifs Etudier en IRM le retentissement anatomique et fonctionnel d’une dilatation kystique geante des espaces perivasculaires (EPV) de Virchow-Robin chez deux patients asymptomatiques. Materiels et methodes Decouverte fortuite d’une dilatation kystique geante des EPV encephaliques chez deux patients qui beneficiaient d’une IRM pour une autre pathologie (1er patient : parieto-occipitale gauche ; 2e patient : FI et gyrus cingulaire gauches). Ces deux patients ont beneficie d’une etude complementaire associant tractographie en tenseur de diffusion et IRM fonctionnelle, couplee a un bilan neuropsychologique. Resultats La dilatation kystique des EPV se traduit par une destruction des faisceaux de substance blanche, associee a une reorganisation anatomo-fonctionnelle des aires corticales. Conclusion La dilatation geante des EPV est extremement rare, et de decouverte fortuite car sans retentissement neuropsychologique. En effet, du fait d’un probable developpement tres precoce, il existe une reorganisation anatomo-fonctionnelle. L’etude en tractographie et en IRM fonctionnelle n’avait jusqu’alors, a notre connaissance, jamais ete realisee.