Long-term outcome after cognitive and behavioral regression in nonlesional epilepsy with continuous spike-waves during slow-wave sleep.

PURPOSE: To present the long-term follow-up of 10 adolescents and young adults with documented cognitive and behavioral regression as children due to nonlesional focal, mainly frontal, epilepsy with continuous spike-waves during slow wave sleep (CSWS). METHODS: Past medical and electroencephalography (EEG) data were reviewed and neuropsychological tests exploring main cognitive functions were administered. KEY FINDINGS: After a mean duration of follow-up of 15.6 years (range, 8-23 years), none of the 10 patients had recovered fully, but four regained borderline to normal intelligence and were almost independent. Patients with prolonged global intellectual regression had the worst outcome, whereas those with more specific and short-lived deficits recovered best. The marked behavioral disorders resolved in all but one patient. Executive functions were neither severely nor homogenously affected. Three patients with a frontal syndrome during the active phase (AP) disclosed only mild residual executive and social cognition deficits. The main cognitive gains occurred shortly after the AP, but qualitative improvements continued to occur. Long-term outcome correlated best with duration of CSWS. SIGNIFICANCE: Our findings emphasize that cognitive recovery after cessation of CSWS depends on the severity and duration of the initial regression. None of our patients had major executive and social cognition deficits with preserved intelligence, as reported in adults with early destructive lesions of the frontal lobes. Early recognition of epilepsy with CSWS and rapid introduction of effective therapy are crucial for a best possible outcome.

RADIC II: a fault tolerant architecture with flexible dynamic redundancy

The demand for computational power has been leading the improvement of the High Performance Computing (HPC) area, generally represented by the use of distributed systems like clusters of computers running parallel applications. In this area, fault tolerance plays an important role in order to provide high availability isolating the application from the faults effects. Performance and availability form an undissociable binomial for some kind of applications. Therefore, the fault tolerant solutions must take into consideration these two constraints when it has been designed. In this dissertation, we present a few side-effects that some fault tolerant solutions may presents when recovering a failed process. These effects may causes degradation of the system, affecting mainly the overall performance and availability. We introduce RADIC-II, a fault tolerant architecture for message passing based on RADIC (Redundant Array of Distributed Independent Fault Tolerance Controllers) architecture. RADIC-II keeps as maximum as possible the RADIC features of transparency, decentralization, flexibility and scalability, incorporating a flexible dynamic redundancy feature, allowing to mitigate or to avoid some recovery side-effects.

Alcohol and relatively pure cannabis use, but not schizotypy, are associated with cognitive attenuations

Elevated schizotypy relates to similar cognitive attenuations as seen in psychosis and cannabis/polydrug use. Also, in schizotypal populations cannabis and polydrug (including licit drug) use are enhanced.These cognitive attenuations may therefore either be a behavioral marker of psychotic (-like) symptoms or the consequence of enhanced drug use in schizotypal populations.To elucidate this, we investigated the link between cognitive attenuation and cannabis use in largely pure cannabis users (35) and non-using controls (48), accounting for the potential additional influence of both schizotypy and licit drug use (alcohol, nicotine). Cognitive attenuations commonly seen in psychosis were associated with cannabis and alcohol use, but not schizotypy. Future studies should therefore consider (i) non-excessive licit substance use (e.g., alcohol) in studies investigating the effect of cannabis use on cognition and (ii) both enhanced illicit and licit substance use in studies investigating cognition in schizotypal populations.

Performances et défaillances du sujet cérébral : regard anthropologique sur la plasticité cérébrale, les neurosciences et la clinique de la dégénérescence cognitive

Introduction 1.1 Le sujet cérébral, rencontre entre le biologique et le social L'objectif de ce travail est d'éclairer une des voies par lesquelles le phénomène anthropologique de l'individualité prend corps au sein de l'environnement contemporain. L'individualisme est compris comme les divers processus par lesquels la détermination du sujet tend à s'autonomiser des appartenances préconstituées. Il est la forme sociologique qui gouverne la façon contemporaine de faire société depuis l'avènement de la «modernité ». Le choix de l'angle de la cérébralité pour aborder la question de recherche repose sur le postulat qu'une des particularités culturelles de la figure du sujet individuel contemporain est la tendance à attribuer aux mécanismes cérébraux le rôle déterminant dans la constitution de la subjectivité du sujet. Dès lors, si aujourd'hui, penser le cerveau c'est penser l'humain, il s'agit d'un phénomène anthropologique qui demande à être explicité. Il m'appartient de démontrer que le champ des neurosciences se profile comme révélateur privilégié pour observer comment penser l'individualité concorde avec l'établissement de vérités relatives au cérébral' . Faire l'anthropologie du proche et de l'actuel a ses intérêts mais comporte aussi des risques. La perte de ce qui faisait le moteur de la recherche anthropologique -l'altérité donnée des sujets de son observation - a été compensée par l'émergence de nouveaux objets de travail et par des reconfigurations des rapports que l'anthropologue entretient avec son terrain. Le renouvellement du cadre de réflexion opéré par l'anthropologie au cours du siècle écoulé suit les transformations des pratiques sociales, culturelles et économiques qui s'opèrent au niveau mondial. L'échelle désormais planétaire de la circulation des acteurs sociaux et des objets de savoir a forcé la discipline à revoir la grille de lecture qui a longtemps opposé sociétés traditionnelles à sociétés modernes. La prise de conscience de la caducité du grand partage a engagé les anthropologues à s'intéresser à des phénomènes en rapport avec des problèmes rencontrés au sein de leur propre collectif et, dans le même mouvement, les a amenée à repenser les articulations entre le global et le local, le particulier et l'universel. Le bouleversement heuristique généré par ce repositionnement n'est toutefois pas exempt de nouvelles difficultés pour la recherche ethnographique. En se posant le défi d'étudier des traits culturels propres à sa société d'appartenance, l'anthropologie s'ouvre à des terrains enquête sur la façon dont, dans le monde occidental, le constat toujours plus pesant de la discordance entre les phénomènes de vieillissement cognitif et l'allongement de l'espérance de vie est traité. Dans une démarche ethnographique, il s'agit de voir quelles sont les logiques d'action et les pratiques sociales développées en réponse à ces inadéquations. La thématique impose une navigation entre des domaines théoriques spécialisés et des champs d'activités possédant chacun leurs cadres de référence. Une telle entreprise suppose une multiplication des systèmes de référence devant être pris en compte. Toutes les disciplines approchées au cours de ce travail abondent en métaphores utiles à la mise en ordre de leur pensée et à la description de leurs objets de travail. Toutefois, faire résonner entre elles les différentes «cultures épistémiques » (Knorr-Cetina, 1999) pour mieux faire apparaître la trame sociale qui constitue leur arrière-fond équivaut souvent à forcer le trait. Le sens des mots varie selon leurs champs d'application et l'exercice de la mise en résonance peut s'avérer périlleux. Je me suis efforcée tout au long de ces pages de préciser de quel point de vue les énoncés considérés sont formulés. L'analyse anthropologique étant guidée par la recherche des points de liaison entre les différents registres, la démarche est forcément limitée dans le niveau d'approfondissement auquel elle peut tendre. Elle risque de décevoir les lecteurs experts dans les domaines soumis à la grille de lecture de cette discipline, non familiers avec les concepts anthropologiques. Il est probable qu'un certain flou subsiste dans la façon dont ces énoncés sont décris par rapport au traitement dont ils sont l'objet dans leurs disciplines respectives. Si on perd de vue la préoccupation centrale de l'anthropologie, consistant à éclairer le système de valeurs commun sous-tendant les pratiques sociales observées, la lecture d'un tel travail risque effectivement de rater son but. En revanche, en acceptant d'emblée de se prêter à un décentrement par rapport à son modèle disciplinaire, le lecteur doit pouvoir appréhender des aspects intéressant ses propres pratiques. S'intéresser à ce qui relie les savoirs et les pratiques au sein d'un monde commun, voilà un programme heuristique qui va à l'encontre de la logique de spécialisation.

Treatment motivation in adolescents with psychosis or at high risk: Determinants and impact on improvements in symptoms and cognitive functioning, preliminary results.

Abstract Low motivation is frequent in chronic disorders such as psychosis and may limit treatment efficacy. Although some evidence supports this view in adults, few studies so far have focused on adolescents. We assessed the impact of baseline symptoms, cognitive deficits and cognitive treatment characteristics on treatment motivation (TM), and examined whether TM affected treatment outcome. Twenty-eight adolescents with psychotic disorders participated in 16 sessions of computerized cognitive remediation or games. TM was assessed for each session. Lower TM was predicted by more severe symptoms at baseline, and was associated with smaller improvements in symptoms and both cognitive and psychosocial functioning at the end of the intervention. Experiencing success in the treatment exercises enhanced TM in all patients.

Intraoperative cerebral perfusion and postoperative cognitive dysfunction in geriatric patients

Background: Inadequate intraoperative cerebral perfusion has been suggested as a possible cause of postoperative cognitive dysfunction (POCD). Methods: We investigated 35 patients aged 65 or older undergoing elective major non-cardiac surgery under standardized general anaesthesia (thiopental, sevoflurane, fentanyl, atracurium). Intraoperative cerebral perfusion was monitored with transcranial Doppler, and near-infrared spectroscopy (NIRS). Arterial blood pressure was monitored continuously with a Finapres device. Mx, an index allowing continuous monitoring of cerebrovascular autoregulation based on the changes in mean arterial blood pressure (MAP) and cerebral blood flow velocity was calculated. Mx >0.5 was defined as disturbed cerebrovascular autoregulation. Cognitive function was measured preoperatively and 7 days postoperatively using the CERAD-NAB Plus test battery. A postoperative decline >1 z-score in at least two of the tested domains was defined as POCD. Data are shown as mean } SD. Results: Mean age was 75 } 7 yrs. Sixteen patients (46%) developed POCD. These patients were older (77 } 8 vs 73 } 7 yrs), had lower MAP (77 } 12 vs 81 } 11 mm Hg), lower cerebral tissue oxygenation indices measured by NIRS (66.8 } 6.0 vs 68.6 } 4.3%) and less efficient cerebrovascular autoregulation (Mx 0.54 } 0.17 and 0.44 } 0.22) than patients without POCD. Disturbed intraoperative cerebrovascular autoregulation was found more often (56 vs 37%) in patients with POCD. However, none of these differences reached statistical significance. Conclusions: Our data show a trend towards subtle changes in intraoperative cerebral perfusion in elderly patients who develop POCD. However, a cause effect relationship must not be assumed and a greater number of patients needs to be investigated patients. However, more patients need to be investigated to confirm and characterize these differences.

Entrepreneurial intention, cognitive social capital and culture: empirical anaylisis for Spain and Taiwan

The main purpose of this paper is building a research model to integrate the socioeconomic concept of social capital within intentional models of new firm creation. Nevertheless, some researchers have found cultural differences between countries and regions to have an effect on economic development. Therefore, a second objective of this study is exploring whether those cultural differences affect entrepreneurial cognitions. Research design and methodology: Two samples of last year university students from Spain and Taiwan are studied through an Entrepreneurial Intention Questionnaire (EIQ). Structural equation models (Partial Least Squares) are used to test the hypotheses. The possible existence of differences between both sub-samples is also empirically explored through a multigroup analysis. Main outcomes and results: The proposed model explains 54.5% of the variance in entrepreneurial intention. Besides, there are some significant differences between both subsamples that could be attributed to cultural diversity. Conclusions: This paper has shown the relevance of cognitive social capital in shaping individuals’ entrepreneurial intentions across different countries. Furthermore, it suggests that national culture could be shaping entrepreneurial perceptions, but not cognitive social capital. Therefore, both cognitive social capital and culture (made up essentially of values and beliefs), may act together to reinforce the entrepreneurial intention.

System analysis of a Peer-to-Peer Video-on-Demand architecture: Kangaroo

Architectural design and deployment of Peer-to-Peer Video-on-Demand (P2PVoD) systems which support VCR functionalities is attracting the interest of an increasing number of research groups within the scientific community; especially due to the intrinsic characteristics of such systems and the benefits that peers could provide at reducing the server load. This work focuses on the performance analysis of a P2P-VoD system considering user behaviors obtained from real traces together with other synthetic user patterns. The experiments performed show that it is feasible to achieve a performance close to the best possible. Future work will consider monitoring the physical characteristics of the network in order to improve the design of different aspects of a VoD system.

SUCLG2 identified as both a determinator of CSF Aβ1-42 levels and an attenuator of cognitive decline in Alzheimer's disease.

Cerebrospinal fluid amyloid-beta 1-42 (Aβ1-42) and phosphorylated Tau at position 181 (pTau181) are biomarkers of Alzheimer's disease (AD). We performed an analysis and meta-analysis of genome-wide association study data on Aβ1-42 and pTau181 in AD dementia patients followed by independent replication. An association was found between Aβ1-42 level and a single-nucleotide polymorphism in SUCLG2 (rs62256378) (P = 2.5×10(-12)). An interaction between APOE genotype and rs62256378 was detected (P = 9.5 × 10(-5)), with the strongest effect being observed in APOE-ε4 noncarriers. Clinically, rs62256378 was associated with rate of cognitive decline in AD dementia patients (P = 3.1 × 10(-3)). Functional microglia experiments showed that SUCLG2 was involved in clearance of Aβ1-42.

Behavioral and psychological symptoms and cognitive decline in patients with amnestic MCI and mild AD: a two-year follow-up study.

BACKGROUND: Mild cognitive impairment (MCI) has been defined as a transitional state between normal aging and dementia. In many cases, MCI represents an early stage of developing cognitive impairment. Patients diagnosed with MCI do not meet the criteria for dementia as their general intellect and everyday activities are preserved, although minor changes in instrumental activities of daily living (ADL) may occur. However, they may exhibit significant behavioral and psychological signs and symptoms (BPS), also frequently observed in patients with Alzheimer's disease (AD). Hence, we wondered to what extent specific BPS are associated with cognitive decline in participants with MCI or AD. METHODS: Our sample consisted of 164 participants, including 46 patients with amnestic (single or multi-domain) MCI and 54 patients with AD, as well as 64 control participants without cognitive disorders. Global cognitive performance, BPS, and ADL were assessed using validated clinical methods at baseline and at two-year follow-up. RESULTS: The BPS variability over the follow-up period was more pronounced in the MCI group than in patients with AD: some BPS improve, others occur newly or worsen, while others still remain unchanged. Moreover, specific changes in BPS were associated with a rapid deterioration of the global cognitive level in MCI patients. In particular, an increase of euphoria, eating disorders, and aberrant motor behavior, as well as worsened sleep quality, predicted a decline in cognitive functioning. CONCLUSIONS: Our findings confirm a higher variability of BPS over time in the MCI group than in AD patients. Moreover, our results provide evidence of associations between specific BPS and cognitive decline in the MCI group that might suggest a risk of conversion of individuals with amnestic MCI to AD.

Evaluation of a summary score of cognitive performance for use in trials in perioperative and critical care.

Background/Aims: Cognitive dysfunction after medical treatment is increasingly being recognized. Studies on this topic require repeated cognitive testing within a short time. However, with repeated testing, practice effects must be expected. We quantified practice effects in a demographically corrected summary score of a neuropsychological test battery repeatedly administered to healthy elderly volunteers. Methods: The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Neuropsychological Assessment Battery (for which a demographically corrected summary score was developed), phonemic fluency tests, and trail-making tests were administered in healthy volunteers aged 65 years or older on days 0, 7, and 90. This battery allows calculation of a demographically adjusted continuous summary score. Results: Significant practice effects were observed in the CERAD total score and in the word list (learning and recall) subtest. Based on these volunteer data, we developed a threshold for diagnosis of postoperative cognitive dysfunction (POCD) with the CERAD total score. Conclusion: Practice effects with repeated administration of neuropsychological tests must be accounted for in the interpretation of such tests. Ignoring practice effects may lead to an underestimation of POCD. The usefulness of the proposed demographically adjusted continuous score for cognitive function will have to be tested prospectively in patients.

Programme de remédiation cognitive pour patients présentant une schizophrénie ou un trouble associé (Recos) : résultats préliminaires [Cognitive remediation program for individuals living with schizophrenia (Recos): preliminary results].

BACKGROUND: Nowadays, cognitive remediation is widely accepted as an effective treatment for patients with schizophrenia. In French-speaking countries, techniques used in cognitive remediation for patients with schizophrenia have been applied from those used for patients with cerebral injury. As cognitive impairment is a core feature of schizophrenia, the Département de psychiatrie du CHUV in Lausanne (DP-CHUV) intended to develop a cognitive remediation program for patients with a schizophrenia spectrum disease (Recos-Vianin, 2007). Numerous studies show that the specific cognitive deficits greatly differ from one patient to another. Consequently, Recos aims at providing individualized cognitive remediation therapy. In this feasibility trial, we measured the benefits of this individualized therapy for patients with schizophrenia. Before treatment, the patients were evaluated with a large battery of cognitive tests in order to determine which of the five specific training modules - Verbal memory, visuospatial memory and attention, working memory, selective attention, reasoning - could provide the best benefit depending on their deficit. OBJECTIVES: The study was designed to evaluate the benefits of the Recos program by comparing cognitive functioning before and after treatment. METHOD: Twenty-eight patients with schizophrenia spectrum disorders (schizophrenia [n=18], schizoaffective disorder [n=5], schizotypal disorder [n=4], schizophreniform disorder [n=1], DSM-IV-TR) participated in between one and three of the cognitive modules. The choice of the training module was based on the results of the cognitive tests obtained during the first evaluation. The patients participated in 20 training sessions per module (one session per week). At the end of the training period, the cognitive functioning of each patient was reevaluated by using the same neuropsychological battery. RESULTS: The results showed a greater improvement in the cognitive functions, which were specifically trained, compared to the cognitive functions, which were not trained. However, an improvement was also observed in both types of cognitive functions, suggesting an indirect cognitive gain. CONCLUSION: In our view, the great heterogeneity of the observed cognitive deficits in schizophrenia necessitates a detailed neuropsychological investigation as well as an individualized cognitive remediation therapy. These preliminary results need to be confirmed with a more extended sample of patients.