Swiss Epilepsy Center

Zürich, Switzerland

Swiss Epilepsy Center

Zürich, Switzerland
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Huppertz H.-J.,Swiss Epilepsy Center | Kroll-Seger J.,Swiss Epilepsy Center | Kloppel S.,Section of Gerontopsychiatry and Neuropsychology | Ganz R.E.,Swiss Epilepsy Center | Kassubek J.,University of Ulm
NeuroImage | Year: 2010

The intra- and inter-scanner variability of an automated method for MRI-based volumetry was investigated. Using SPM5 algorithms and predefined masks derived from a probabilistic whole-brain atlas, this method allows to determine the volumes of various brain structures (e.g., hemispheres, lobes, cerebellum, basal ganglia, grey and white matter etc.) in single subjects in an observer-independent fashion. A healthy volunteer was scanned three times at six different MRI scanners (including different vendors and field strengths) to calculate intra- and inter-scanner volumetric coefficients of variation (CV). The mean intra-scanner CV values per brain structure ranged from 0.50% to 4.4% (median, 0.89%), while the inter-scanner CV results varied between 0.66% and 14.7% (median, 4.74%). The overall (= combined intra- and inter-scanner) variability of measurements was only marginally higher, with CV results of 0.87-15.1% (median, 4.80%). Furthermore, the minimum percentage volume difference for detecting a significant volume change between two volume measurements in the same subject was calculated for each substructure. For example, for the total brain volume, mean intra-scanner, inter-scanner, and overall CV results were 0.50%, 3.78%, and 3.80%, respectively, and the cut-offs for significant volume changes between two measurements in the same subject amounted to 1.4% for measurements on the same scanner and 10.5% on different scanners. These findings may be useful for planning and assessing volumetric studies in neurological diseases, for the differentiation of certain patterns of atrophy, or for longitudinal studies monitoring the course of a disease and potential therapeutic effects. © 2009 Elsevier Inc. All rights reserved.

Broicher S.D.,Swiss Epilepsy Center | Kuchukhidze G.,Innsbruck Medical University | Grunwald T.,Swiss Epilepsy Center | Kramer G.,Swiss Epilepsy Center | And 2 more authors.
Neuropsychologia | Year: 2012

Specific interictal personality characteristics in epilepsy, sometimes referred to as "Waxman-Geschwind Syndrome", have been recognized for centuries and extensively described. Despite the persevering clinical impression that patients with mesial temporal lobe epilepsies (MTLE) suffer from problems in communication and interpersonal relations, uncertainties and controversies remain as to the precise origin of these psychosocial difficulties. Here, we investigated social-cognitive and decision-making abilities using a set of tasks that combine behavioural and psychological measures of social and emotional variables to answer the question of whether patients with MTLE are specifically impaired in social cognition compared to both an epilepsy and a healthy control group. MTLE patients, an epilepsy control group (extra-MTLE; patients with epilepsy, not originating within the frontal or mesial temporal lobe) and healthy controls (HC) were assessed according to their general cognitive status as well as with our Social Cognition Battery, which included tests of basic processes of social cognition, theory of mind, decision making, and various aspects of psychopathology and quality of life. MTLE patients were significantly impaired compared to HC on most measures of the Social Cognition Battery. MTLE patients were predominantly impaired in general emotion recognition compared to extra-MTLE patients. Performance in the epilepsy control group, although not significantly differing from performance in either the MTLE or the healthy control group, lay between these two groups. MTLE can be considered a significant risk factor for the development of deficits in social cognition beyond weaknesses that might be associated with epilepsy as a stigmatized chronic neurological disorder. The presence of deficits in social cognition may explain various behavioural symptoms that have historically driven concepts such as "epileptic personality" or "interictal personality disorder" and may indicate new routes for therapeutic interventions. © 2011 Elsevier Ltd.

Engel A.K.,University of Hamburg | Maye A.,University of Hamburg | Kurthen M.,Swiss Epilepsy Center | Konig P.,University of Hamburg | Konig P.,University of Osnabrück
Trends in Cognitive Sciences | Year: 2013

In cognitive science, we are currently witnessing a 'pragmatic turn', away from the traditional representation-centered framework towards a paradigm that focuses on understanding cognition as 'enactive', as skillful activity that involves ongoing interaction with the external world. The key premise of this view is that cognition should not be understood as providing models of the world, but as subserving action and being grounded in sensorimotor coupling. Accordingly, cognitive processes and their underlying neural activity patterns should be studied primarily with respect to their role in action generation. We suggest that such an action-oriented paradigm is not only conceptually viable, but already supported by much experimental evidence. Numerous findings either overtly demonstrate the action-relatedness of cognition or can be re-interpreted in this new framework. We argue that new vistas on the functional relevance and the presumed 'representational' nature of neural processes are likely to emerge from this paradigm. © 2013 Elsevier Ltd.

Mecklinger A.,Saarland University | Kriukova O.,Saarland University | Muhlmann H.,Karlsruhe University of Arts and Design | Grunwald T.,Swiss Epilepsy Center | Grunwald T.,University of Zürich
Cognitive Neuroscience | Year: 2014

Visual object identification is modulated by perceptual experience. In a cross-cultural ERP study we investigated whether cultural expertise determines how buildings that vary in their ranking between high and low according to the Western architectural decorum are perceived. Two groups of German and Chinese participants performed an object classification task in which high- and low-ranking Western buildings had to be discriminated from everyday life objects. ERP results indicate that an early stage of visual object identification (i.e., object model selection) is facilitated for high-ranking buildings for the German participants, only. At a later stage of object identification, in which object knowledge is complemented by information from semantic and episodic long-term memory, no ERP evidence for cultural differences was obtained. These results suggest that the identification of architectural ranking is modulated by culturally specific expertise with Western-style architecture already at an early processing stage. © 2013 Taylor & Francis.

Frings L.,Albert Ludwigs University of Freiburg | Mader I.,Albert Ludwigs University of Freiburg | Landwehrmeyer B.G.,University of Ulm | Weiller C.,Albert Ludwigs University of Freiburg | And 2 more authors.
Human Brain Mapping | Year: 2012

A novel method of automated MRI volumetry was used to study regional atrophy and disease progression in repeated MRI measurements of patients with frontotemporal lobar degeneration (FTLD). Fifty-nine structural MRI data sets of 17 clinically diagnosed FTLD patients were acquired over up to 30 months in intervals of 6 months and compared with data of 30 age-matched healthy controls. Patients were further subgrouped into behavioral variant FTLD (bvFTLD), progressive nonfluent aphasia (PNFA), and semantic dementia (SemD). Gray matter (GM) volumes of frontal lobes (FL) and temporal lobes (TL) were determined by voxel-based volumetry based on SPM5 algorithms and a probabilistic brain atlas. MRI volumetry revealed frontal and temporal GM atrophy across FTLD patients, with further progression over time. Significant side asymmetry of TL volumes was found in SemD. The ratio of TL to FL volumes was significantly reduced in SemD and increased in bvFTLD. Using this ratio, 6/7 SemD patients and 5/6 bvFTLD patients could be correctly differentiated. TL/FL ratios in bvFTLD and SemD further diverged significantly over a time span of only 6 months. Rates of temporal GM loss per 6 months were 3-4% in SemD, and 2.5% for frontal GM loss in bvFTLD, and thereby clearly exceeded published cerebral volume loss in healthy elderly subjects. The study presents a fully automated, observer-independent volumetric assessment of regional atrophy which allows differentiation of FTLD subgroups. Its sensitivity for atrophy progression-even in such short intervals like 6 months-might benefit future clinical trials as treatment outcome measure. ©; 2011 Wiley-Liss, Inc.

Hoglinger G.U.,University of Marburg | Hoglinger G.U.,TU Munich | Hoglinger G.U.,German Center for Neurodegenerative Diseases | Huppertz H.-J.,Swiss Epilepsy Center | And 5 more authors.
Movement Disorders | Year: 2014

It is believed that glycogen synthase kinase-3 hyperphosphorylates tau protein in progressive supranuclear palsy (PSP). The Tau Restoration on PSP (TAUROS) trial assessed the glycogen synthase kinase-3 inhibitor tideglusib as potential treatment. For the magnetic resonance imaging (MRI) substudy reported here, we assessed the progression of brain atrophy. TAUROS was a multinational, phase 2, double-blind, placebo-controlled trial in patients with mild-to-moderate PSP who were treated with oral tideglusib (600 mg or 800 mg daily) or with placebo for 1 year. A subset of patients underwent baseline and 52-week MRI. Automated, observer-independent, atlas-based, and mask-based volumetry was done on high-resolution, T1-weighted, three-dimensional data. For primary outcomes, progression of atrophy was compared both globally (brain, cerebrum) and regionally (third ventricle, midbrain, pons) between the active and placebo groups (Bonferroni correction). For secondary outcomes, 15 additional brain structures were explored (Benjamini & Yekutieli correction). In total, MRIs from 37 patient were studied (placebo group, N = 9; tideglusib 600 mg group, N = 19; tideglusib 800 mg group, N = 9). The groups compared well in their demographic characteristics. Clinical results showed no effect of tideglusib over placebo. Progression of atrophy was significantly lower in the active group than in the placebo group for the brain (mean ± standard error of the mean: -1.3% ± 1.4% vs. -3.1% ± 2.3%, respectively), cerebrum (-1.3% ± 1.5% vs. -3.2% ± 2.1%, respectively), parietal lobe (-1.6% ± 1.9% vs. -4.1% ± 3.0%, respectively), and occipital lobe (-0.3% ± 1.8% vs. -2.7% ± 3.2%, respectively). A trend toward reduced atrophy also was observed in the frontal lobe, hippocampus, caudate nucleus, midbrain, and brainstem. In patients with PSP, tideglusib reduced the progression of atrophy in the whole brain, particularly in the parietal and occipital lobes. © 2014 International Parkinson and Movement Disorder Society.

Reuber M.,University of Sheffield | Kurthen M.,Swiss Epilepsy Center
Behavioural Neurology | Year: 2011

Non-epileptic attack disorder (NEAD) is one of the most important differential diagnoses of epilepsy. Impairment of consciousness is the key feature of non-epileptic attacks (NEAs). The first half of this review summarises the clinical research literature featuring observations relating to consciousness in NEAD. The second half places this evidence in the wider context of the recent discourse on consciousness in neuroscience and the philosophy of mind. We argue that studies of consciousness should not only distinguish between the 'level' and 'content' of consciousness but also between 'phenomenal consciousness' (consciousness of states it somehow "feels to be like") and 'access consciousness' (having certain 'higher' cognitive processes at one's disposal). The existing evidence shows that there is a great intra- and interindividual variability of NEA experience. However, in most NEAs phenomenal experience - and, as a precondition for that experience, vigilance or wakefulness - is reduced to a lesser degree than in those epileptic seizures involving impairment of consciousness. In fact, complete loss of "consciousness" is the exception rather than the rule in NEAs. Patients, as well as external observers, may have a tendency to overestimate impairments of consciousness during the seizures.

Kramer G.,Swiss Epilepsy Center
Epilepsia | Year: 2013

Placebo effects in the therapy of epilepsy were already known before the introduction of effective antiepileptic drugs (AEDs). They have physiologic correlates, and are even stronger in other neurologic disorders such as pain. Placebo effects in epilepsy have many facets. Our understanding of this phenomenon has increased in the last two decades: placebo effects are stronger in children than in adults, and may be culture- and setting-dependent; and impressive placebo effects occur in animals with epilepsy as well. More research is needed to fully elucidate the mechanism of placebo effects in epilepsy care, particularly as we go forth with studies addressing the issue of pharmacoresistance. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

Schmutz M.,Swiss Epilepsy Center
Epilepsy and Behavior | Year: 2013

Dissociative seizures are commonly recognized as both a challenging and a poorly understood condition. Though research and publication activity is high, advances in knowledge and insight seem only moderate in recent years. This review focuses on some relevant problematic issues, which might account for a still unsatisfactory research state. A general tendency to deal with dissociative seizures as an assumed disorder in its own nosological right and not as a sole symptom of an underlying psychiatric disorder is most likely one of the major roots of the problem. Unfavorable impacts of this confusion pertaining to clinical management, therapy, and outcome of dissociative seizures are discussed. An alternative point of view, based on the immanent psychiatric and psychodynamic roots of dissociative seizures, is considered.© 2013 Elsevier Inc.

Muller H.-P.,University of Ulm | Unrath A.,University of Ulm | Huppertz H.-J.,Swiss Epilepsy Center | Ludolph A.C.,University of Ulm | Kassubek J.,University of Ulm
Amyotrophic Lateral Sclerosis | Year: 2012

This study was designed to investigate differences of white matter (WM) involvement patterns in various motor neuron disorders (MND) by use of diffusion tensor imaging (DTI).DTI was acquired in ALS (n = 20), primary lateral sclerosis (n = 20), pure hereditary spastic paraparesis (HSP) (n = 20), and complicated HSP (n = 12). The data analysis was performed by voxelwise comparison of fractional anisotropy (FA) maps at group level together with fibre tracking in regions of interest (ROI) accompanied by tractwise fractional anisotropy statistics. DTI analysis revealed widespread patterns of alterations with a predominant deterioration of the motor system. These alterations encompassed, as the key structures, not only the corticospinal tracts (CST) but also distinct areas of the corpus callosum (CC), in particular its motor segment III. In conclusion, whole brain-based and tract-based DTI analysis was able to define a distinct WM pathoanatomy of different MND. These results may serve as an additional guidance in the identification of MRI-based parameters by showing a consistent CST and CC involvement, with differences in the extent of pathology, across a range of clinically different disorders. For potential future developments in MRI diagnostics in MND, a (perhaps multiparametric) ROI-based approach should include CST and the CC motor segment. © 2012 Informa Healthcare.

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