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ID 208 – Orienting network dysfunction in progressive multiple sclerosis
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Abstracts / Clinical Neurophysiology 127 (2016) e18–e132
ID 208 – Orienting network dysfunction in progressive multiple sclerosis—M.A. Chalah a,b, U. Palm a,c, R. Nguyen a,d, A. Créange a,d, J.-P. Lefaucheur a,b, S.S. Ayache a,b (a EA 4391, Excitabilité Nerveuse et Thérapeutique, Université Paris-Est-Créteil, France, b Service de Physiologie – Explorations Fonctionnelles, Hôpital Henri Mondor, Assistance Publique – Hôpitaux de Paris, France, c Department of Psychiatry, Psychotherapy and Psychosomatics, LudwigMaximilian University, Germany, d Service de Neurologie, Hôpital Henri Mondor, Assistance Publique – Hôpitaux de Paris, France) Objective: Attention is one of the frequently impaired cognitive domains in patients with multiple sclerosis (MS). The Attention Network Test (ANT) is a validated tool to assess the three main attentional networks: the alerting, orienting, and executive function networks. To our knowledge, ANT was not studied in progressive MS subtypes. Methods: 25 patients with primary or secondary progressive MS and 25 age and sex matched healthy controls were enrolled. The cognitive screening and attention evaluation were performed using the Symbol Digit Modality Test (SDMT) and ANT respectively. The statistical analysis was done using Mann-Whitney and Spearman rank tests. Results: Compared to healthy controls, MS patients had poorer performances on both tests. They also had an exclusive significant deficit in the orienting network. ANT parameters were positively correlated with the disability scores and the progressive phase duration. Conclusions: This is the first study to report an orientation deficit in progressive MS. Such findings can be attributed to the disease progression and the subsequent increase in the lesion load. Key message: Our study supports the value of ANT and SDMT in evaluating different cognitive aspects, and emphasizes the orienting network dysfunction in progressive MS. doi:10.1016/j.clinph.2015.11.239
ID 221 – Disturbed eye movement control in Parkinson’s disease correlates with intrinsic functional connectivity within cortical networks—M. Gorges, H.-P. Müller, A.C. Ludolph, E.H. Pinkhardt, J. Kassubek (Ulm University, Dept. of Neurology, Ulm, Germany) Objective: To investigate whether impaired eye movement control as a common non-motor manifestation in Parkinson’s disease (PD) is associated with alterations of intrinsic functional connectivity. Methods: We recorded smooth pursuit and saccadic eye movements using video-oculography and ‘resting-state’ fMRI in 31 PD patients and 22 matched healthy controls. Eye movement parameters were correlated with functional connectivity measures inbetween connectivity networks. Results: In agreement with the present literature, oculomotor deficits in PD included interrupted smooth pursuit, hypometric saccades, and increased error rate in anti-saccades. We demonstrated significant correlations between eye movement parameters and functional connectivity measures, i.e. the functional connectivity declined with disturbed eye movement performance. Connectivity between major nodes of the default mode network was strongly correlated with the rate of saccadic intrusions as a measure of executive function. Conclusions: Oculomotor deficits in PD appear to be predominantly associated with executive dysfunctions and to be attributable to impaired higher functional networks rather than to brainstem
oculomotor circuitry. These results support the notion that dopamine depletion alone is insufficient to explain executive oculomotor abnormalities in PD. Key message: Deficits in eye movement control in PD may reflect a behavioral correlate of altered intrinsic brain activity within cortical function networks. doi:10.1016/j.clinph.2015.11.240
ID 249 – Corrupted fractal organization of EEG topographical fluctuations predict disease state in minimally disabled multiple sclerosis patients—M. Gschwind a,b, D. Van De Ville c,d, M. Hardmeier e, P. Fuhr e, C. Michel b, M. Seeck a (a Department of Neurology, University Hospital Geneva, Geneva, Switzerland, b Functional Brain Mapping Laboratory, Department of Neuroscience, Biotech Campus, University of Geneva, Geneva, Switzerland, c Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland, d Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, e Department of Neurology, Hospital of the University of Basel, Basel, Switzerland) Objective: Topographical EEG analysis gives access to the coherent activation within global functional networks in resting-state. For these so-called microstates a temporal organization according to fractal structure has been demonstrated in healthy participants. Here we tested whether these fractal properties would be affected in multiple sclerosis (MS) patients. Methods: We acquired 256-channel EEG in 53 minimally-disable relapsing-remitting MS patients (mean age 37.6 y, EDSS 6 4, mean disease duration 9.9 y, 45 females), and 49 healthy controls (mean age 36.4 y, 33 females). We analyzed 5 min of wakefulness at rest, and isolated the 4 predominant topographies, well known from literature. Using a wavelet framework and detrended fluctuation analysis we estimated temporal fractality and long-range dependency. Results: We found significant differences between MS patients and controls in terms of a decreased Hurst exponent (p = 0.01), and an increased entropy (p = 0.01) in patients, indicating disturbed fractal order. Moreover, a high Hurst exponent strongly predicted a high depression score in patients (p < 0.000; R2 = 0.245), but not in controls. Conclusions: In MS patients, higher order temporal complexity of topographical EEG fluctuations is disturbed, predicting patient’s depression score. Key message: Features of temporal complexity in topographical EEG fluctuations could serve as a potential marker of brain state in relapsing-remitting MS. doi:10.1016/j.clinph.2015.11.241
ID 288 – Nociceptive flexion reflex responses in idiopathic Parkinson’ patients with pain—M. Sohtaog˘lu Sevindik a, H. Ergin Toktasß b, S. Özekmekçi a, M.E. Kızıltan a (a Neurology Department, Cerrahpasa Faculty of Medicine, Istanbul University, Istanbul, Turkey, b Neurology Department, Erenkoy Research and Training Hospital, Istanbul, Turkey) Background: Pain is a disturbing non-motor feature of Parkinson’s disease(PD), with a reported prevalence of 40–50%. We aimed to
Abstracts / Clinical Neurophysiology 127 (2016) e18–e132
ID 208 – Orienting network dysfunction in progressive multiple sclerosis—M.A. Chalah a,b, U. Palm a,c, R. Nguyen a,d, A. Créange a,d, J.-P. Lefaucheur a,b, S.S. Ayache a,b (a EA 4391, Excitabilité Nerveuse et Thérapeutique, Université Paris-Est-Créteil, France, b Service de Physiologie – Explorations Fonctionnelles, Hôpital Henri Mondor, Assistance Publique – Hôpitaux de Paris, France, c Department of Psychiatry, Psychotherapy and Psychosomatics, LudwigMaximilian University, Germany, d Service de Neurologie, Hôpital Henri Mondor, Assistance Publique – Hôpitaux de Paris, France) Objective: Attention is one of the frequently impaired cognitive domains in patients with multiple sclerosis (MS). The Attention Network Test (ANT) is a validated tool to assess the three main attentional networks: the alerting, orienting, and executive function networks. To our knowledge, ANT was not studied in progressive MS subtypes. Methods: 25 patients with primary or secondary progressive MS and 25 age and sex matched healthy controls were enrolled. The cognitive screening and attention evaluation were performed using the Symbol Digit Modality Test (SDMT) and ANT respectively. The statistical analysis was done using Mann-Whitney and Spearman rank tests. Results: Compared to healthy controls, MS patients had poorer performances on both tests. They also had an exclusive significant deficit in the orienting network. ANT parameters were positively correlated with the disability scores and the progressive phase duration. Conclusions: This is the first study to report an orientation deficit in progressive MS. Such findings can be attributed to the disease progression and the subsequent increase in the lesion load. Key message: Our study supports the value of ANT and SDMT in evaluating different cognitive aspects, and emphasizes the orienting network dysfunction in progressive MS. doi:10.1016/j.clinph.2015.11.239
ID 221 – Disturbed eye movement control in Parkinson’s disease correlates with intrinsic functional connectivity within cortical networks—M. Gorges, H.-P. Müller, A.C. Ludolph, E.H. Pinkhardt, J. Kassubek (Ulm University, Dept. of Neurology, Ulm, Germany) Objective: To investigate whether impaired eye movement control as a common non-motor manifestation in Parkinson’s disease (PD) is associated with alterations of intrinsic functional connectivity. Methods: We recorded smooth pursuit and saccadic eye movements using video-oculography and ‘resting-state’ fMRI in 31 PD patients and 22 matched healthy controls. Eye movement parameters were correlated with functional connectivity measures inbetween connectivity networks. Results: In agreement with the present literature, oculomotor deficits in PD included interrupted smooth pursuit, hypometric saccades, and increased error rate in anti-saccades. We demonstrated significant correlations between eye movement parameters and functional connectivity measures, i.e. the functional connectivity declined with disturbed eye movement performance. Connectivity between major nodes of the default mode network was strongly correlated with the rate of saccadic intrusions as a measure of executive function. Conclusions: Oculomotor deficits in PD appear to be predominantly associated with executive dysfunctions and to be attributable to impaired higher functional networks rather than to brainstem
oculomotor circuitry. These results support the notion that dopamine depletion alone is insufficient to explain executive oculomotor abnormalities in PD. Key message: Deficits in eye movement control in PD may reflect a behavioral correlate of altered intrinsic brain activity within cortical function networks. doi:10.1016/j.clinph.2015.11.240
ID 249 – Corrupted fractal organization of EEG topographical fluctuations predict disease state in minimally disabled multiple sclerosis patients—M. Gschwind a,b, D. Van De Ville c,d, M. Hardmeier e, P. Fuhr e, C. Michel b, M. Seeck a (a Department of Neurology, University Hospital Geneva, Geneva, Switzerland, b Functional Brain Mapping Laboratory, Department of Neuroscience, Biotech Campus, University of Geneva, Geneva, Switzerland, c Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland, d Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, e Department of Neurology, Hospital of the University of Basel, Basel, Switzerland) Objective: Topographical EEG analysis gives access to the coherent activation within global functional networks in resting-state. For these so-called microstates a temporal organization according to fractal structure has been demonstrated in healthy participants. Here we tested whether these fractal properties would be affected in multiple sclerosis (MS) patients. Methods: We acquired 256-channel EEG in 53 minimally-disable relapsing-remitting MS patients (mean age 37.6 y, EDSS 6 4, mean disease duration 9.9 y, 45 females), and 49 healthy controls (mean age 36.4 y, 33 females). We analyzed 5 min of wakefulness at rest, and isolated the 4 predominant topographies, well known from literature. Using a wavelet framework and detrended fluctuation analysis we estimated temporal fractality and long-range dependency. Results: We found significant differences between MS patients and controls in terms of a decreased Hurst exponent (p = 0.01), and an increased entropy (p = 0.01) in patients, indicating disturbed fractal order. Moreover, a high Hurst exponent strongly predicted a high depression score in patients (p < 0.000; R2 = 0.245), but not in controls. Conclusions: In MS patients, higher order temporal complexity of topographical EEG fluctuations is disturbed, predicting patient’s depression score. Key message: Features of temporal complexity in topographical EEG fluctuations could serve as a potential marker of brain state in relapsing-remitting MS. doi:10.1016/j.clinph.2015.11.241
ID 288 – Nociceptive flexion reflex responses in idiopathic Parkinson’ patients with pain—M. Sohtaog˘lu Sevindik a, H. Ergin Toktasß b, S. Özekmekçi a, M.E. Kızıltan a (a Neurology Department, Cerrahpasa Faculty of Medicine, Istanbul University, Istanbul, Turkey, b Neurology Department, Erenkoy Research and Training Hospital, Istanbul, Turkey) Background: Pain is a disturbing non-motor feature of Parkinson’s disease(PD), with a reported prevalence of 40–50%. We aimed to