15-Sensory and cognitive processing of visual stimuli in adolescents with type 1 diabetes mellitus: Electrophysiological study

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Abstracts / Clinical Neurophysiology 129 (2018) e7–e13

12-Distinct between-network functional connectivity changes in Parkinson’s disease related to cognition: A follow-up study— P. Klobusiakova 1, R. Marecek 2,3, I. Rektorova 1,2 (1 ANRG CEITEC MU, Czech Republic , 2 Neurology FNUSA, Brno, Czech Republic , 3 MAFIL CEITEC MU, Czech Republic) Introduction: Patients with Parkinson’s disease (PD) show abnormal functional connectivity in large-scale brain networks. We explored resting state connectivity among the main networks, including the default mode network (DMN), dorsal attentional network (DAN), frontoparietal control network (FPCN) and visual network (VN) in PD patients with and without cognitive impairment (PD-MCI and PD-NC). Methods: 51 healthy controls (HC), 17 PD-NC and 24 PD-MCI were enrolled. Participants underwent cognitive testing and MRI examination at the baseline and at one year follow-up. Resting-state fMRI data were analysed and the inter-network connectivity was calculated between the FPCN and other networks. Spearman correlations with attention and executive domain z-scores were calculated. Results: FPCN-DAN, FPCN-VN and FPCN-DMN connectivities were significantly reduced in PD-NC as compared to HC. The connectivities decreased in the order HC > PD-MCI > PD-NC. At one-year follow-up, significant increases in FPCN-VN and FPCN-DMN connectivities were observed in the merged PD group, while no changes were detectable in the HC group. Conclusion: Decreased connectivity between the FPCN and other networks was observed already in PD-NC. PD-MCI tend to compensate for their cognitive deficit by increasing between-network connectivities. Moreover, the between-network connectivities were increased at the follow-up in the PD-all group, while no changes were found in HC. Acknowledgement: Supported by the EU Joint Programming initiative within Neurodegenerative Diseases, funded by the Norwegian Strategic Research Council (APGeM—Preclinical genotype-phenotype predictors of Alzheimer’s disease and other dementias, grant agreement number 3056-00001). We acknowledge also the core facility MAFIL of CEITEC supported by the MEYS CR (LM2015062 Czech-BioImaging). doi:10.1016/j.clinph.2018.01.032

13-PARAFAC decomposition of evoked potentials in patients treated by STN DBS—M. Lamoš, R. Marecˇek, M. Bocˇková, I. Rektor (CEITEC MU, Brno, Czech Republic) The effect of STN DBS (Deep Brain Stimulation of Subthalamic Nucleus) on the somatomotor network may differ from the effects on the cognitive networks (Rektor et al., 2015). Thus, we acquired high-density (HD) scalp EEG data from 10 Parkinson’s disease patients with STN DBS during DBS ON and OFF state while performing 3-stimulus visual oddball task and we employed blind 3-way decomposition method called PARAFAC. We performed PARAFAC on 3-way data array (Mørup et al., 2008) composed by preprocessed averaged trials from all patients, both states (DBS ON/OFF) and all stimulus types. The resulting estimated PARAFAC components have 3 signatures - topography, time series and trial strength loadings for particular averaged trials. Finally, we compared loadings between trial types during both states by Wilcoxon test. PARAFAC revealed evoked activity which showed significant difference between loadings of frequent and target stimuli in the DBS ON state and no difference in DBS OFF. We transformed the topography of the component into the source space, which points to areas of the fronto-parietal attention network.

PARAFAC decomposition of evoked potentials seems to be a helpful exploratory tool for HD EEG data. Our results also support a hypothesis that the DBS improves not only motor control but also affects cognitive networks. Acknowledgement: The research was supported by AZV grant 1633798A and by CF MAFIL of CEITEC (supported by the CzechBI large RI project LM2015062, MEYS CR). References Rektor Ivan et al. The modulatory role of subthalamic nucleus in cognitive functions–a viewpoint. Clin Neurophysiol 2015;126(4):653–8. Mørup Morten et al. Shift-invariant multilinear decomposition of neuroimaging data. NeuroImage 2008;42(4):1439–50. doi:10.1016/j.clinph.2018.01.033

14-Cognitive evoked potentials—M. Bareš (Department Neurology Faculty of Medicine, Brno, Czech Republic)

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Of particular interest in the cognitive neurophysiology are cognitive, or the event-related potentials (ERPs): Contingent Negative Variation (CNV), wave P300 or P3, Mismatch Negativity (MMN) and Bereitschaftspotential (BP) which are identified as slow cognitive potentials. P3 is elicited in the process of decision making; it is considered to be an endogenous potential (Sutton et al., 1965). CNV is a negative voltage change occurring between paired stimuli, when the first stimulus is a warning and the second stimulus requires a motor response or a decision (Walter et al., 1964). BP precedes self-paced voluntary movement in humans (Kornhuber and Deecke, 1965). An infrequent change in an otherwise repetitive acoustic stimulus leads to the genesis of MMN (Näätänen et al., 1978). The author provides the overview about the cognitive evoked potentials. References Kornhuber HH, Deecke L. Hirnpotentialanderungen bei Willkurbewegungen und passiven Bewegungen den Menschen: Bereitschaftspotential und reafferente Potentiale. Pflugers Arch 1965;284:1–17. Näätänen R, Gaillard AW, Mäntysalo S. Early selective-attention effect on evoked potential reinterpreted. Acta Psychol (Amst) 1978;42:313–29. Sutton S et al. Evoked-potential correlates of stimulus uncertainty. Science 1965;150 ():1187–8. Walter WG et al. The contingent negative variation: an electro-cortical sign of sensorimotor association in man. Electroenceph Clin Neurophysiol 1964 ():340–1. doi:10.1016/j.clinph.2018.01.034

15-Sensory and cognitive processing of visual stimuli in adolescents with type 1 diabetes mellitus: Electrophysiological study— J. Kremlácˇek 1, T. Vitvarová 2, D. Neumann 2 (1 Charles University, Faculty of Medicine in Hradec Králové, Czech Republic, 2 University Hospital Hradec Králové, Czech Republic) To quantify objectively visual processing and executive functions in adolescents with type 1 diabetes mellitus (T1D) we evaluated electrophysiological markers of brain response in the oddball task (P3b component) and to the pattern-reversal stimulation (P100 wave). While P100 wave indicates, with a millisecond accuracy, visual sensory processing, the P3b reflects key elements of the executive control like an attention, a short-term visual working memory, and a decision-making.

Abstracts / Clinical Neurophysiology 129 (2018) e7–e13

The peak time of the P100 wave in adolescents with T1D and without diabetic retinopathy (10 males, 12 females, 12–18 years) was significantly prolonged compared to a group of controls (8 males, 11 females, 10–21 years) p < 0.012, the P100 amplitudes did not differ (p > 0.066). In spite that peak time and amplitude of the P3b component did not diverge significantly, we found an enlarged area under curve of the P3b for patients (p = 0.035). There were no differences for the visual acuity, reaction time or task accuracy. Our study did show differences between groups in electrophysiological responses, in spite of no differences in their behavioral performance. Supported by MH CZ - DRO (UHHK). J. K. was supported by the Charles University project POGRES Q40/07. doi:10.1016/j.clinph.2018.01.035

16-Investigating modularity and its capacity as a marker of neurodegenerative diseases—E. Vy´tvarová 1,2, J. Fousek 1, M. Mikl 2, I. Rektorová 2 (1 Faculty of Informatics, Masaryk University, Brno, Czech Republic , 2 CEITEC, Masaryk University, Brno, Czech Republic) Early-stage detection of different kinds of dementia and cognitive impairments is an extremely important task. The neuroscience community is devoting great effort into finding potential markers of disease that would be noninvasive, easy to establish, and stable. In this paper, we evaluate different community detection algorithms and their strengths to discriminate between health and Parkinson’s disease (PD) and mild cognitive impairment preceding Alzheimer’s disease (AD-MCI). On a dataset of 50 controls (34 women; 66.74 ± 7.35 years) and 70 patients (35 women; 66.71 ± 9.44 years), the resting-state fMRI was measured. The data were preprocessed by 16 different variants of preprocessing, functional network for each subject and each preprocessing variant constructed and evaluated by diverse algorithms for modularity computation. The modularity coefficients reflect the ability of a network to form clusters. They were used as a classifier. We measured an increased modularity coefficient with 81.8% accuracy of classifying PD versus controls and 76.2% accuracy of classifying AD-MCI versus controls. Significantly higher modularity coefficient values were measured when the random matrix theory decomposition was adapted for network construction. These results were observed on networks of 82 nodes based on AAL atlas and 317 nodes based on multimodal parcellation atlas. doi:10.1016/j.clinph.2018.01.036

17-Neurological disorders in critically ill patients: Why to diagnose them?—J. Bednarˇík (Department of Neurology, University Hospital Brno, Czech Republic) The care of critically ill patients is quite problematic. One of the challenges is to find a proportion of diagnostic procedures aimed at newly defined neurological and neuromuscular disorders as a consequence of critical illness in order to optimize treatment and prognosis of these patients and at the same time to avoid needless stress and threat to them and to decrease the cost of care. Development of both critical illness polyneuropathy and myopathy, and critical illness encephalopathy worsen prognosis of critically ill patients. There are, however, only limited number of effective preventive or therapeutic measures available and therefore, especially invasive (muscle biopsy) or semi-invasive (EMG) diagnostic procedures without clear impact upon practical management of critically ill patients

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should be carefully considered. The importance of these procedures could, however, increase dramatically in case of discovery of effective prevention or therapy of these neurological disorders. Intensive research in this field is needed to improve this so far unsatisfactory situation despite challenging requirements for ethical attitude towards subjects participating in the research. doi:10.1016/j.clinph.2018.01.037

18-Hereditary sensory-motor neuropathy CMT 1C caused by a novel mutation in LITAF gene overlapped with an immune mediated asymmetric chronic inflammatory neuropathy (MADSAM)—M. Turcˇanová Koprušáková 1, M. Grofik 1, P. Jungová 2, J. Chandoga 2, E. Kurcˇa 1 (1 Clinic of Neurology, JLF UK Martin, Slovakia , 2 Department of Clinical Biology and Genetics, LF UK Bratislava, Slovakia) We report a family with a novel missense mutation in a LITAF gene (c348G > C p.Trp116Cys). One of the family members had a rapid stepwise deterioration of symptoms (subacute onset demyelinating asymmetric neuropathy of upper limbs ) in his 52 years. In patients with such kind of a rare mutation subacute or step progression can appear. Electrophysiological investigation can show temporal dispersion and conduction blocks – which is not typical feature in hereditary neuropathies, but was described in some rare mutations and also immune mediated neuropathies. Investigation of CSF, nerve conduction studies, MRI of brachial plexi were not significant for immune mediated neuropathy. We used calculated electrophysiological parameters - modified F ratio (MFR) and terminal latency index (TLI). These parameters were normal in mother and son who had the same mutation in LITAF gene, objectively confirmed moderate symmetric demyelinating polyneuropathy with conduction blocs, but they were without subjective difficulties. They were changed in our patient – before treatment (TLI was a little bit reduced 0.248 and MFR was prolonged 3.21) After 6 months of treatment with IVIG - paresthesias disappeared, weakness of upper limbs was reduced, minimal F wave latency was getting shorter, TLI (0, 3) and MFR (1, 8) returned to normal values. doi:10.1016/j.clinph.2018.01.038

19-Polio-like syndrome – Electrophysiological findings—E. Ehler (Neurological Department, Pardubice University, Czech Republic) Background: Although viral poliomyelitis has been eradicated in the Czech Republic for over 50 years, lesions of peripheral mononeurons with acute onset, frequently accompanied by fever, have still been known to occur. Despite the fact that there are no sensory distrubances, and the paresis tend to have typical distribution, they are often accompanied by pain. In addition, muscle atrophy is a regular occurence. These acute motoneuron disorders and their possible combination with motor roots disorder are called ‘‘polio-like syndromes.” Patients: Our group of patients consisted of 3 men and 1 woman with ages of 22, 38, 43 and 48 years. An infection resulting from tick meningoencephalitis was proven in 3 patients. All 4 patients had a febrile infection with meningeal syndrome, accompanied by the quick development of muscle weakness and atrophy, without sensory disturbances. Electrophysiological investigations: Motor conduction studies in the affected segments were characterized by low compound muscle potential. In F-wave studies we often found a prolongation of minimal F-wave latency, bigger signal dispersion and decreased stability. During a needle EMG investigation robust findings of fibrillations