Clinical Neuroscience

[Péter Halász, Róbert Bódizs: Dynamic structure of NREM sleep]

BORBÉLY Alexander

MAY 30, 2013

Clinical Neuroscience - 2013;66(05-06)



Further articles in this publication

Clinical Neuroscience

[Continuous dopaminergic stimulation in Parkinson disease: possibilities in 2013]

ASCHERMANN Zsuzsanna, KOVÁCS Norbert, KOMOLY Sámuel

Clinical Neuroscience

[Spectral, phase-synchronization, and graph theoretical EEG changes related to mental arithmetics]

BOHA Roland, TÓTH Brigitta, GAÁL Zsófia Anna, KARDOS Zsófia, FILE Bálint, MOLNÁR Márk

[During mental arithmetic operations working memory playsan important role, but there are only few studies in which anattempt was made to separate this effect from the process ofarithmetics per se. In this study the effects of arithmetic onthe EEG of young adults (14 participants, six of themwomen, mean age 21.57 years, SD: 2.62) was investigatedduring a subtraction task in the θ(4-8 Hz) frequency band.Besides the power density spectrum analysis phasesynchrony based on recently developed graph theoreticalmethods were used and strength of local connections (clustercoefficient; C) and global interconnectedness of network(characteristic path length; L) were determined. Before thearithmetic task passive viewing (control situation) and anumber recognition paradigms were used. During the arith-metic task compared to the control situation significantlyincreasing phase synchrony and C values were found. L wassignificantly shorter (F(2, 26)=818.77, p<0.0001) only dur-ing the arithmetic task: this fact and the former two resultsimply that the network topology shifted towards the “smallworld” direction. Our findings concerning regionaldifferences confirm those reported earlier in the literature:compared to the control condition significant task-relatedincrease was found in C values in the parietal areas [moreexplicitly in the left side, (F(1, 13)=7.2020, p=0.0188)],which probably corresponds to stronger local connectionsand more synchronized (sub)networks. During the task con-dition significantly increased θband power; (F(1,13)=7.9708, p=0.0144) and decreased L values werefound in the left frontal region compared to the right side(F(1, 13)=6.0734, p=0.0284), which can also be interpret-ed as an indicator of optimized network topology ofinformation processing.]

Clinical Neuroscience

[Identification of new biomarkers, translational studies]


Clinical Neuroscience

[Can somatosensory evoked potentials predict disease course in early multiple sclerosis patients?]

NAGY Helga, RAJDA Cecília, OROSZ Péter, BENCSIK Krisztina, BENEDEK Krisztina, KÉRI Szabolcs, VÉCSEI László, BENICZKY Sándor

[Background - Multiple sclerosis (MS) is an autoimmune degenerating disease, where myelin degradation as well as axonal loss is present. Purpose - To asses whether recording the middle-latency components of the median nerve somatosensory evoked potentials (SEPs) increases the diagnostic sensitivity in patients with MS, and to investigate whether any of the abnormalities correlates with the severity of the clinical signs and predicts future outcome. Methods - Twenty consecutive MS patients at early onset were included. Median and tibial nerve SEPs were recorded at the time of the referral. Extended Disability Status Scale (EDSS) and Multiple Sclerosis Severity Score (MSSS) were assessed at the time of the referral and after 5-year followup. Results - Recording the middle-latency components increased the sensitivity of the median nerve SEPs from 50% to 75%. The overall sensitivity of the SEPs (i.e. including also tibial nerve SEPs) modestly increased (from 80% to 90%). The amplitude of the cortical N20 potential of the median nerve was inversely correlated to the clinical severity. None of the parameters could predict the future outcome. Conclusions - Our results provide neurophysiological evidence for the role of axonal lesions in the clinical disability of the patients with MS.]

Clinical Neuroscience

[Congenital myasthenic syndromes and transient myasthenia gravis]

GAJDA Anna, SZABÓ Hajnalka, GERGEV Gyurgyinka, KARCAGI Veronika, SZABÓ Nóra, ENDREFFY Emőke, TÚRI Sándor, SZTRIHA László

[Hypotonia in the neonatal period and early infancy is a common clinical finding. It can be caused by various heterogeneous disorders of different origin which might lead to diagnostic difficulties. Disorders of the neuromuscular junction, such as congenital myasthenic syndromes and neonatal transient myasthenia gravis are among the aetiologies. We report on a case of congenital myasthenia caused by mutation in the long cytoplasmic loop of the epsilon subunit of the acetylcholine receptor and a neonate of a myasthenic mother diagnosed with transient myasthenia gravis.]

All articles in the issue

Related contents

Clinical Neuroscience

[The role of sleep in the relational memory processes ]

CSÁBI Eszter, ZÁMBÓ Ágnes, PROKECZ Lídia

[A growing body of evidence suggests that sleep plays an essential role in the consolidation of different memory systems, but less is known about the beneficial effect of sleep on relational memory processes and the recognition of emotional facial expressions, however, it is a fundamental cognitive skill in human everyday life. Thus, the study aims to investigate the effect of timing of learning and the role of sleep in relational memory processes. 84 young adults (average age: 22.36 (SD: 3.22), 21 male/63 female) participated in our study, divided into two groups: evening group and morning group indicating the time of learning. We used the face-name task to measure relational memory and facial expression recognition. There were two sessions for both groups: the immediate testing phase and the delayed retesting phase, separated by 24 hours. 84 young adults (average age: 22.36 (SD: 3.22), 21 male/63 female) participated in our study, divided into two groups: evening group and morning group indicating the time of learning. We used the face-name task to measure relational memory and facial expression recognition. There were two sessions for both groups: the immediate testing phase and the delayed retesting phase, separated by 24 hours. Our results suggest that the timing of learning and sleep plays an important role in the stabilizing process of memory representation to resist against forgetting.]

Clinical Neuroscience

Restless leg syndrome frequency in health workers

ÖCAL Ruhsen, ATGÜDEN Gizem, AYCAN Cagri, BALABAN Zeynep, SENAR Seran, YAVUZ Sena

Introduction - Restless Leg Syndrome (RLS) is a disease, primarily composed of sensational symptoms, caused by the urge to move lower extremities especially at night, and characterized by undesired feelings of the legs. Decreasing of the dopaminergic effect at night is thought to be responsible from these symptoms. RLS patients suffer from low quality of sleep affecting their daily life activities even causing socio-economic loss. Although RLS is a common and treatable disease, it can not be diagnosed easily due to the variability of symptoms. Aim - The purpose of this study is to determine the frequency of RLS among health workers and to define the disease causing factors. Method - A questionnaire was applied to 174 randomly selected health workers at Baskent University Medical Faculty (KA17/285). The demographic information, history of illnesses or usage of drugs, socioeconomic status, working hours and daytime sleepiness were questioned. Included in the questionnaire were diagnostic criteria for RLS, frequency assessment scale, and survey of sleep quality. We used “the diagnostic criteria of international RLS working group” for the diagnosis, and “Pittsburgh sleep quality index survey” to determine the quality of sleep. Reliability and validity studies were performed on both tests. Results - A significant relationship between socio-economic status and RLS was found (p<0.05) as an increase of RLS frequency in parallel with decreased socio-economic status. RLS was found to be common among health workers. We suggest that health workers should be checked regularly, and they should be informed about the disease in order to raise an awareness and hence increase their quality of life.


[New findings in the cortical bone biology and its role in bone fractures]


[The authors surveyed the already known factors responsible for the osteoporotic bone fragility. Then the results of using modern imaging techniques (micro-CT, high-resolution peripheral computed quantitative tomograph - HR-pQCT) and advanced computer analytic methods (finite element analysis, FEA) are presented. These data - beyond the already known fracture risk factors (age, risk of falling, bone mineral density - BMD, and fine structure damage of trabecular bone) are stressing the importance of the (micro)damage of cortical bone as a fracture risk factor, which has been still underrated. The cortical thickening and increased porosity - verified on various population samples - are increasing the risk of fractures in certain subgroups of subjects having identical BMD values, even among those, who are considered only osteopenic by the earlier classification based on BMD values. Backed with modern software batteries, the new imaging techniques are expected to enter clinical application in the near future. Pharmacologic agents with stronger cortical effect are already available and research is continuing to find new drugs to use in the management of osteoporotic patients of high fracture risk.]

Clinical Neuroscience

[Decisional collisions between evidence and experience based medicine in care of people with epilepsy]


[Background – Based on the literature and his long-term clinical practice the author stresses the main collisions of evidence and experience based medicine in the care of people with epilepsy. Purpose – To see, what are the professional decisions of high responsibility in the epilepsy-care, in whose the relevant clinical research is still lacking or does not give a satisfactory basis. Methods – Following the structure of the Hungarian Guideline the author points the critical situations and decisions. He explains also the causes of the dilemmas: the lack or uncertainty of evidences or the difficulty of scientific investigation of the situation. Results – There are some priorities of experience based medicine in the following areas: definition of epilepsy, classification of seizures, etiology – including genetic background –, role of precipitating and provoking factors. These are able to influence the complex diagnosis. In the pharmacotherapy the choice of the first drug and the optimal algorithm as well as the tasks during the care are also depends on personal experiences sometimes contradictory to the official recommendations. Same can occur in the choice of the non-pharmacological treatments and rehabilitation. Discussion and conclusion – Personal professional experiences (and interests of patients) must be obligatory accessories of evidence based attitude, but for achieving the optimal results, in some situations they replace the official recommendations. Therefore it is very important that the problematic patients do meet experts having necessary experiences and also professional responsibility to help in these decisions. ]

Clinical Neuroscience

[Effect of two month positive airway pressure therapy on the structure of sleep, cognitive function and anxiety]


[Obstructive sleep apnea is a common disorder, characterized by repeated episodes of upper airway obstruction during sleep, resulting intermittent hypoxia and disruption of the normal sleep pattern, which caused cognitive dysfunction in these patients. Nasal continuous positive airway pressure is the treatment of choice for this disorder. The aim of the study is to evaluate the effect of short-term positive airway pressure on sleep pattern (polisomnographic measures), cognitive function and anxiety. Twenty four newly diagnosed and previously untreated patients with obstructive sleep apnea were evaluated a battery of neuropsychological tests before and after 2 and a half months of the treatment. We focused on working memory, short and long-term episodic memory, executive functions, anxiety and subjective sleepiness. Our results showed that the two and half month of treatment improved the respiration during sleep, sleep pattern and the subjective sleepiness. We found improvement in short- and long-term verbal memory, and complex working memory. Despite of treatment we did not find improvement in visuospatial learning. These results reveal that 2 and a half months of positive airway pressure treatment restored not only the normal respiration during sleep and normal sleep pattern, but also the cognitive functions. Our study suggests that cognitive dysfunction is at least partial reversible in obstructive sleep apnea patients after positive airway pressure treatment.]