Clinical Neuroscience

[Analysis of mental arithmetic task by the “minimum spanning tree” method]

BOHA Roland1,2, TÓTH Brigitta1,2, KARDOS Zsófia3,2, FILE Bálint4, GAÁL Zsófia Anna2, MOLNÁR Márk5,2

MAY 30, 2016

Clinical Neuroscience - 2016;69(05-06)

DOI: https://doi.org/10.18071/isz.69.0169

[Goals - In the present study basic arithmetic induced rearrangements in functional connections of the brain were investigated by using graph theoretical analysis what becomes increasingly important both in theoretical neuroscience and also in clinical investigations. Research questions - During mental arithmetic operations (working) memory plays an important role, but there are only a few studies in which an attempt was made to separate this effect from the process of arithmetic operations themselves. The goal of our study was to separate the neural networks involved in cognitive functions. Methods - As an attempt to clarify this issue the graph-theoretical “minimal spanning tree” method was used for the analysis of EEG recorded during task performance. The effects of passive viewing, number recognition and mental arithmetic on PLI based minimal spanning trees (MST) were investigated on the EEG in young adults (adding task: 17 subjects; passive viewing and number recognition: 16 subjects) in the θ (4-8 Hz) frequency band. Results - Occipital task relevant synchronization was found by using the different methods, probably related to the effect of visual stimulation. With respect to diameter, eccentricity and fraction of leafs different task-related changes were found. Discussion - It was shown that the task related changes of various graph indices are capable to identify networks behind the various relevant dominant functions. Thus the “minimal spanning tree” method is suitable for the analysis of the reorganization of the brain with respect to cognitive functions.]

AFFILIATIONS

  1. ELTE, PPK, Pszichológiai Doktori Iskola, Budapest
  2. MTA, Természettudományi Kutatóközpont, Kognitív Idegtudományi és Pszichológiai Intézet, Budapest
  3. BME, Kognitív Tudományi Tanszék, Budapest
  4. PPKE, Információs Technológiai Kar, Budapest
  5. ELTE, PPK, Pszichológiai Intézet, Budapest

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[Background and purpose - Data on the disease burden of Duchenne Muscular Dystrophy are scarce in Hungary. The aim of this study was to assess patients’ and their caregivers’ health related quality of life and healthcare utilisations. Methods - A cross sectional survey was performed as part of the European BURQOL-RD project. The EQ-5D-5L and Barthel Index questionnaires were applied, health care utilisations and patients’ informal carers were surveyed. Results - One symptomatic female carer, 50 children (boys 94%) and six adult patients (five males) participated in the study, the latter two subgroups were included in the analysis. The average age was 9.7 (SD=4.6) and 24.3 (SD=9.8) years, respectively. Median age at time of diagnosis was three years. The average EQ-5D score among children and adults was 0.198 (SD=0.417) and 0.244 (SD=0.322), respectively, the Barthel Index was 57.6 (SD=29.9) and 53.0 (SD=36.5). Score of satisfaction with healthcare (10-point Likert-scale) was mean 5.3 (SD=2.1) and 5.3 (SD=2.9). 15 children were hospitalised in the past 12 months for mean 12.9 (SD=24.5) days. Two patients received help from professional carer. 25 children (mean age 11.1, SD=4.4 years) were helped/supervisied by principal informal carer (parent) for mean 90.1 (SD=44.4) hours/week and further family members helped in 21 cases. Correlation between EQ-5D and Barthel Index was strong and significant (0.731; p<0.01) as well as with informal care time (-0.770; p<0.01), but correlation with satisfaction with health care was not significant (EQ-5D: 0.241; Barthel Index: 0.219; informal care: -0.142). Conclusion - Duchenne muscular dystrophy leads to a significant deterioration in the quality of life of patients. Parents play outstanding role in the care of affected children. This study is the first in the Central and Eastern European region that provides quality of life data in this rare disease for further health economic studies.]

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[The rare, genetically determined group of diseases characterized by pathological accumulation of iron in the central nervous system and progressive, typically movement disorder’s symptoms are called NBIA (neurodegeneration with brain iron accumulation). By the rapid development of molecular genetics, it has become apparent that different mutations in numerous genes can lead to pathological cerebral iron accumulation. Simultaneously, it has also been recognized that the age of onset, the symptoms and the prognosis of NBIA disorders are much more diverse than it was previously perceived. To our knowledge, a review article on the most recent clinical data of NBIA has not been published in Hungarian. In the first part of this publication, we survey the general clinical characteristics and the diagnostic algorithm of NBIA diseases and address some considerations for differential diagnostics. In the second part of this review, the particular NBIA disorders are presented in details. The purpose of this article is to provide a clinical overview that may be useful for neurologists, pediatricians and any other medical practitioners interested in this field.]

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