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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[Objective - There is no internationally accepted guideline for treatment of spondylolisthesis in the literature, otherwise this degenerative disease has great social and economical impact. There is no hungarian study examining the efficacy of instrumented fusion procedure in surgical treatment of spondylolisthesis. In current study we examined the effectiveness of fusion technique focusing on the impact of quality of life. Methods - Between 1st January, 2011 and 30th June, 2012 we examined a group of patients - who were operated on by instrumented fusion technique because of spondylolisthesis -, in the National Institute of Clinical Neurosciences, using the Oswestry Low Back Disability Questionnaire. All patients were treated after ineffective conservative treatment. The question was wheather how has changed the patients’ quality of life after the operation. Paired-sample t-test was used in this study. Results - Eighty-eight of the 97 examined patients reported different levels of impovement in the postoperative period, two patient’s condition has not changed in spite of the surgery, seven patient’s condition showed progression in average one year after the surgery. The pain improved most significantly (55.5%) (p<0.0001). Using the 16 point borderline according to the Questionnaire (over moderate disability), significant improvement was detected in 50 patients (51.5%). Succesful surgical result - according to the quality of life - was seen in 77.41% of male and in 50.98% of female patients. According to the different age groups, 72.72% of the younger (before retirement), and 53.06% of the retired patients belonged to this group. At least 15 point improvement was detected 35.05% of the patients, the overall improvement was 10.5 point. Discussion - Our results proved effectiveness of instrumented surgical fusion procedure in the treatment of degenerative spondylolisthesis. According to our results the younger male population with significant symptoms is the group, where improvement in quality of life is more pronaunced after the surgical procedure. Conclusion - The instrumented fusion surgical technique provides successful clinical and surgical outcome in patients with degenerative spondylolisthesis. It could improve the quality of life. Althought multicentre follow-up studies are needed to determine the exact indication and optimal therapy.]

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