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Predicting postural control adaptation measuring EEG, EMG, and center of pressure changes : BioVRSea paradigm
(2022-12-15) Stehle, Simon A.; Aubonnet, Romain; Hassan, Mahmoud; Recenti, Marco; Jacob, Deborah Cecelia Rose; Petersen, Hannes; Gargiulo, Paolo; Faculty of Medicine
Introduction: Postural control is a sensorimotor mechanism that can reveal neurophysiological disorder. The present work studies the quantitative response to a complex postural control task. Methods: We measure electroencephalography (EEG), electromyography (EMG), and center of pressure (CoP) signals during a virtual reality (VR) experience called BioVRSea with the aim of classifying different postural control responses. The BioVRSea paradigm is based on six different phases where motion and visual stimulation are modulated throughout the experiment, inducing subjects to a different adaptive postural control strategy. The goal of the study is to assess the predictability of those responses. During the experiment, brain activity was recorded from a 64-channel EEG, muscle activity was determined with six wireless EMG sensors placed on lower leg muscles, and individual movement measured by the CoP. One-hundred and seventy-two healthy individuals underwent the BioVRSea paradigm and 318 features were extracted from each phase of the experiment. Machine learning techniques were employed to: (1) classify the phases of the experiment; (2) assess the most notable features; and (3) identify a quantitative pattern for healthy responses. Results: The results show that the EEG features are not sufficient to predict the distinct phases of the experiment, but they can distinguish visual and motion onset stimulation. EMG features and CoP features, when used jointly, can predict five out of six phases with a mean accuracy of 74.4% (±8%) and an AUC of 0.92. The most important feature to identify the different adaptive strategies is the Squared Root Mean Distance of points on Medio-Lateral axis (RDIST_ML). Discussion: This work shows the importance and the feasibility of a quantitative evaluation in a complex postural control task and demonstrates the potential of EEG, CoP, and EMG for assessing pathological conditions. These predictive systems pave the way for developing an objective assessment of pathological behavior PC responses. This will be a first step in identifying individual disorders and treatment options.
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Motion sickness susceptibility and visually induced motion sickness as diagnostic signs in Parkinson's disease
(2022-12-16) Petel, Arthur; Jacob, Deborah Cecelia Rose; Aubonnet, Romain; Frismand, Solène; Petersen, Hannes; Gargiulo, Paolo; Perrin, Philippe; Faculty of Medicine
Postural instability and loss of vestibular and somatosensory acuity are among the signs encountered in Parkinson's disease (PD). Visual dependency is described in PD. These modifications of sensory input hierarchy are predictors of motion sickness (MS). The aim of this study was to assess MS susceptibility and the effects of real induced MS in posture. Sixty-three PD patients, whose medication levels (levodopa) reflected the severity of the pathology were evaluated, and 27 healthy controls, filled a MS questionnaire; 11 PD patients and 41 healthy controls were assessed by posturography using virtual reality. The levels of levodopa predicted visual MS (p=0.01), but not real induced MS susceptibility. PD patients did not experience postural instability in virtual reality, contrary to healthy controls. Since PD patients do not seem to feel vestibular stimulated MS, they may not rely on vestibular and somatosensory inputs during the stimulation. However, they feel visually induced MS more with higher levels of levodopa. Levodopa amount can increase visual dependency for postural control. The strongest MS predictors must be studied in PD to better understand the effect of visual stimulation and its absence in vestibular stimulation.
Verk
Skuldbinding leikskólakennara til vinnustaðar: Starfsandi í lykilhlutverki
(2023-02-20) Isaksen, Rakel Ýr; Ástvaldsdóttir, Ingileif; Stefánsson, Kristján Ketill; Deild kennslu- og menntunarfræði; Menntavísindasvið
Lög um eitt leyfisbréf leik-, grunn- og framhaldsskólakennara tóku gildi þann 1. janúar 2020. Eftir gildistöku laganna flutti fjöldi leikskólakennara sig um set og hóf störf á grunnskólastigi. Markmið rannsóknarinnar var að bæta stöðu þekkingar og koma auga á vísbendingar um hvernig megi varðveita hæfni og sérþekkingu starfandi leikskólakennara. Rannsóknaraðferðin var megindleg, rýnt var í fyrirliggjandi gögn og þau greind með lýsandi tölfræði og fjölbreytuaðhvarfsgreiningu. Gagnasafnið samanstóð af svörum 1250 leikskólakennara við starfsmannakönnun Skólapúlsins fyrir leikskóla, sem svarað var vorin 2020 og 2021. Tvíþáttakenningin (e. Motivation hygiene theory) var lögð til grundvallar varðandi greiningu gagnanna. Tvær tilgátur voru prófaðar: 1. Leikskólakennarar sem upplifa sterka hvataþætti (t.d. góðan starfsanda) eru líklegir til að sýna skuldbindingu til vinnustaðar; 2. Leikskólakennarar sem upplifa slaka hollustuhætti (t.d. mikið vinnuálag) eru ólíklegir til að sýna skuldbindingu til vinnustaðar. Niðurstöður rannsóknarinnar bentu til að hvataþættirnir starfsandi, jákvæðar áskoranir í starfi og ræktun mannauðs væru í lykilhlutverki hvað varðar skuldbindingu leikskólakennara til vinnustaðarins. Niðurstöðurnar gáfu jafnframt til kynna að viðvarandi vinnuálag spilaði mikilvægt hlutverk í ótímabæru brotthvarfi leikskólakennara úr starfi. Brýnt virðist að styðja við hvatabundna þætti og draga úr neikvæðum hollustuþáttum í starfsumhverfi leikskóla.
Verk
A repeated cross-sectional analysis of the Icelandic baby food market surveyed in 2016, 2019 and 2021
(2024-01) Thorisdottir, Birna; Odinsdottir, Tinna; Thorsdottir, Inga; Faculty of Food Science and Nutrition; Health Sciences
World Health Organisation (WHO) has stated that countries need to know their local commercial baby food (CBF) market. Data from other countries suggest rapid changes in CBF options, highlighting the need for repeated analysis. In that context, this repeated cross-sectional study analysed the options and nutrient quality of different CBF types available in Iceland in years 2016, 2019 and 2021. Data was gathered on formulas, porridge flours, foods in jars and pouches, finger-foods, other CBF. They were classified into 26 subgroups based on ingredients and taste (sweet/savoury). Minimum consumer age as suggested by the manufacturers and nutritional content were registered. In each data-collection, 250–275 products were available. Over a third of products (37%–44%) were in pouches. Availability of products intended for 4–11-month-old infants decreased, driven largely by a 65% decrease in availability of food in jars (sweet/savoury) between 2016 and 2021. Availability of products intended from 12+ months or without age-labels increased, driven largely by quadrupling of finger-foods (predominantly sweet) between 2016 and 2021. The overall percentage of products classified as sweet increased from 65% (2016) to 73% (2019) and 77% (2021). Some finger-foods had high sugar content (up to 72 g/100 g), partly from fruit concentrate or sugar/syrup. Like other countries, the Icelandic CBF market has moved towards less availability of food intended in the first year and more availability of sweet finger-foods for an expanded consumer age. As sugar is added to some CBF, stronger regulations on promotion of foods for young consumers and updated recommendations for parents/caregivers may be needed.
Verk
Nýgengi, orsök og meðferð bráðs rofs á ristli á Íslandi 1998-2007
(2017-02-03) Valsdóttir, Elsa Björk; Jónsdóttir, Kristín; Datye, Shreekrishna; Berndsen, Fritz; Möller, Páll Helgi
Inngangur: Rof á ristli er alvarlegt sjúkdómsástand með háa dánartíðni. Áður fyrr var meðferðin fyrst og fremst skurðaðgerð en á undanförnum árum hafa rannsóknir sýnt sambærilegan árangur með stuðningsmeðferð. Tilgangur þessarar rannsóknar var að skoða nýgengi, orsakir, meðferð og afdrif sjúklinga með brátt rof á ristli á Íslandi á tímabilinu 1998-2007. Efniviður og aðferðir: Gerð var afturskyggn leit í sjúkraskrám Landspítala, Sjúkrahússins á Akureyri og Heilbrigðisstofnunar Vesturlands á Akranesi að líklegum greiningarkóðum miðað við greiningarkerfi Alþjóðaheilbrigðisstofnunarinnar. Safnað var gögnum um kyn, aldur, greiningarár, orsakir, greiningu, meðferð og afdrif einstaklinga með brátt rof á ristli. Niðurstöður: 225 sjúklingar uppfylltu skilyrði rannsóknarinnar, 131 kona (58%) og 94 karlar (42%). Miðgildi aldurs var 70 ár (bil 30-95 ár). Algengustu ástæður rofs voru sarpabólga (67%), áverki við ristilspeglun (12%) og fylgikvillar aðgerða. Á fyrri 5 árum rannsóknartímabilsins fengu 27% sjúklinganna meðferð án aðgerðar en 71% fór í aðgerð. Á seinni 5 árunum var hlutfallið 45% og 54%. Um 24% sjúklinganna fengu varanlegt stóma. Tæpur helmingur sjúklinga, eða 101 (46%), fékk 140 fylgikvilla og var skurðsárasýking þar algengust. Þrjátíu daga dánartíðni var 11% en eins árs dánartíðni 20%. Ályktun: Sarpabólga var algengasta orsök rofs á ristli á Íslandi á rannsóknartímabilinu. Á sama tímabili jókst notkun stuðningsmeðferðar á meðan skurðaðgerðum fækkaði. Hlutfall þeirra sjúklinga sem fengu stóma og fóru síðar í aðgerð þar sem gerð var endurtenging er hátt hérlendis og fyllilega sambærilegt því sem lýst er í erlendum rannsóknum. Introduction: Colon perforation is a serious illness with mortality reported from 0-39%. Surgery used to be the gold standard but treatment has changed as studies have indicated comparable results with less invasive treatment. The aim of this study was to evaluate the incidence of acute colon perforations in Iceland, causes and treatment. Material and methods: A retrospective, nationwide, multicenter analysis was performed based on ICD-10 codes from databases of the main hospitals in Iceland. Age, gender, year of perforation, cause, means of diagnosis, treatment and outcome were registered. Patients under 18 years and post mortem diagnosis were excluded. Results: 225 patients met criteria, 131 women (58%) and 94 men (42%), median age 70 years (range 30-95). The most common causes were diverticulitis (67%), colonoscopy (12%) and complications during operations (5%). During the first five study years, 27% received conservative treatment while 71% underwent surgery. By the end of the study era this ratio was 45% and 54% respectively. The rate of permanent stoma was 10%. Conclusions: Diverticulitis was the most common cause of colon perforation in Iceland during the study period. Many patients still undergo surgery but there has been a dramatic change toward more conservative treatment. The rate of stoma closure is comparable to studies elsewhere.