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Developing Brain Computer Interface for Imagined Movements
Blašková, Barbora ; Jawed, Soyiba (referee) ; Malik, Aamir Saeed (advisor)
Rôzne poruchy a choroby mozgu postihujú približne každého šiesteho človeka a veľa z nich necháva na pacientoch trvalé následky. Téma mentálneho zdravia je čoraz viac dôležitá, keďže každý desiaty človek má diagnostikovanú mentálnu poruchu. Je preto dôležité študovať orgán, ktorý je stále z veľkej čati záhadou - mozog. Diplomová práca sa zameriava na Brain Computer Interface (BCI) - rozhranie, ktoré ponúka priame komunikačné spojenie medzi mozgom a vonkajším svetom. Základná myšlienka BCI je veľmi jednoduchá - najprv získať signál z mozgu, dekódovať ho a vykonať akciu vychádzajúcu zo zámeru užívateľa. Jedna z metód ako pomocou mozgu priamo komunikovať sú predstavované pohyby, čo je metóda založená na fakte, že predstava pohybu vyvoláva v mozgu rovnakú odozvu ako skutočný pohyb. V diplomovej práci je navrhnuté použiť EEG a jeho relatívne novú metódu analýzy - mikrostavy. Klasifikátor na rozlišovanie medzi úlohami predstavovaných pohybov je navrhnutý ako kombinácia vlastností mikrostavov extrahovaných z rôznych oblastí mozgu s už známymi vlastnosťami, ako napríklad frekvenčné alebo časové vlastnosti signálu. Klasifikátory boli natrénované na 30 účastníkoch, pre každého zvlášť.Boli implementované dva odlišné klasifikátory - jeden na klasifikáciu nečinnosti oproti aktivite a druhý na klasifikáciu predstavy pohybu ľavej ruky verzus pravej ruky. Priemerná presnosť klasifikácie nečinnosti a aktivity bola 0.85. Priemerná presnosť klasifikácie predstavy pohybu ľavej a pravej ruky bola 0.74. Ukázalo sa, že mikrostavy sú užitočné pri rozlišovaní medzi rôznymi stavmi v kontexte predstavovaných pohybov a BCI, ale potrebujú určité vylepšenia z hľadiska ďalšieho výskumu.
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Brain Source Activity Changes During the Visual Training of the Imagination Viewed by sLORETA Imaging
Englerová, Barbora ; Pánek, David (advisor) ; Pavlů, Dagmar (referee)
Title: Brain Source Activity Changes During the Visual Training of the Imagination Viewed by sLORETA Imaging. Objectives: The research study aims to determine which changes in brain source activity occur before and after an intervention in the form of a three-week visual training of motor imagery. The electrical activity of the brain was recorded using scalp EEG and transferred to the sLORETA program, in which the source brain activity was evaluated. Methods: The research was concluded on 13 healthy subjects aged between 20-30 years. The Czech standardized version of The Vividness of Movement Imagery Questionnaire - 2 (VMIQ - 2) was used for the survey. The electrical activity of the brain was recorded using a scalp EEG Nicolet TM EEG Wireless Amplifier 32/64 by Natus Neurology. The research consisted of initial and control measurements, the measurement included several phases. First, an initial measurement took place, which always included measurements of resting EEG (5minutes eyes open and 5 minutes eyes closed), action observation in VR (3 minutes) and subsequent measurement of the motor imagery with eyes open (3 minutes). Between the individual measurements, there was a three-week visual training of motor imagery, which included action observation in VR and the individual motor imagery three...
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Assessment of Independent EEG Components Obtained by Different Methods for BCI Based on Motor Imagery
Húsek, Dušan ; Frolov, A. A. ; Kerechanin, J. V. ; Bobrov, P.D.
Eight methods of decomposition of a multichannel EEG signal are compared in terms of their ability to identify the most physiologically significant components. The criterion for the meaningfulness of a method is its ability to reduce mutual information between components; to create components that can be attributed to the activity of dipoles located in the cerebral cortex; find components that are provided by other methods and for this case; and at the same time, these components should most contribute to the accuracy of the BCI based on imaginary movement. Independent component analysis methods AMICA, RUNICA and FASTICA outperform others in the first three criteria and are second only to the Common Spatial Patterns method in the fourth criterion. The components created by all methods for 386 experimental sessions of 27 subjects were combined into more than 100 clusters containing more than 10 elements. Additionally, the components of the 12 largest clusters were analyzed. They have proven to be of great importance in controlling BCI, their origins can be modeled using dipoles in the brain, and they have been detected by several degradation methods. Five of the 12 selected components have been identified and described in our previous articles. Even if the physiological and functional origins of the rest of identified components’ are to be the subject of further research, we have shown that their physiological nature is at least highly probable.\n
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The Influence of Virtual Reality on Psychosomatic State of Patients with Spinal Cord Injury
Nosková, Kateřina ; Pánek, David (advisor) ; Maršáková, Kateřina (referee)
The Aim of the Study: The aim of this diploma thesis is to capture the change of clinical state of patients with spinal cord injury while watching videos of virtual reality fot three 3 months using ASIA assessment. The goal is to determine the effect of the change of clinical state on the patient's quality of life while using SQUALA and on their imagery ability (WIAQ) while a therapeutic video of virtual reality is regularly played through virtual reality headset. Methods: The research was conducted with 7 probands (n=7, 5 males, 2 females) aged between 31 and 61 years (the average age of 49,6 years), which regular visitors of Centrum Paraple, o. p. s. The propands who participated in research suffer with incomplete spinal lesion. Before any intervention the probands were assessed by ASIA, standardised assessment to estimate neurological level of spinal lesion by assigning the number of motor and sensitive points in each segment. The assessment was conducted by proffessional and specificly trained staff of Centrum Paraple, o. p. s. Furthermore the probands completed the psychological questionnaires to evaluate their quality of life (SQUALA) and imagery ability of the movement (WIAQ) in the pacient with spinal cord injury. As in the beginnig, so in the end of the research the ASIA was conducted once...
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