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Development of callosal interhemispheric connection in laboratory rat
Matternová, Lucie ; Mareš, Pavel (advisor) ; Žiak, Jakub (referee)
Corpus callosum is the main commissure linking cortex of the right and left brain hemisphere. For the first time, the callosal axons are observed during E18, when they cross the midline. In PND 5, most axons reach the contralateral cortex, and at the end of the second postnatal week, the callosal projection neurons and axon terminals are located similarly to the adult animal. The interhemispheric response was first observed in the rat in PND 4 but myelination in PND 12, suggesting that the transcallosal response is not dependent on myelinization of callosal fibers. As the rat age increases, the wave duration of the TCR, latency peak and threshold decreases. As opposed to that, amplitude of the positive and negative wave increases with age. TCR may be affected by acute drug application or chronic exposure to various effects, such as hormones.
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ROS and its role in neurophysiology
Šedivcová, Pavlína ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Name of the thesis Reactive oxygen species and their neurophysiological role Aim of the thesis Aim of the theoretical part is to provide overview of reactive oxygen species (ROS) and show their place in organism - posstive and necessary effects for the organism on the one hand and source of serious diseases on the other hand. Futhermore, the theoretical part deals with the restoration balance between the production of free radicals and antioxidants protection. Theoretical part also deals with substance FeTTPS. Aim of the experimental part is to determinate whether the application of FeTTPS affects cerebral blood flow during trancallosal stimulation with increasing frequency. Futhermore, to determinate whether the applicatication of this substance affects the slope of the curve and threshold of evoked potencials and number and duration of afterdischargers. Research method The research took place at the premises of Onstitue of Physiology, Academy of Sciences, Czech Republic. Experiments were carried out on laboratory albine Wistar rats. General anesthesia was performed to rats, stimulating and sensing electrodes were implated in epidural area of sensorimotoor cortex and Laser Doppler flow probe was implated into the contralateral hemisphere. In the first part of experiment included 11 animals. We...
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Neural correlates of emotional facial expressions perception
SLABÝ, Lukáš
This thesis deals with differences of perception of facial emotional expressions at the neural level. The theoretical part contains information about emotions, their basic theories and six basic emotional expressions. Furthermore, the theoretical part clarifies electroencephalography - the method of recording electrical activity of the brain and event-related potentials (ERP). The practical part is focused on the experiment, whose aim is to describe the differences in the event-realted potentials of perception of facial emotional expressions and neutral expression, to compare the event-related potentials of perception of positive and negative emotions and to compare event-related potentials of two databases of facial emotional expressions (WSEFEP, KDEF) which were used in this experiment. 13 subject participes in this experiment. The subjects were exposed to visual stimuli (facial emotional expressions) and the EEG signal were simultaneously recorded. This signal was further filtered and analyzed in Matlab and its EEGlab toolbox. A paired T-test and ANOVA were used for statistical data processing. Four hypotheses for this research were formed. The first hypothesis, which contended that the perception of facial emotional expressions would differ among each other in event-related potentials, was accepted. The second hypothesis, which claimed that there are differences in the event-related potentials of facial emotional expressions and neutral expressions, could not be accepted for lack of evidence. The third hypothesis, which asserted that there are differences in the event-related potentials of perception of positive and negative facial emotional expressions, was accepted. The fourth hypothesis, which asserted that there is a difference in the event-related potentials between the perception of facial emotional expressions from the WSEFEP database and the KDEF database, was accepted for sufficient evidence.
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Evoked potentials and its sensing
Fabianová, Katarína ; Janoušek, Oto (referee) ; Chmelař, Milan (advisor)
An electrical activity of the brain can be spontaneous (a signal is produced during the life of the individual) or can be evoked (a reply to the external above threshold stimulus). This work is largely dedicated to evoked potentials by which the brain reacts normal or abnormal to given external stimuli (sound, light, etc.). The main essence of this work is a project of the simple acoustical generator for the research of evoked potentials. This acoustical generator is also useable in connection with the EEG device from Alien Technic without any intervention to this device. Acoustical evoked potentials belong to the most widely used objective examinations of the sense of hearing.
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Ballistocardiogram artifact removal from EEG signal
Doležal, Vít ; Kolář, Radim (referee) ; Kolářová, Jana (advisor)
Diplomová práce se zabývá hybridním vyšetřením fMRI-EEG. V EEG signálu jsou přítomny dva základní artefakty, gradientní a balistokardiografický. Po odstranění gradientního artefaktu a detekce R vln v kanálu EKG byl navržen postup pro odstranění balistokardiografického artefaktu, pomocí metody odečtu artefaktového vzoru, pomocí metody ICA (metody nezávislých proměnných) a metody spojující obě uvedené. Byla vyhodnocena úspěšnost všech metod a jejich vliv na evokované potenciály v signálu EEG.
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Acoustic generator for evoked potentials stimulation
Škutková, Helena ; Rampl, Ivan (referee) ; Chmelař, Milan (advisor)
Evoked potentials are electric brain response to external stimulus. They are important diagnostic no visual method in neurology. For their excitation use of different of kinds stimulation, most often: visual, auditory, somatosenzory, olfactory and gustatory. Evoked potentials are objective method for measurement sense perception. This master’s thesis is specialized to auditory evoked potentials and design acoustic generator for their stimulation. Auditory evoked potentials are primary used for objective audiometry, but they have another usage. In the first place, application is specialized on health sector. The aim of this master’s thesis is compact specified medical requirements with available technical resources.
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EEG activity during emotional stimulation
HOROVÁ, Jana
The presented thesis deals with study of emotion and impact of emotional stimulation on Electroencephaography (EEG) signal. The aim of this statement is to determine if it is possible to detect different classes of emotionally charged words and to verify hypothesis, that there is a significant difference in event-related potential of emotional word to emotional content. The theoretical part is focused on the electrical activity of the brain over a period of time, the method of electroencephalography, event-related potentials (ERP), fundamental study of emotions, including stimulus material in regarding to examining of emotions and ERP of emotional response. There are also mapped factors correlating with the investigation of emotions. The practical part deals with the implementation of a the project examined using Experimental method where investigated ERP response to variously emotionally tinged and neutral words is. Research was attended by eleven undergraduate students, as the sampling method was used the method of snowballs. Data were processed and analyzed in EEGlab and then using of statistical analysis of variance method (ANOVA) and paired T-test evaluated.
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