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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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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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Numerosity in college students of math; event-related potential
VESELÝ, Denis
This bachelor thesis deal with design proposal of description of speed-accuracy tradeoff (SAT) influence, on approximal arithmetic tasks; at college math students. We focuses on description of neural correlates of number processing; measured through brain activity of performance at tasks mentioned above. Second interest of ours, aims for analysis of possible behavioral influence, arises in these tasks. Approximate number system (ANS) is one of theoretical neurocognitive systems, responsible for such processing. And thus, it creates basis for symbolic math understanding. As this, there is strong research interest for investigation of its functions. Nevertheless, it seems like there is just trifling number of works, which are focused on hypothetical SAT influence on collected evidence. Despite the fact, that SAT is rather important phenomenon in cognitive science. It describes individual's tendency, for trading reaction speed for reaction accuracy and vice versa. And so, this work pursue description of ANS and SAT, propose possibilities of testing both phenomena and also tries to illustrate theoretical future of researches of similar character.
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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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The Possibilities of Influencing the Neuropathic Pain via Virtual Reality in Incomplete Spinal Cord Injury Patients.
Hunčovský, Tomáš ; Pánek, David (advisor) ; Pavlů, Dagmar (referee)
Title: The Possibilities of Influencing the Neuropathic Pain via Virtual Reality in Incomplete Spinal Cord Injury Patients. Objectives: The goal of this thesis is to determine how a long-term exposure to virtual reality affects experiencing neuropathic pain in the case of patients with incomplete spinal cord lesions. Methods: The study included 8 probands (3 females and 5 males) aged from 30 to 64 years (average age 49.5 ± 12.0 years) from among the clients of a charitable trust "Centrum Paraple". At the entrance examination, the participants received a pair of VR BOX VR-X2 virtual reality headsets enabling viewing of two-dimensional (2D) videos in the three-dimensional (3D) format. Thereafter they were watching, in their home environment, varied therapeutic videos depicting "virtual walking" - human walking viewed from a first person perspective. After 3 months of therapeutic intervention, a follow-up examination was carried out to determine the effect of the therapy. The Neuropathy Pain Scale and the International Spinal Cord Injury Pain Basic Data Set were used to assess changes in the perception of neuropathic pain. The results were statistically processed by means of a paired t-test in the R program. To monitor objective changes in the somatosensory and motor nervous systems, the evoked...
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Neural corelates of arithmetic functions
PLASSOVÁ, Michala
This present thesis is focused on the description of relation between brain activity while solving approximate arithmetic tasks and results in Stanford Binet's intelligence test in preschool children. The influence of N1, N2 and P2p components and late posterior components on non-symbolic numerical processing has been validated. Furthermore, it is the influence of maturation with each measured component and also the difference in their amplitude and their commencement after the stimulus presentation that must be pointed out. Our research data show that it is the very amplitude and its commencement that can be used as a potential intelligence indicator in preschool children. Both these components are related to cognitive processing time which has repeatedly proved to correlate with G intelligence factor. It is especially N2 component, which is connected with inhibitiory control of executive functions, that seems to have the potential for this diagnosis. Generally, it is P2p component that is given major attention. Nevertheless, in our research, this component has shown inconsistent results with respect to the amplitude which can be attributed to a low variance of our children's intelligence.
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EEG ERP inhibitory response of selective attention in bilingual subjects
JANOUŠKOVÁ, Nikola
This bachelor thesis continues in research of bilingual subjects and investigates differences in cognitive functions (especially selective attention). It compares speed and accuracy of bilingual and monolingual responses on verbal stimuli (font detection) during which are observed subjects affected by tone with acoustic pressure of 76 dB. In theoretical part of the thesis I elaborated information about language and speech in general, language development, bilingualism, electroencephalography and of course about speech in neuropsychology. In empirical part there is described research methodology, elaboration and analysis of data, which was gained during the experiment. It?s assumed that bilingual subjects should have different values of event-related potentials, especially in linguistic part of the brain and according to behavioral data should show their cognitive advantage in less error rate. Two types of data were obtained from the experiment ? behavioral and EEG records. Behavioral data were processed in Excel and EEG records in the MATLAB programming environment. The results confirmed intergroup differences in ERP components, but these results were inconsistent within behavioral data, which can be attributed primarily to sample size.
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Vietnamese-Czech bilingual adolescents on EEG - bilingual effect on cognitive advantage
ŠIMKOVÁ, Kateřina Marie
A recently progressive topic of psychology are aspects of humans psyché. It is raised in the most complicated matter human could ever explore. In the brain. This bachelor thesis briefly concludes cerebral mechanisms of neuroplasticity and its influence on humans life. Concretely the theoretical part is specialized on a cognitive advantage of bilingualism. The mentioned advantage was studied in empirical part by electroencephalographic measurement in Vietnamese-Czech bilinguals during letter detection task. We expected bilinguals to outperform control group of monolinguals in behavioral part. Due to a different neural organization within linguistic plasticity, we also expected different amplitudes in event-related potentials in the bilingual group in linguistic areas of the brain. Results confirm mentioned neural differences, although behavioral advantage hypothesis is falsified.
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