As alteracoes na percepcao da passagem do tempo dos seres humanos tem sido investigadas em relacao as caracteristicas de diversos estimulos, condicoes corporais ou determinados tipos de tarefa. Porem, pouco se sabe sobre essas alteracoes como funcao das contingencias reforcadoras ou punitivas que controlam o comportamento. Este estudo visou investigar essa questao experimentalmente atraves do uso de um jogo virtual em computador simulando percursos de um avatar em um labirinto com 36 situacoes de escolha entre esquerda e direita. Pontos poderiam ser ganhos ou perdidos, sendo a pontuacao final convertida em titulos de nobreza hipoteticos dentro de um ranking previamente estabelecido. Tres contingencias foram manipuladas: sob Punicao (P) escolhas erradas entre direita e esquerda produziam perda de pontos; sob Reforcamento (R) escolhas certas produziam ganho de pontos; na condicao Controle (C) nao havia alteracao nos pontos. No Experimento 1 (n=60), tres grupos foram manipulados, cada um exposto a uma dessas contingencias; no Experimento 1A (n=40) novos participantes passaram pelas condicoes P e R, porem com uma alteracao na instrucao explicitando o nao perigo de morte do avatar; no Experimento 2 (n=6), cada participante foi exposto as tres condicoes experimentais, sendo manipulada a ordem de exposicao: C-P-R e C-R-P. Cada participante foi solicitado a estimar o tempo que permaneceu jogando: nos dois primeiros estudos essa solicitacao foi feita apenas apos o termino do jogo (estimativa retrospectiva); no ultimo os participantes foram informados ao inicio da primeira sessao experimental que essa solicitacao lhes seria feita ao final de cada sessao (estimativa prospectiva). Da mesma forma, ao final da sessao no Experimentos 1 e 1A, e ao final de cada sessao no Experimento 2, foi solicitada aos participantes uma avaliacao do jogo, com pontuacoes crescentes proporcionais ao grau de diversao em joga-lo. Os resultados mostraram que no Experimento 1 a condicao P produziu tempo de sessao maior que na condicao C e a condicao R produziu tempo de sessao menor do que na condicao C, sendo que no Experimento 1A as diferencas se reduziram; no Experimento 2 esse tempo foi sendo reduzido na sucessao das contingencias, independente da ordem utilizada. Nos experimentos 1 e 1A os participantes superestimaram a duracao da sessao de jogo na condicao R, e as condicoes C e P produziram estimativas proximas a duracao real. No Experimento 2 a condicao R tambem esteve associada a superestimativas na maioria dos participantes, porem sua relacao com os resultados obtidos em C e P varia entre os participantes. A magnitude da consequencia se mostrou uma variavel relevante no efeito da punicao, que foi menos acentuado no Experimento 1A. A apreciacao do jogo pelos sujeitos foi, no geral, mais positiva para a condicao P. Esses resultados apontam a interacao das contingencias operantes na percepcao temporal, sendo discutida tambem a aparente independencia entre o efeito operante da punicao e o relato verbal sobre a diversao inerente a atividade consequenciada / Alterations in the perception of the passage of time in humans have been investigated in relation to the characteristics of several stimuli, bodily conditions and certain types of task. However, little is known about these alterations as a function of reinforcing or punishing contingencies that control behavior. This study aimed to investigate this question experimentally by using a virtual computer game simulating a maze in which an avatar was faced with 36 choice situations between left and right. Points could be won or lost, the final score being converted into hypothetical titles of nobility within a predetermined ranking. Three contingencies were manipulated: under Punishment (P) \"wrong \" choices between right and left produced loss of points; under Reinforcement (R) \"right\" choices produced gain points; under control condition (C) there was no change in points at all. In Experiment 1 (n=60), three groups were manipulated, each exposed to one of these contingencies, in Experiment 1A (n=40) new participants were exposed to the conditions P and R, but with a statement explaining that there was no chance of avatar\'s death during the game, in Experiment 2 (n=6), each participant was exposed to three experimental conditions, having the sequence of exposure being manipulated: C-P-R for half the participants and C-R-P for the other half. Each participant was asked to estimate the duration spent playing: in the first two studies this request was made just after the end of the game (retrospective estimation), at the last study participants were informed at the beginning of the first experimental session that this request would be made to them end of each session (prospective estimate). Similarly, at the end of the session in Experiments 1 and 1A, and at the end of each session in Experiment 2, participants were requested a review of the game, with scores increasing with the degree of fun playing it. The results showed that in Experiment 1 the condition P produced greater session length than the condition C, and condition R produced lesser session length than condition C, whereas in Experiment 1A differences are reduced; in Experiment 2 session length was being reduced along the succession of contingencies, regardless of the sequence used. In Experiments 1 and 1A participants overestimated the duration of the game session under the condition R, and C and P conditions produced close to the actual duration estimates. In Experiment 2 the R condition was also associated with overestimation in the majority of participants, however its relationship to the results obtained in C and P varies between participants. The magnitude of the result proved to be a relevant variable in the effect of punishment, which was less pronounced in Experiment 1A. The enjoyment of the game by the subjects was generally more positive for condition P. These results indicate the interaction of operant contingencies on time perception, and also discussed the apparent independence between the operant effect of punishment and verbal report about the fun inherent in activity that was punished

Gegenstand dieser Arbeit ist die Divergenz zwischen subjektiver und objektiver Zeitwahrnehmung. In drei empirischen Studien wird untersucht, wie Zeitwahrnehmung vom Inhalt eines Zeitintervalls beeinflusst wird. Dabei werden Paradigmen aus der Forschung zur visuellen Wahrnehmung mit Messungen der Zeitwahrnehmung kombiniert und durch Ableitungen neuronaler Aktivität (Elektroenzephalographie) ergänzt. Sensorische Modelle der Zeitwahrnehmung basieren auf der Annahme, dass die subjektive Dauer eines sensorischen Reizes in den selben neuronalen Netzwerken entsteht, die den Reiz selbst verarbeiten. Unter dieser Annahme müsste jede Veränderung des Reizes, welche neuronale Verarbeitung hervorruft, auch einen Effekt auf die wahrgenommene Dauer des Reizes haben, auch wenn diese Eigenschaft nicht bewusst wahrgenommen wird. Die Ergebnisse zeigen jedoch das nur Veränderungen die auch bewusst wahrgenommen werden einen Einflusss auf subjektive Dauer haben. Darüberhinaus zeigte sich, dass die subjektiv wahrgenommene Stärke der Veränderung die subjektive Dauer bestimmt. Die Befunde sprechen eher für das Modell einer zentrale inneren Uhr, das jedoch auch erklären muss, mittels welcher Mechanismen der Inhalt eines Zeitintervalls dessen subjektive Dauer beeinflusst. Anhand elektrophysiologischer Korrelate der Zeitwahrnehmung wird untersucht, ob die Dynamik visueller Reize die Zeitwahrnehmung schon während des Enkodierens der Zeit beeinflusst, oder erst später wenn eine Entscheidung über die Dauer des Zeitintervalls getroffen wird. Die Ergebnisse zeigen, dass die neuronalen Korrelate der Zeitwahrnehmung nicht die zeitliche Verzerrung widerspiegeln, die durch dynamische Reize hervorgerufen wird. Dies spricht dafür, dass diese Verzerrung auf einer späteren Prozessstufe eintritt. Insgesamt zeigen die Befunde der drei Studien, das Zeitwahrnehmung zwar stark vom sensorischen Inhalt beeinflusst wird, sich aber nicht direkt von der sensorischen Reizverarbeitung ableiten lässt. / Often, perceived time differs from objective time. This work addresses how perceived time is influenced by the content of a time interval. Three empirical studies were conducted to assess how visual stimulus dynamics affect perceived duration. We combined paradigms from vision research with timing tasks and measures of neural processing using electroencephalogram (EEG). Sensory models of interval timing claim that duration of a time interval is encoded in the same neural networks that process its sensory content. Thus, even stimulus dynamics that are processed only on the sensory level but are not consciously perceived should affect perceived duration. In contrary, we showed that only consciously perceived stimulus dynamics affect perceived duration, with more perceived dynamics leading to longer perceived duration. Changes that were not perceived but evoked a neural response (measured in the EEG) did not affect perceived duration. These findings argue against the assumption of sensory timing models, but are consistent with models that assume a central internal clock. However, internal clock models do not sufficiently explain why stimulus dynamics affect perceived duration. We tested whether stimulus dynamics affect the stage of temporal encoding as postulated by internal clock models, by measuring neural correlates of temporal encoding in the EEG. We found that the neural correlates of temporal encoding reflected internal variations in perceived duration, but not the dilation induced by stimulus dynamics. We argue that visual stimulus dynamics affect perceived duration after temporal encoding. In sum, the findings show that duration perception is not grounded in early sensory processing, but is probably achieved by a specialized timing system that can be biased by the perception of dynamic stimuli. The discussion addresses theoretical implication of these findings for theories of time perception, and their implications for further research in the field.

As alteracoes na percepcao da passagem do tempo dos seres humanos tem sido investigadas em relacao as caracteristicas de diversos estimulos, condicoes corporais ou determinados tipos de tarefa. Porem, pouco se sabe sobre essas alteracoes como funcao das contingencias reforcadoras ou punitivas que controlam o comportamento. Este estudo visou investigar essa questao experimentalmente atraves do uso de um jogo virtual em computador simulando percursos de um avatar em um labirinto com 36 situacoes de escolha entre esquerda e direita. Pontos poderiam ser ganhos ou perdidos, sendo a pontuacao final convertida em titulos de nobreza hipoteticos dentro de um ranking previamente estabelecido. Tres contingencias foram manipuladas: sob Punicao (P) escolhas erradas entre direita e esquerda produziam perda de pontos; sob Reforcamento (R) escolhas certas produziam ganho de pontos; na condicao Controle (C) nao havia alteracao nos pontos. No Experimento 1 (n=60), tres grupos foram manipulados, cada um exposto a uma dessas contingencias; no Experimento 1A (n=40) novos participantes passaram pelas condicoes P e R, porem com uma alteracao na instrucao explicitando o nao perigo de morte do avatar; no Experimento 2 (n=6), cada participante foi exposto as tres condicoes experimentais, sendo manipulada a ordem de exposicao: C-P-R e C-R-P. Cada participante foi solicitado a estimar o tempo que permaneceu jogando: nos dois primeiros estudos essa solicitacao foi feita apenas apos o termino do jogo (estimativa retrospectiva); no ultimo os participantes foram informados ao inicio da primeira sessao experimental que essa solicitacao lhes seria feita ao final de cada sessao (estimativa prospectiva). Da mesma forma, ao final da sessao no Experimentos 1 e 1A, e ao final de cada sessao no Experimento 2, foi solicitada aos participantes uma avaliacao do jogo, com pontuacoes crescentes proporcionais ao grau de diversao em joga-lo. Os resultados mostraram que no Experimento 1 a condicao P produziu tempo de sessao maior que na condicao C e a condicao R produziu tempo de sessao menor do que na condicao C, sendo que no Experimento 1A as diferencas se reduziram; no Experimento 2 esse tempo foi sendo reduzido na sucessao das contingencias, independente da ordem utilizada. Nos experimentos 1 e 1A os participantes superestimaram a duracao da sessao de jogo na condicao R, e as condicoes C e P produziram estimativas proximas a duracao real. No Experimento 2 a condicao R tambem esteve associada a superestimativas na maioria dos participantes, porem sua relacao com os resultados obtidos em C e P varia entre os participantes. A magnitude da consequencia se mostrou uma variavel relevante no efeito da punicao, que foi menos acentuado no Experimento 1A. A apreciacao do jogo pelos sujeitos foi, no geral, mais positiva para a condicao P. Esses resultados apontam a interacao das contingencias operantes na percepcao temporal, sendo discutida tambem a aparente independencia entre o efeito operante da punicao e o relato verbal sobre a diversao inerente a atividade consequenciada / Alterations in the perception of the passage of time in humans have been investigated in relation to the characteristics of several stimuli, bodily conditions and certain types of task. However, little is known about these alterations as a function of reinforcing or punishing contingencies that control behavior. This study aimed to investigate this question experimentally by using a virtual computer game simulating a maze in which an avatar was faced with 36 choice situations between left and right. Points could be won or lost, the final score being converted into hypothetical titles of nobility within a predetermined ranking. Three contingencies were manipulated: under Punishment (P) \"wrong \" choices between right and left produced loss of points; under Reinforcement (R) \"right\" choices produced gain points; under control condition (C) there was no change in points at all. In Experiment 1 (n=60), three groups were manipulated, each exposed to one of these contingencies, in Experiment 1A (n=40) new participants were exposed to the conditions P and R, but with a statement explaining that there was no chance of avatar\'s death during the game, in Experiment 2 (n=6), each participant was exposed to three experimental conditions, having the sequence of exposure being manipulated: C-P-R for half the participants and C-R-P for the other half. Each participant was asked to estimate the duration spent playing: in the first two studies this request was made just after the end of the game (retrospective estimation), at the last study participants were informed at the beginning of the first experimental session that this request would be made to them end of each session (prospective estimate). Similarly, at the end of the session in Experiments 1 and 1A, and at the end of each session in Experiment 2, participants were requested a review of the game, with scores increasing with the degree of fun playing it. The results showed that in Experiment 1 the condition P produced greater session length than the condition C, and condition R produced lesser session length than condition C, whereas in Experiment 1A differences are reduced; in Experiment 2 session length was being reduced along the succession of contingencies, regardless of the sequence used. In Experiments 1 and 1A participants overestimated the duration of the game session under the condition R, and C and P conditions produced close to the actual duration estimates. In Experiment 2 the R condition was also associated with overestimation in the majority of participants, however its relationship to the results obtained in C and P varies between participants. The magnitude of the result proved to be a relevant variable in the effect of punishment, which was less pronounced in Experiment 1A. The enjoyment of the game by the subjects was generally more positive for condition P. These results indicate the interaction of operant contingencies on time perception, and also discussed the apparent independence between the operant effect of punishment and verbal report about the fun inherent in activity that was punished

Organismos são capazes de diferenciar estímulos sensoriais gerados independentemente pelo ambiente dos estímulos causados por sua própria ação no mundo. Esse processo depende de mecanismos neurais e cognitivos que unam suas ações às percepções por elas geradas. Objetivo desse trabalho foi investigar a interação da ação com a percepção visual no domínio temporal. Em cinco experimentos psicofísicos, foi estudado o efeito modulatório da ação no efeito flash-lag e em tarefas envolvendo estimativas de intervalos temporais. Nossos resultados mostraram que o planejamento e/ou execução de atos motores voluntários são capazes de reduzir em algumas dezenas de milissegundos as latências com que estímulos visuais são percebidos e também de reduzir as estimativas de intervalos temporais. A redução dessas latências é maior quando a conseqüência sensorial da ação é apresentada na fóvea, assim como quando existe um atraso entre a ação e o estímulo por ela causado. / Organisms are able to distinguish between sensory stimuli from the environment and sensory stimuli they cause. This process depends on neural and cognitive mechanisms that link actions to perceptions generated by these actions. This work aimed to investigate the interaction of action and perception in the temporal domain. In five psychophysical experiments, we have assessed the modulation of action in the flash-lag effect and in tasks involving temporal interval estimations. Our results showed that the planning and execution of a voluntary motor action are capable of reducing both visual perceptual latencies and temporal interval estimations. This reduction increases when the sensory consequences of motor actions are presented on the fovea and when a delay is injected between the action and the stimuli caused by it.

Enligt tidigare forskning upplever människor att tiden går fortare i lugna trygga miljöer och går långsamt i påfrestande situationer. Något som skapar lugna trygga känslor hos människor är färgen blå medans färgen gul som har ett ständigt tröttande ljus upplevs som påfrestande. Vilket i teorin ska innebära att människor som tittar på något blått upplever att tiden går snabbare än de som betraktar något gult. I föreliggande studie har detta undersökts med två experiment, i första experimentet fick deltagarna slå multiplikationstal på kalkylatorn på en dator medan det var en blå eller gul bakgrund. I det andra experimentet fick deltagarna se en snurra på en gul eller blå bakgrund. I inget av experimenten upptäcktes någon signifikant skillnad. I experimentet var det dessutom fler som svarade att de ville använda den blåa bakgrunden om den fick tiden att upplevas gå fortare än den gula.

Avhandlingen handlar om prospektivt minne (PM) hos personer med utvecklingsstörning. PM syftar på att formulera intentioner och genomföra dessa någon gång i framtiden, antingen inom en definierad tidsram eller i samband med en specifik händelse. Frågeställningar: 1. Finns det en kvalitativ och kvantitativ skillnad mellan prospektivt minne hos personer med utvecklingsstörning och en kontrollgrupp? (Artikel I – II) 2. Hur ser sambandet mellan prospektivt minne, arbetsminne och episodiskt minne ut hos personer med utvecklingsstörning och, skiljer sig detta åt jämfört med kontrollgruppen? (Artikel II) 3. Vilka förutsättningar vid inkodning och hågkomst är kompatibla? (Artikel III) 4. På vilket sätt kan svag association mellan olika delar av information bidra till prospektiva minnesfel? (Artikel IV) 5. Går det att särskilja en hög- respektive lågpresterande grupp personer med utvecklingsstörning med avseende på prospektiv minnesprestation? (Artikel II) Personer med utvecklingsstörning begår fler prospektiva minnesfel än personer i kontrollgruppen. Motsvarande gruppskillnad finns inte för självskattat minne. Prospektiv minnesprestation är bättre med bilder jämfört med ord som prospektiva ledtrådar, mest tydligt för personer med utvecklingsstörning. Arbetsminneskapacitet visade ett samband med både prospektivt minne och antalet falska minnen i kognitivt krävande situationer, till exempel, situationer med flera parallella prospektiva minnesuppgifter. Falska minnen och prospektivt minne hade ett samband hos personer med utvecklingsstörning. Att felaktigt känna igen bilder med bara delvis bekanta delar och att känna igen prospektiva ledtrådar utan att komma ihåg själva intentionen hade ett samband hos personer med utvecklingsstörning. Personer med utvecklingsstörning var också sämre än kontrollgruppen på att upprepa tidsintervall. Detta kan till exempel bero på bristande episodiskt minne och begränsade strategier för att lösa den här typen av uppgifter. Resultaten diskuteras i relation till träning av prospektivt minne och val av hjälpmedel. / This thesis deals with prospective memory (PM) in individuals with intellectual disability. The term refers to planning and executing actions that cannot be performed immediately and have to be stored in memory and retrieved either within a specified timeframe or to be associated with a specific event. Following research questions were explored: 1. Does prospective memory performance in the intellectual disability group differ quantitatively and qualitatively compared to a control group of individuals without intellectual disability? (Paper I – II) 2. What are the relations between prospective memory, working memory and episodic memory in individuals with intellectual disability, and how are these relations different from the relations found in individuals without intellectual disability? (Paper II) 3. What conditions constitute compatibility between encoding and retrieval of prospective memory tasks? (Paper III) 4. In what way might weak binding contribute to PM failure? (Paper IV) 5. Is it possible to identify high and low PM-performing groups of individuals with intellectual disability? (Paper II) The results of the studies demonstrated that individuals with intellectual disability commit more PM errors than individuals in the control group, despite similarities in self-rated memory. Pictures as PM cues improved PM performance in comparison to words in both groups. This may be important primarily for recognition of the PM cue, particularly in the intellectual disability group. As to working memory capacity, it also shows a relation to both PM performance and binding performance in cognitively demanding situations (e.g., tasks with multiple parallel PM tasks). Furthermore, it was found that binding is related to PM performance in the intellectual disability group as there is a relationship between feature errors and recognition of cues, though not retrieving the correct intention. Finally, time reproduction was found to be weak in the intellectual disability group compared to the control group. This may be due to, for example, weak episodic memory and limited strategies for solving this type of task. These findings are discussed in relation to PM training and PM aids.

No description available.

Το ηλεκτροεγκεφαλογράφημα αποτελεί μία μέθοδο καταγραφής των ηλεκτρικών σημάτων που παράγονται στο εσωτερικό του εγκεφάλου. Τα ηλεκτρικά αυτά σήματα διαχέονται από το σημείο που παράγονται προς την εξωτερική δερματική επιφάνεια του κρανίου όπου μετρώνται ως διαφορές δυναμικού. Αντικείμενο της διπλωματικής εργασίας είναι η σχεδίαση και η υλοποίηση μίας πειραματικής συνθήκης και της αντίστοιχης πειραματικής διάταξης, η οποία θα επιτρέπει την καταγραφή των Προκλητών δυναμικών του ατόμου που θα εκτελεί το πείραμα. Το κλινικό πρωτόκολλο που χρησιμοποιήθηκε εξετάζει δύο βασικά θέματα. Το πρώτο αφορά την αντίληψη του ανθρώπου για το χρόνο και το δεύτερο το πώς επηρεάζουν τα υποσυνείδητα μηνύματα τη λήψη αποφάσεων και την εγκεφαλική λειτουργία. Αρχικά, στο πρώτο κεφάλαιο της παρούσας διπλωματικής εργασίας, αναφέρονται οι βασικές αρχές του ηλεκτροεγκεφαλογραφήματος και το σύστημα διάδοσης της πληροφορίας στον ανθρώπινο εγκέφαλο. Επιπλέον περιγράφεται ο τρόπος με τον οποίο γίνεται η καταγραφή του σήματος του εγκεφαλογραφήματος και των Προκλητών Δυναμικών. Στη συνέχεια, στο δεύτερο κεφάλαιο παρουσιάζεται η θεωρία στην οποία βασίστηκε ο σχεδιασμός του κλινικού πρωτοκόλλου και η οποία αφορά δύο θέματα, την αντίληψη του ανθρώπου για το χρόνο και την επιρροή των υποσυνείδητων μηνυμάτων στη λήψη αποφάσεων. Στα επόμενα κεφάλαια περιγράφεται το κλινικό πρωτόκολλο που χρησιμοποιήθηκε και οι πειραματικές συνθήκες που εξετάστηκαν κατά τη διεξαγωγή των πειραμάτων. Ακόμα, γίνεται περιγραφή τόσο του υλικού όσο και του λογισμικού μέρους της πειραματικής διάταξης που αναπτύχθηκε για την υλοποίηση του κλινικού πρωτοκόλλου. Η πειραματική διάταξη που αναπτύχθηκε στα πλαίσια της διπλωματικής επιτρέπει τη σύνδεση με Ηλεκτροεγκεφαλογράφο με αποτέλεσμα τον συγχρονισμό της πειραματικής ακολουθίας και της καταγραφής του ηλεκτροεγκεφαλογραφήματος και των Προκλητών Δυναμικών. Με την πειραματική διάταξη που αναπτύχθηκε έγιναν δύο πειράματα. Η καταγραφή της εγκεφαλικής δραστηριότητας του κάθε εξεταζόμενου (ΗΕΓ) ήταν συνεχής για όλη τη διάρκεια της δοκιμασίας. Η εξαγωγή των Προκλητών Δυναμικών έγινε μετά το τέλος της καταγραφής με το πρόγραμμα EEGLAB, με το οποίο έγινε και η επεξεργασία τους. Τα Προκλητά Δυναμικά απεικονίστηκαν τόσο σε δισδιάστατα όσο και σε τρισδιάστατα μοντέλα κεφαλιών ενώ εξετάστηκε και το φασματικό περιεχόμενο του σήματος του ηλετροεγκεφαλογραφήματος για τις διάφορες πειραματικές συνθήκες. Από την ανάλυση των καταγραφών παρατηρήθηκαν κάποιες διαφορές μεταξύ των συνθηκών του πειράματος οι οποίες περιείχαν υποσυνείδητα μηνύματα και αυτών που δεν περιείχαν. Οι κορυφώσεις του δυναμικού εντοπίστηκαν τις ίδιες χρονικές στιγμές για όλες τις συνθήκες ενώ το πλάτος τους ήταν διαφορετικό μεταξύ των συνθηκών στις οποίες δινόταν στους εξεταζόμενους η σωστή απάντηση με υποσυνείδητο μήνυμα και σε αυτές που δεν δινόταν. / The electroencephalogram constitutes a method for recording electrical signals produced in the interior of the brain. These electric signals are diffused from the point of the brain where they are produced to the exterior dermal surface of the skull where they are measured as potential differences. The object of this diploma thesis is the design and the development of an experiment and the corresponding experimental setup, which allows the recording of the Event Related Potentials of the person who executes the experiment. The clinical protocol that is used examines two fundamental issues. The first is related to time perception while the second one examines if and how subliminal messages influence the decision making and the cerebral operation. Initially, in the first chapter of the present diploma thesis, the fundamentals of the Electroencephalogram and the system that is responsible for the distribution of the information inside the human brain is described. Following, Electroencephalogram and Event Related Potentials (ERPs) recordings are described. In the second chapter the theory on which the planning of the clinical protocol was based is presented. It concerns two research fields of psychophysiology; time perception and the influence of subliminal messages in decision-making. In the next chapters the clinical protocol and the experimental conditions that were examined during the experiments are described. Furthermore, there is a description of both the software and the hardware modules of the developed system. The experimental setup that was developed in the framework of the diploma thesis allows the connection to an Electroencephalograph and appropriate trigger signals are used in order to synchronize stimuli and recordings of EEG and ERPs. Two experiments were conducted. The recording of the brain activity was continuous for the whole duration of the experimental procedure. The Event Related Potentials were extracted post-hoc, after the end of the recording, using the EEGLAB software. The Event Relates Potentials were mapped both on two-dimensional and on three-dimensional head models. The spectrum of the electroencephalogram was also examined for the various experimental conditions. Analysis of the recordings revealed differences between the experimental conditions that contained subliminal messages in the EEG and ERPs. The ERPs’ peaks were detected at the same time delays for all the conditions. However, the amplitude of the peaks differed between the conditions where the right answers were given with subliminal messages and those that did not contain any subliminal messages.

Tyrimo tikslas: išsiaiškinti, kaip skiriasi įvairių kursų medicinos studentų mirties baimė, laiko suvokimas ir streso įveikos būdai. Tyrime dalyvavo 227 respondentai: 70 ne medikų, 61 - I kurso, 33 - II kurso, 22 - V kurso, 41 - VI kurso LSMU medicinos fakulteto studentai. Tiriamieji pasirinkti atsitiktinės atrankos būdu. Siekiant išsiaiškinti, kaip skiriasi įvairių kursų medicinos studentų mirties baimė, laiko suvokimas ir streso įveikos būdai, pagrindiniu tyrimo metodu pasirinkta anketinė apklausa. Apklausos dalyviams buvo pateikti trys klausimynai: Colett-Lester mirties bei mirimo baimės skalė (angl. The Revised Collet-Lester Fear of Death And Dying Scale – Lester, 1990), skirta išsiaiškinti savo paties ir kitų mirties baimę bei mirties proceso baimę; Šešių faktorių modelis - ZTPI laiko suvokimo skalė (angl. Zimbardo Time Perspective Inventory, 1990) bei profesoriaus G.Valicko ir doktoranto Ž. Grakausko (2006) sudarytas streso įveikos klausimynas: keturių faktorių modelis, skirtas streso įveikos vertinimui atlikti. Klausimynų pildymo laikas vidutiniškai 15 minučių. Darbo uždaviniai: išanalizuoti ir palyginti I -II ir V-VI kursų medicinos studentų mirties baimę, laiko suvokimą bei streso įveikos būdus atskirose merginų ir vaikinų grupėse; bei išanalizuoti ir palyginti medicinos studentų bei apklausoje dalyvavusių atsitiktinės atrankos respondentų (ne medikų) mirties baimę, laiko suvokimą ir streso įveikos būdus. Tyrimo rezultatai parodė, kad I-II kursų medicinos... [toliau žr. visą tekstą] / The aim of the research was to assess the differences in fear of death, time perception and stress coping techniques of the various courses medical students. Analyze needs for medical students to successful learning outcomes. There were questioned 227 people, from whom 70 aren’t medical students, 61 - I course, 33 - II course, 22 - V course and 41 - VI course medical students from faculty of medicine in Lithuanian University of Health Sciences. In case that we want to know how various students can overcome fear of death, time perception and stress coping means, we choose questionnaires form. The subjects were invited to complete questionnaires in 15 minutes. All medical students in the survey took place before and after the lab. All medical students in the survey took place before and after the lab. There was introduce free questionnaires: The Revised Collet-Lester Fear of Death And Dying Scale – (Lester, 1990) which is dedicate to know yourself and other peoples fear of death and dying scale, Zimbardo Time Perspective Inventory (1990) and the stress overcome questionnaire about four factors models which are dedicate to appreciate the fear of death which was done professor’s G. Valickas and the doctors Ž. Grakauskas (2006). The aim of study shows that I-II course students fear of death is not very expressible, they don‘t have any problems with time perception and there is no more effective ways to avoid stress when fourth course students are using. There was doing test how... [to full text]

Orientador: Prof. Dr. Yossi Zana / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Neurociência e Cognição, 2017.