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Il apparaît, suite aux résultats de plusieurs études comportementales et d’imagerie cérébrale, que les hormones gonadiques peuvent moduler le fonctionnement cérébral chez la femme. Les asymétries cérébrales fonctionnelles (ACFs), en particulier, changeraient en fonction du niveau de progestérone et d’œstrogène. On a également observé que lorsque le taux d’œstrogène est bas, les performances aux tâches impliquant l’hémisphère droit sont améliorées. Par contre, les preuves de l’action physiologique de ces deux hormones sur le cerveau ne sont pas très nombreuses. Le peu d’études d’électrophysiologie cognitive qui ont porté sur les effets du cycle menstruel ont rapporté que la composante P300 y serait sensible. Aucune n’a cependant utilisé une tâche d’habileté spatiale ou de rotation mentale qui sont connues pour impliquer davantage l’hémisphère droit. Le but de la présente étude est de documenter les changements électrocorticaux reliés aux variations hormonales lors d’une tâche de rotation mentale. Notre hypothèse de départ est que le taux d’œstrogène influencera l’activité électrocorticale et la latéralisation. Les potentiels évoqués cognitifs ont été comparés chez les mêmes femmes (n=12) lors d’une tâche de rotation mentale, répétée à deux périodes du cycle menstruel. Nos résultats démontrent que la condition de rotation induit une latéralisation de l’activité pariétale, vers l’hémisphère gauche, quand le niveau d’œstrogène est bas. Par contre, lorsque le niveau d’œstrogène est élevé, il n’y a aucune latéralisation. Par ailleurs, nous avons observé une augmentation de l’amplitude de la P300 lors du niveau oestrogénique élevé. En conclusion, les fluctuations oestrogéniques du cycle menstruel ont un impact sur la latéralisation de l’activité électrocorticale, lors d’un effort de rotation mentale. / After many behavioral and some neuroimaging studies, it appears that the gonadic hormones can modulate the neuronal function of women's brain. In particular, the functional cerebral asymmetries can be affected by the level of progesterone and estrogens. It has been observed that when the level of estrogen is low, the performance at task that engages more the right hemisphere is enhanced. However, there is a lack of evidence for the physiological actions of these two hormones on the brain. The few event-related potential studies taking into account the menstrual cycle effects, had noticed that the component P300 can be affected. No electrophysiological study has used a mental rotation task or spatial ability tests which are known for their right hemisphere dominance. The aim of the present research is to document the effect of hormonal variations on the electrocortical activity, using a mental rotation task. Our hypothesis is that estrogen levels affect electrocortical activity and lateralization. The ERPs were compared in the same women (n = 12) during a mental rotation task, repeated over two periods of the menstrual cycle. Our results show a lateralization of the left parietal activity when estrogen levels are low and during the rotation. Whereas when the estrogen level is high, there is no lateralization. In addition, we observed an increase in the amplitude of P300 for this same high level. In conclusion, estrogens fluctuations associated with the menstrual cycle have an impact on the lateralization of electrocortical activity, when a mental rotation is needed.

Une interface cerveau-ordinateur permet d'interagir avec un système, comme un système d'écriture, uniquement par l'activité cérébrale. Un des phénomènes neurophysiologiques permettant cette interaction est le potentiel évoqué cognitif P300, lequel correspond à une modification du signal 300 ms après la présentation d'une information attendue. Cette petite réaction cérébrale est difficile à observer par électroencéphalographie car le signal est bruité. Dans cette thèse, de nouvelles techniques basées sur la théorie des ondelettes sont développées pour améliorer la détection des P300 en utilisant des mesures de similarité entre les canaux électroencéphalographiques. Une technique présentée dans cette thèse débruite les signaux en considérant simultanément la phase des signaux. Nous avons également étendu cette approche pour étudier la localisation du P300 dans le but de sélectionner automatiquement la fenêtre temporelle à étudier et faciliter la détection / Brain-Computer Interfaces (BCI) are control and communication systems which were initially developed for people with disabilities. The idea behind BCI is to translate the brain activity into commands for a computer application or other devices, such as a spelling system. The most popular technique to record brain signals is the electroencephalography (EEG), from which Event-Related Potentials (ERPs) can be detected and used in BCI systems. Despite the BCI popularity, it is generally difficult to work with brain signals, because the recordings contains also noise and artifacts, and because the brain components amplitudes are very small compared to the whole ongoing EEG activity. This thesis presents new techniques based on wavelet theory to improve BCI systems using signals' similarity. The first one denoises the signals in the wavelet domain simultaneously. The second one combines the information provided by the signals to localize the ERP in time by removing useless information

Introdução: O P300 é um potencial evocado auditivo que ocorre aproximadamente 300 milissegundos (ms) após a apresentação do estímulo. Geralmente, é evocado ao se utilizar o paradigma tradicional, no qual são apresentados dois estímulos perceptivelmente diferentes: um estímulo frequente (85%) e um estímulo raro (15%). Os indivíduos são orientados a indicar, de alguma maneira, a quantidade de estímulos raros que perceberam durante a realização do exame. O P300 é considerado um potencial endógeno, pois ocorre devido a um evento cognitivo (decisão da ocorrência do estímulo raro). Contudo, alguns estudos mostraram que as características acústicas do estímulo podem interferir no potencial, evidenciando uma contribuição exógena ou sensorial para evocar a resposta. Essas implicações endógenas e exógenas para evocar o P300 ainda não foram totalmente definidas. A avaliação desses aspectos específicos pode ajudar a identificar os geradores desse potencial. Objetivo: verificar o efeito da contribuição endógena e exógena para obtenção do P300, utilizando paradigma tradicional e o paradigma de omissão. Métodos: participaram desse estudo 30 indivíduos jovens adultos, normo-ouvintes sem alteração neurológica ou psiquiátrica aparente. Os indivíduos foram avaliados com o paradigma tradicional (estímulo frequente: 800 Hz; estímulo raro 1200 Hz) e com o paradigma de omissão (estímulo frequente: 800 Hz; estímulo raro: ausência de som). Cada orelha foi avaliada separadamente por ambos os paradigmas na intensidade de 80 dBNPS. Foram apresentados 300 estímulos (45 raros) em cada estimulação. Para a obtenção do P300, foi utilizado o equipamento \"Neuroscan Stim2\" com 12 eletrodos ativos no escalpo, colocados nas seguintes posições: FPz, F4, Fz, F3, C4, Cz, C3, CP6, CP5, P4, Pz e P3. O maior pico após o complexo N1-P2-N2 foi considerado como P300. A amplitude foi medida considerando a linha de base do intervalo pré-estímulo, enquanto a latência foi medida no maior pico positivo. Nesse estudo, foi utilizada a Análise de Variância (ANOVA) com medidas repetidas. Foram realizados mapas topográficos do escalpo para ambas as estimulações. Resultados: para todos os 12 eletrodos analisados nesse estudo, a média da latência em milissegundos foi significantemente menor, e a média da amplitude foi significantemente maior para o paradigma tradicional quando comparado ao paradigma de omissão. Além disso, a morfologia da onda foi mais bem definida para o paradigma tradicional. Os mapas topográficos para ambos os paradigmas mostraram uma ativação mais generalizada e mais positiva na região centro-parietal, indicando que as mesmas áreas foram ativadas em ambos os paradigmas. Conclusão: o presente estudo demonstrou que o estímulo acústico, ausente no paradigma de omissão, influencia a latência, amplitude e morfologia da onda, evidenciando uma contribuição exógena/sensorial para obtenção do potencial / Introduction: The P300 is an auditory evoked potential that occurs approximately 300 ms after the stimulus presentation. It is usually elicited by a traditional paradigm in which two perceptually different stimuli are randomly presented with different proportions - one is frequent (85%) and the other is rare (15%). The tested individual is instructed to somehow indicate the amount of rare stimuli heard. According to the literature, P300 is considered an endogenous potential since it occurs in response to a cognitive event (i.e. decision of the occurrence or not of the rare stimulus). However, few studies have shown that the acoustic characteristics of the stimuli might influence the potential, evidencing some exogenous or sensorial contribution to the response formation. The implications that endogenous and exogenous contributions have to eliciting the P300 are not fully understood yet. The assessment of their specific roles would help to identify the P300 generators. Objective: To verify the effects of the endogenous and exogenous contribution to obtain/elicit the P300 using both the traditional and the omission paradigms. Methods: Thirty normal hearing young adults, without known neurological or psychiatric disorders, participated in this study. The individuals were assessed using P300 elicited by the traditional paradigm (frequent stimulus: 800 Hz; rare stimulus: 1200Hz) and by the omission paradigm (frequent stimulus: 800 Hz; rare stimulus: absence of sound). Both paradigms were presented to one ear at a time, at 80dBSPL, and 300 stimuli (45 rare) were presented in each stimulation. The \"Neuroscan Stim2\" was used to obtain the P300 with 12 active electrodes fixed at the following positions: FPz, F4, Fz, F3, C4, Cz, C3, CP6, CP5, P4, Pz e P3. The largest peak after the N1-P2-N2 complex was considered the P300. Its amplitude was measured considering the pre-stimulation response baseline, while its latency was measured at the most positive peak. The Analysis of Variance (ANOVA) with repeated measures was used in this study. Topographic maps from the scalp to both paradigms were also analyzed. Results: To all 12 electrodes positions analyzed in this study, the mean latency (ms) was significantly earlier and the mean amplitude (?V) was significantly larger for the traditional paradigm compared to the omission paradigm. Also, better wave morphology was obtained for the traditional paradigm. The topographic maps to both paradigms has shown more generalized and positive activation at the centro-parietal region, indicating that the same brain areas were involved in both paradigms. Conclusion: The current study has demonstrated that the acoustic stimulus, absent on the omission paradigm, have an impact on the wave formation in respect to its latency, amplitude and morphology, evidencing the influence of sensorial information to the P300

Les difficultés de théorie de l’esprit (ToM) associées à la schizophrénie (SZ) et la schizotypie (Szt) seraient dues à un trouble élémentaire de traitement du contexte. Or, traiter le contexte engagerait deux types de processus inégalement atteints dans la SZ: les processus prédictifs (génération de prédictions) seraient préservés et les processus intégratifs (intégration a posteriori des informations nouvelles avec le contexte) seraient altérés. Ces processus sont mobilisés lors de la production d’inférences et reflétés par la modulation de la N400 ou de la P600. À l’aide de mesures comportementales et électrophysiologiques, l’objectif de ce travail était de: a) vérifier l’inégale atteinte de ces processus dans la Szt, b) évaluer si ce pattern d’inégale atteinte est observé lors d’une tâche de production d’inférences intentionnelles (PII), c) faciliter la mobilisation des processus altérés par le renforcement du contexte (sémantique, ajout d’un indice social). L’étude réalisée avec un paradigme d’amorçage sémantique en contexte mot confirme l’altération spécifique des processus intégratifs dans la Szt. La suite des études, conduite autour d’une tâche de PII reposant sur les processus prédictifs ou intégratifs dans la SZ et la Szt, montre: 1) des difficultés de PII lorsqu’elle mobilise les processus intégratifs, 2) une réduction de ces difficultés par le renforcement sémantique et 3) que l’ajout d’un indice social pourrait faciliter le traitement du contexte. Ainsi, la PII n’est pas totalement altérée dans la Szt et la SZ. Les études futures devraient considérer cette inégale atteinte des processus en ToM pour aider les patients à attribuer des intentions à autrui. / Theory of mind (ToM) impairments in schizophrenia (SZ) and in schizotypy (Szt) may stem from a context-processing deficit. However, treating the context would involve two types of processes differently affected impacted in SZ: predictive strategy (generation of expectations) would be preserved and integrative strategy (retroactive integration of new information with the context) would be altered. These processes are mobilized during inference generation tasks and reflected by modulations of the N400 and P600 components. Using behavioral and electrophysiological measures, the aim of this thesis was to: (a) confirm the unequal alteration of these processes in the Szt, (b) assess whether this pattern of unequal alteration is observed in intentional inference production tasks (IIP), and (c) facilitate the mobilization of altered processes by increasing the contextual constraints (semantic constraint, contextual reinforcement by social cue). Using a semantic priming task in word context, a first study showed that integrative processes are specifically altered in Szt. Subsequent studies were based on IIP task in which the inference production involved predictive processes or integrative processes. Results showed that: (1) difficulties were observed only when IIP involved integrative processes, (2) semantic constraints decreased these difficulties and (3) context processing may be facilitated by the addition of a social cue. Thus, IIP is not totally altered in Szt and SZ. Future studies should consider this unequal impact of ToM processes to help patients attribute intentions to others.

Objective: Attention Bias Modification Training (ABMT) for anxiety aims to train attention away from threatening stimuli and toward neutral stimuli. Although ABMT shows promising anxiety reduction effects in children and adolescents, no study has examined its influence on neural indicators of attention measured using event-related potentials (ERPs) in children or adolescents (i.e., youths). The present study examined the influence of ABMT on the P1, N170, P2 and P3 ERP components during completion of the emotional faces dot probe task in youths with anxiety disorders who failed to respond to cognitive behavioral therapy. Method: Thirty youths (M age = 11.97, SD = 2.89) with primary DSM-IV-TR anxiety disorders completed the dot probe task while undergoing electroencephalogram (EEG) to obtain ERPs before, immediately after, and eight weeks after eight sessions of either ABMT (n = 14) or a control task regimen (CT), (n = 16). Results: At post-treatment, statistically significant effects were found for P1 and P3 mean amplitudes: P1 was significantly higher during trials showing neutral-neutral (NN) face pairs in the ABMT arm than in the CT arm; P3 was significantly higher during trials showing NN face pairs than during trials showing neutral-threat (NT) face pairs in the ABMT arm, but not the CT arm. At eight-week follow-up, participants in both arms showed significantly higher (more negative) N170 responses for NN trials than for NT trials. Conclusions: Attention Bias Modification Treatment led to increases in neural processing of neutral stimuli in early and late stage attentional processing, as measured by the P1 and P3 components, respectively. These components during the dot probe task are promising neural markers of ABMT’s effects on attentional processing in youth with anxiety disorders.

L’addiction à l’alimentation (AA) est un concept ancien, mais encore sujet de controverses qui toucherait 18 à 24 % des obèses. Dans cette thèse, nous nous sommes intéressés aux intrications entre régulations du comportement alimentaire, addiction et AA, afin de mieux comprendre les mécanismes liés à la désinhibition de la prise alimentaire. Notre travail a conduit à plusieurs résultats : 1) Une revue de la littérature a permis de montrer l’existence d’interaction étroite entre les niveaux de régulation du comportement alimentaire et comment AA pourrait en être un exemple de dérégulation. 2) Une étude de cohorte a permis de démontrer l’existence de caractéristiques cliniques communes entre addictions et AA et celle d’un probable transfert d’addiction de la nicotine vers l’alimentation. 3) Sur le plan expérimental, nous avons montré qu’il existe des perturbations des ondes P300 et N200, dans l’obésité et la désinhibition alimentaire, proches de celles observées dans les addictions. 4) Enfin, nos résultats suggèrent le rôle potentiel de la ghréline comme marqueur de risque de trouble du comportement alimentaire. Ce travail ouvre des perspectives sur le plan expérimental, avec la suggestion de groupes contrôles plus pertinents ; cliniques, avec la création d’un potentiel test de dépistage rapide ; thérapeutiques, avec la mise en place d’un essai thérapeutique par tDCS / Food addiction (FA) is an old concept, but still subject to controversy. It affects 18 to 24% of obese people. In this thesis, we are interested in overlaps between food behavior regulation, addiction and FA, in order to better understand the mechanisms linked to food intake disinhibition. Our work leads to several results: 1) A review of the literature has shown the existence of close interaction between eating behavior regulation levels and how FA could be an example of their disturbance. 2) A cohort study demonstrated the existence of common clinical features between addiction and FA and a probable addiction transfer from nicotine to food. 3) From an experimental point of view, we have shown that there are disturbances of P300 and N200 ERP, in obesity and food disinhibition, close to those observed in addictions. 4) Finally, our results suggest the potential role of ghrelin as a marker for eating disorders increased risk. This work opens experimental perspectives, with the suggestion of more relevant control groups; clinical perspectives, with the creation of a screening tool; therapeutics perspectives, with the establishment of a therapeutic trial by tDCS

Il apparaît, suite aux résultats de plusieurs études comportementales et d’imagerie cérébrale, que les hormones gonadiques peuvent moduler le fonctionnement cérébral chez la femme. Les asymétries cérébrales fonctionnelles (ACFs), en particulier, changeraient en fonction du niveau de progestérone et d’œstrogène. On a également observé que lorsque le taux d’œstrogène est bas, les performances aux tâches impliquant l’hémisphère droit sont améliorées. Par contre, les preuves de l’action physiologique de ces deux hormones sur le cerveau ne sont pas très nombreuses. Le peu d’études d’électrophysiologie cognitive qui ont porté sur les effets du cycle menstruel ont rapporté que la composante P300 y serait sensible. Aucune n’a cependant utilisé une tâche d’habileté spatiale ou de rotation mentale qui sont connues pour impliquer davantage l’hémisphère droit. Le but de la présente étude est de documenter les changements électrocorticaux reliés aux variations hormonales lors d’une tâche de rotation mentale. Notre hypothèse de départ est que le taux d’œstrogène influencera l’activité électrocorticale et la latéralisation. Les potentiels évoqués cognitifs ont été comparés chez les mêmes femmes (n=12) lors d’une tâche de rotation mentale, répétée à deux périodes du cycle menstruel. Nos résultats démontrent que la condition de rotation induit une latéralisation de l’activité pariétale, vers l’hémisphère gauche, quand le niveau d’œstrogène est bas. Par contre, lorsque le niveau d’œstrogène est élevé, il n’y a aucune latéralisation. Par ailleurs, nous avons observé une augmentation de l’amplitude de la P300 lors du niveau oestrogénique élevé. En conclusion, les fluctuations oestrogéniques du cycle menstruel ont un impact sur la latéralisation de l’activité électrocorticale, lors d’un effort de rotation mentale. / After many behavioral and some neuroimaging studies, it appears that the gonadic hormones can modulate the neuronal function of women's brain. In particular, the functional cerebral asymmetries can be affected by the level of progesterone and estrogens. It has been observed that when the level of estrogen is low, the performance at task that engages more the right hemisphere is enhanced. However, there is a lack of evidence for the physiological actions of these two hormones on the brain. The few event-related potential studies taking into account the menstrual cycle effects, had noticed that the component P300 can be affected. No electrophysiological study has used a mental rotation task or spatial ability tests which are known for their right hemisphere dominance. The aim of the present research is to document the effect of hormonal variations on the electrocortical activity, using a mental rotation task. Our hypothesis is that estrogen levels affect electrocortical activity and lateralization. The ERPs were compared in the same women (n = 12) during a mental rotation task, repeated over two periods of the menstrual cycle. Our results show a lateralization of the left parietal activity when estrogen levels are low and during the rotation. Whereas when the estrogen level is high, there is no lateralization. In addition, we observed an increase in the amplitude of P300 for this same high level. In conclusion, estrogens fluctuations associated with the menstrual cycle have an impact on the lateralization of electrocortical activity, when a mental rotation is needed.

Submitted by Viviane Borim de Goes null (viviane_borim@hotmail.com) on 2018-03-19T11:32:37Z No. of bitstreams: 1 Dissertação_Versão Final_Viviane borim.pdf: 1660097 bytes, checksum: 5a7b7a20f668bfe605743bc3785b11ab (MD5) / Approved for entry into archive by Satie Tagara (satie@marilia.unesp.br) on 2018-03-19T15:00:17Z (GMT) No. of bitstreams: 1 goes_vb_me_mar.pdf: 1660097 bytes, checksum: 5a7b7a20f668bfe605743bc3785b11ab (MD5) / Made available in DSpace on 2018-03-19T15:00:17Z (GMT). No. of bitstreams: 1 goes_vb_me_mar.pdf: 1660097 bytes, checksum: 5a7b7a20f668bfe605743bc3785b11ab (MD5) Previous issue date: 2018-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O processamento da informação auditiva é item fundamental para a função social, de modo a estar envolvido com domínios cognitivos como a função executiva, memória e linguagem. Isso permite ao indivíduo compreensão da linguagem e contribui posteriormente para expressão da mesma durante a comunicação. Nesse mesmo contexto, durante a situação comunicativa, a mesma é modulada pelo organismo por meio do funcionamento do sistema nervoso autônomo. Esse sistema também se relaciona com a cognição e esta, por sua vez, é fundamental para a aquisição e desenvolvimento da linguagem. Em tarefa executiva de linguagem ocorre o envolvimento dos domínios cognitivos acima citados. Dessa maneira, sugere-se que o processamento da informação auditiva se relaciona com o controle autonômico da frequência cardíaca e que tarefa executiva de linguagem pode modificar o desempenho dos potenciais relacionados a evento, de modo a representar maior esforço cognitivo, resultando em menor atividade da modulação parassimpática. Objetivos: Investigar a relação entre os potenciais relacionados a evento e a modulação parassimpática da frequência cardíaca antes e após tarefa executiva de linguagem e verificar os efeitos de tal tarefa. Método: Participaram desta pesquisa 42 mulheres saudáveis entre 18 e 30 anos de idade, com ensino médio completo, divididas em dois grupos: fonológico (n=21) e semântico (n=21). Após a colocação da cinta do cardiofrequencímetro na região do processo xifoide, a voluntária foi orientada a permanecer 10 minutos em repouso, sendo realizado os registros da frequência cardíaca. Em seguida, na primeira fase considerada pré-teste, foi iniciado o registro dos potenciais relacionados a evento com estimulação binaural nos parâmetros de frequência (1KHz/ 2KHz) paradigma oddball, concomitante ao registro da frequência cardíaca. Após, na segunda fase considerada teste, a tarefa executiva de linguagem foi realizada por meio do teste de fluência verbal fonológica para o grupo fonológico e teste de fluência verbal semântica para o grupo semântico. Na terceira fase considerada pós-teste, os registros dos potenciais relacionados a evento e da frequência cardíaca foram realizados utilizando os mesmos protocolos descritos na fase pré-teste. Resultados: Houve correlação da latência de P3 com o índice pNN50 no grupo fonológico pós-teste de fluência verbal fonológica (p=0,036). Na comparação dos potenciais relacionados a evento entre os momentos pré e pós-teste, foi observado diferença média e estatisticamente significante entre a latência de P3 após teste de fluência verbal fonológica, no grupo fonológico (p=0,020). Na comparação da modulação parassimpática da frequência cardíaca entre os momentos repouso, pré e pós-teste, houve diferença entre os índices RMSSD (p=0,007), pNN50 (p=0,035) e SD1 (p=0,007) após teste de fluência verbal fonológica, no grupo fonológico. Conclusão: Houve associação entre os potenciais relacionados a evento com a modulação parassimpática da frequência cardíaca após tarefa executiva de linguagem, em específico o teste de fluência verbal fonológica. Este teste, por sua vez, de forma significante, aumentou a latência de P3 e diminuiu a modulação parassimpática da frequência cardíaca. / The processing of auditory information is a fundamental element for the social function, involved with cognitive domains such as executive function, memory and language. This allows the individual to understand the language and subsequently contributes to its expression during communication. In the same context, during the communicative situation, it is modulated by the organism through the functioning of the autonomic nervous system. This system is also related to cognition and this, in turn, is fundamental for the acquisition and development of language. In the executive task of language, the involvement of the cognitive domains mentioned above occurs. Thus, it is suggested that the auditory information processing is related to the autonomic control of the heart rate and that the executive task of language can modify the performance of the event-related potentials, in order to represent greater cognitive effort, resulting in less activity of the parasympathetic modulation. Objective: To investigate the relationship between event-related potentials and the parasympathetic heart rate modulation before and after language task and verify the effects of such a task. Method: We analyzed 42 healthy women between 18 and 30 years of age with complete high school, were divided into two groups: phonological (n = 21) and semantic (n = 21). After placement of the cardiofrequency measuring strap in the xiphoid process region, the volunteer was instructed to remain at rest for 10 minutes, and heart rate records were performed. Then, in the first phase considered as a pre-test, the event-related potentials with binaural stimulation were started in the frequency parameters (1KHz/ 2KHz) oddball paradigm, concomitant to heart rate recording. After, the second phase, the executive task of language was performed using the phonological verbal fluency test for the phonological group and the semantic verbal fluency test for the semantic group. In the third phase considered post-test, the register the event-related potential and heart rate were performed using the same protocols described in the pre-test phase. Results: There was a correlation between the latency of P3 and the pNN50 index in the phonological group post-test of phonological verbal fluency (p = 0.036). In the comparison of the event-related potentials between the pre- and post-test moments, a mean and statistically significant difference between the P3 latency after phonological verbal fluency test was observed in the phonological group (p = 0.020). There was a difference between the RMSSD (p = 0.007), pNN50 (p = 0.035) and SD1 (p = 0.007) indices in the comparison of the parasympathetic heart rate modulation between the resting, pre and post-test moments phonological verbal fluency, in the phonological group. Conclusion: There was association between the event-related potentials with the parasympathetic heart rate modulation after executive language task, specifically the phonological verbal fluency test. This test, in turn, significantly increased P3 latency and decreased parasympathetic heart rate modulation.

Made available in DSpace on 2016-03-15T19:39:36Z (GMT). No. of bitstreams: 1 Camila Campanha.pdf: 2234537 bytes, checksum: 330a99b6a7ecb7751a711132a17ecb0b (MD5) Previous issue date: 2010-12-14 / Fundo Mackenzie de Pesquisa / Decisions engage careful consideration of the risks and benefits involved in a particular choice. As we live in society, these choices are not only related to our personal interests. Therefore, social interaction has an important role, because the other is part of the context in which we evaluate decisions. Previous studies show the importance of trust and empathy in decision-making processes. In fact, Boudreau, McCubbins and Coulson (2009) showed that trust in another person interferes with behavioral response and also in event related potentials recorded during the test. However, as in other studies, trust was studied by the instruction given to participants that they will base their choices by reports made by another human being - unknown person. The use of an unknown person limits the interpretation of the role of trust involved in decision making processes. Thus this study aims to investigate the decision making processes in a task in which the participant brought to the lab a person (a trusted friend) that act as reporter. In addition, there are few studies investigating event-related potentials in tasks of social decision. Therefore, this study aim to understand the role of trust in decision-making by analysis of behavioral performance in an adapted version of the Ultimatum Game task and also investigate the event related potentials collected simultaneously. Among the main findings, we found a change in the perception of fairness (in fact there was no difference) and, consequently, a change in decision-making with more acceptance of proposals on the condition of interaction with the trusted person than other proposers. Moreover, the P3, FN and LPC potential were modulated by the impact of trust, and by moral internalization, and differed between genders. This study may increase knowledge about the neurobiological bases of behavior and decision making processes involving social interaction, trust and empathy. / Decisões envolvem considerações cuidadosas sobre os riscos e benefícios envolvidos em uma determinada escolha. Por vivermos em sociedade, estas constantes escolhas estão relacionadas não só aos nossos interesses pessoais. Nesse sentido, a interação social tem um importante papel, pois o outro faz parte de um contexto no qual avaliamos possíveis decisões. Estudos prévios mostram a importância da confiança e da empatia em processos de decisão. Nessa direção, Boudreau, McCubbins e Coulson (2009) mostraram que a confiança no outro interfere na resposta comportamental e também nos potenciais cognitivos registrados durante o teste. Entretanto, assim como em outros estudos, a confiança foi estudada pela orientação ao participante de que este estaria sendo orientado por outro ser - humano uma pessoa desconhecida). O uso de uma pessoa desconhecida limita a discussão a respeito do papel da confiança envolvida em processos decisórios. Dessa forma este estudo busca investigar os processos decisórios em uma tarefa na qual o participante levou ao laboratório uma pessoa (amigo de alta confiança) que funcionará como propositor. Além disso, ainda são poucos os estudos investigando potenciais relacionados a evento em tarefa de decisão social. Com isso, este estudo buscou compreender o papel da confiança em processos de decisão analisando o desempenho comportamental em tarefa adaptada do teste Ultimatum Game e também os potenciais cognitivos coletados simultaneamente. Entre os principais achados, encontrou-se uma alteração na percepção de justiça (o que na realidade não havia diferença) e, por conseqüência, uma alteração na tomada de decisão com maior aceite de propostas na condição de interação com a pessoa de confiança em comparação com os outros propositores. Além disso, os potenciais P3, FN e LPC foram modulados pelo impacto da confiança, pela interferência da internalização moral e apresentaram diferenças entre gênero. Este estudo pode aumentar o conhecimento sobre as bases neurobiológicas e comportamentais de processos decisórios envolvendo interação social, confiança e empatia.