Emotionale Gesichtsausdrücke sind hochrelevante Reize für den Menschen. Es wurde daher angenommen, dass sie von evolutionär bedingten Mechanismen automatisch verarbeitet werden. Bis zu welchem Maße diese Verarbeitung tatsächlich automatisch verläuft ist noch immer kontrovers. Die vorliegende Arbeit schließt an diese Debatte an, indem sie eine spontane Tendenz aufzeigt vor allem bedrohlichen Gesichtsaudrücken vermehrt Verarbeitungsressourcen zuzuweisen, auch dann, wenn sie nur oberflächlich enkodiert werden und Emotionalität irrelevant für die gegebene Aufgabe ist (Studie 1 und 2). Diese Tendenz wurde bezüglich zweier Schlüsselkriterien von Automatizität untersucht, nämlich dem Intentionalitäts- (Studie 3) und dem Auslastungskriterium (Studie 4 und 5); diese nehmen an, dass automatische Verarbeitung unabhängig von der gegebenen Intention des Individuums, beziehungsweise konkurrierender Aufgabenanforderungen verläuft. Anhand ereigniskorrelierter Potenziale (EKPs) konnte gezeigt werden, dass verstärkte perzeptuelle Enkodierung emotionaler Gesichtsausdrücke weitgehend unabhängig von Intention auftrat, wohingegen verstärkte höhere kognitive Verarbeitung davon abhing, ob Reize vertieft verarbeitet wurden (Studie 3). Wurde die Kontrolle über die Gesichtsverarbeitung durch eine konkurrierende Aufgabe beeinträchtigt, während Emotionalität relevant war, so verstärkte dies emotionale Effekte auf der perzeptuellen und frühen, höheren kognitiven Ebene (Studie 4). Ähnliches konnte auch für die perzeptuelle Verarbeitung attraktiver Gesichter beobachtet werden (Studie 5). Hingegen war bei verminderter Kontrolle die verstärkte Enkodierung bedrohlicher Ausdrücke in späten kognitiven Verarbeitungsstufen unterdrückt. Die vorliegenden Befunde sprechen gegen eine Automatisierung affektiver Gesichtsverarbeitung und legen stattdessen nahe, dass biologisch vorbereitete Verarbeitungstendenzen durch aufgabenorientierte Kontrollmechanismen und ihr Zusammenspiel mit Intention moduliert werden. / Emotional facial expressions are highly relevant stimuli in humans. It has thus been suggested that they are processed automatically by evolutionarily in-built mechanisms. However, to which extent such processing in fact arises automatically is still controversial. The current work feeds into this debate by showing a tendency to spontaneously allocate increased processing capacity to emotional, especially threat-related expressions, even when processed merely superficially and emotionality is irrelevant to the task at hand (Study 1 and 2). This bias was further tested with regard to key criteria of automaticity; that is the intentionality (Study 3) and the load-insensitivity criterion (Study 4 and 5) assuming automatic processing to arise irrespective of intention of the individual, and concurrent task demands, respectively. Event-related brain potentials (ERPs) revealed enhanced perceptual encoding of threat-related expressions to remain largely unaffected by intention. In contrast, at the higher cognitive level, enhanced encoding depended on whether stimuli were voluntarily processed more deeply (Study 3). However, when control over face processing was impaired by a concurrent task, while emotionality was deemed relevant, emotion effects were enhanced at both, the perceptual and early higher cognitive level (Study 4). Similar was observed for perceptual encoding of attractive faces (Study 5). In contrast, during late higher cognitive stages of in-depth face processing, enhanced encoding of threat was eliminated when control was reduced (Study 4). The present results speak against full automaticity in affective face processing but suggest that biologically prepared processing biases are modulated by task-oriented control mechanisms and their interplay with intention.

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

Ce travail de thèse a été centré sur l’analyse de l’impact d’un système d’alerte anticollision sur le traitement de l’information et le comportement du conducteur en conduite automobile simulée. Les objectifs de ce travail étaient 1) de déterminer l’impact d’un signal avertisseur associé à un système d’alerte anticollision sur le traitement de l’information à partir de potentiels évoqués ; 2) d’analyser l’efficacité d’un tel système en fonction de sa fiabilité ; 3) et en fonction de l’état attentionnel des conducteurs ; et 4) d’examiner l’adaptation comportementale au système au cours du temps. Grâce à une double approche comportementale et électrophysiologique, nous avons montré que le signal avertisseur agit au niveau de l’anticipation et de la préparation à la réponse ainsi qu’au niveau cognitif du traitement de l’information. Par ailleurs, nous avons confirmé que les systèmes anticollision ne nécessitent pas d’être complètement fiables pour être efficaces. Nous avons également observé que l’efficacité du signal avertisseur associé au système anticollision était moindre chez les sujets distraits, notamment lorsque la charge cognitive associée à la distraction était élevée. Ceci suggère que le signal avertisseur nécessite des ressources attentionnelles pour être traité et, donc, pour être efficace. Concernant l’adaptation comportementale au système, les principaux résultats ont montré, d’une part, que l’introduction immédiate du système a eu un effet positif sur le comportement de conduite et, d’autre part, que le processus d’adaptation au système à plus long terme peut être affecté si les conducteurs sont distraits par des tâches secondaires coûteuses en ressources attentionnelles. / This thesis was focused on the analysis of the impact of a collision warning system on information processing and driver behaviour in simulated driving. The objectives of this work were 1) to determine the impact of a warning signal associated with a collision warning system on the processing of information using evoked potentials, 2) to analyse the effectiveness of such a system according to its reliability, 3) and according to the drivers’ attentional state, 4) to examine the behavioural adaptation to the system over time. Using an electrophysiological and behavioural dual approach, we showed that the warning signal acts at the level of anticipation and response preparation and at the level of cognitive processing. Moreover, we confirmed that collision warning systems do not need to be completely reliable to be effective. We also observed that the effectiveness of the warning signal associated with the collision warning system was lower in distracted subjects, especially when the cognitive load associated with the distraction was high. This suggests that the warning signal requires attentionnal resources in order to be processed and, therefore, to be effective. Concerning behavioural adaptation to the system, the main results showed firstly that the immediate introduction of the system had a positive effect on the driving behaviour and secondly that the process of adaptation of the system at the longer term may be affected if drivers are distracted by high demanding secondary tasks.

Introdução: No sistema auditivo, as mudanças decorrentes do envelhecimento resultam na dificuldade que os idosos apresentam em compreender a fala, afetando a capacidade de comunicação e de participação nas relações sociais, podendo levar à piora da qualidade de vida desta população. O treinamento auditivo é uma proposta de intervenção baseada na neuroplasticidade que tem o objetivo de adequar as habilidades auditivas de indivíduos com transtorno do processamento auditivo (TPA). Esse método vem sendo cada vez mais utilizado na reabilitação auditiva de idosos e, por meio de medidas comportamentais e eletrofisiológicas, revela-se como uma ferramenta eficaz para otimizar o processamento da fala, contribuindo para um processo de envelhecimento com qualidade de vida. Objetivos: Verificar a eficácia de um programa de treinamento auditivo acusticamente controlado (TAAC) em idosos com TPA utilizando medidas comportamentais e eletrofisiológicas. Método: Participaram 16 idosos (14 mulheres, dois homens) com TPA, os quais realizaram uma avaliação inicial (avaliação 1), composta por testes comportamentais e eletrofisiológicos do processamento auditivo, e foram distribuídos em dois grupos: GP (n=8), submetidos a um treinamento placebo e GSI (n=8) que não foram submetidos a nenhuma intervenção. Após 12 semanas os indivíduos foram submetidos novamente aos testes (avaliação 2 - pré TAAC). Em seguida, todos os indivíduos foram submetidos ao TAAC e após 12 semanas realizaram a avaliação final (avaliação 3 - pós TAAC). Resultados: Não houve diferença significante na análise multivariada entre as avaliações 1 e 2, tanto para os testes comportamentais quanto para o P300, sendo descartada a ocorrência de efeito placebo e efeitos teste-reteste. Na comparação entre as avaliações 2 e 3, foi constatada melhora significante entre as condições pré TAAC e pós TAAC para a maioria das habilidades auditivas investigadas pelo método comportamental; entretanto, o mesmo resultado não foi encontrado para os parâmetros do P300 em nenhuma das condições (tone burst ou fala). Também não foi encontrada diferença significante entre o P300 evocado por estímulo tone burst e o evocado por estímulo de fala no monitoramento das mudanças neurobiológicas decorrentes do TAAC. Conclusões: O TAAC foi capaz de promover uma mudança no desempenho comportamental dos idosos para a maioria das habilidades auditivas investigadas, mostrando ser um método eficaz na reabilitação auditiva de idosos com TPA. Considerando a grande vulnerabilidade aos fatores cognitivos e a variabilidade intra-sujeito que o P300 apresenta, concluímos que este potencial não parece ser a melhor ferramenta para monitorar as mudanças decorrentes do programa TAAC em idosos / Introduction: In the hearing system, changes from aging result in the difficulty that the elderly have understanding speech, affecting their communication abilities and their social participation in the community, which can lead to a decrease of life quality in this group of people. The auditory training is an intervention procedure based on neuroplasticity that aims improving hearing abilities of individuals with auditory processing disorder (APD). This method has been used in the auditory rehab of elderly and, through behavioral and electrophysiological measures, reveals itself as an effective tool for optimizing the processing of speech contributing for an aging process with life quality. Purpose: Verify the efficacy of an acoustically controlled auditory training program (ACAT) in elderly patients with APD using behavioral and electrophysiological measures. Method: Sixteen elderly (14 women, two men) with APD, who have performed an initial evaluation (1), consisting of behavioral and electrophysiological tests of auditory processing, were divided into two groups: GP (n = 8) those who were submitted to a placebo training and GSI (n = 8) the one\'s not submitted to any intervention. After 12 weeks the individuals were submitted to the tests again (evaluation 2 - pre ACAT). Then, all of them were submitted to ACAT and, after 12 weeks (8 training), they were submitted to the final evaluation (3 - post ACAT). Results: There was no significant difference in the various analyses between evaluations 1 and 2, both in the behavioral tests as for the P300, discarding the presence of placebo effects and test-retest. Comparing the evaluations 2 and 3, a significant improvement was found between the pre and post ACAT conditions for the majority of the auditory abilities investigated by the behavioral method; however, the same result was not found for the parameters of P300 in any of the conditions (tone burst or speech). The same way, no significant difference was found between the P300 evoked by tone burst and evoked by speech stimulation during the neurobiological changes monitoring coming from ACAT. Conclusions: The ACAT was able to promote a change in the behavioral performance of the elderly for most investigated auditory abilities, proving to be an effective method regards hearing rehabilitation of elderly with APD. Considering the high vulnerability to the cognitive factors and intra-subject variability that the P300 presents, we conclude that this potential does not seem to be the best tool to monitor the changes that result from the ACAT program in the elderly

Introdução: Plasticidade auditiva refere-se a mudanças que ocorrem no sistema sensorial responsável pela transmissão da informação acústica. A plasticidade do sistema nervoso auditivo central está relacionada a capacidade de adaptação através da reintrodução de estímulos por meio de aparelhos de amplificação sonora ou implante coclear. Essas mudanças são observadas a partir do desempenho de pacientes com o uso do aparelho de amplificação sonora, e podem ser verificadas por meio dos potenciais evocados auditivos de longa latência. Objetivo: caracterizar os Potenciais Evocados Auditivos de Longa Latência (PEALL) em adultos e idosos com perda auditiva neurossensorial, verificando os efeitos da estimulação auditiva por meio da comparação destes potenciais pré e pós adaptação do Aparelho de Amplificação Sonora Individual (AASI). Metodologia: Participaram deste estudo 15 indivíduos adultos e idosos, de ambos os gêneros, de 55 a 85 anos de idade, com perda auditiva neurossensorial de grau leve a moderado com simetria entre as orelhas, sem experiência prévia com qualquer tipo de dispositivo de amplificação sonora. Os indivíduos foram encaminhados pelas empresas de aparelho auditivo WIDEX, Audibel e o Espaço Reouvir, tratando-se de novos usuários de AASI. Os PEALL foram realizados nas condições com e sem AASI, a 60 e 75 dBnNA em campo sonoro, em dois momentos: primeira avaliação realizada até uma semana após a adaptação do AASI e a segunda avaliação realizada após 6 meses da adaptação do AASI. Resultados: Na comparação da primeira avaliação com a segunda avaliação, na condição sem AASI a 60 dBnNA, observou-se diferença estatisticamente significante na latência do componente P1 (p-valor= 0,034). Na condição sem AASI a 75 dBnNA, observou-se diferença estatisticamente significante para a latência do componente P300 (p-valor 0,031) e para a amplitude P2N2 (p-valor 0,024), com diminuição da latência e aumento da amplitude na segunda avaliação. Por sua vez, na comparação da primeira avaliação com a segunda avaliação, na condição com AASI a 75 dBnNA, obteve-se uma diferença estatisticamente significante na latência do componente N2 (p-valor 0,009) e na amplitude P2N2 (p-valor 0,024), com aumento da amplitude na segunda avaliação. Evidenciou-se, também, diferença significante na amplitude P1N1 (p-valor 0,024) na condição com AASI a 60 dBnNA. Conclusão: Os PEALL com estímulo de fala demonstraram ser um importante procedimento para ser utilizado na prática clínica, visando monitorar a plasticidade neuronal do Sistema Nervoso Auditivo Central frente à estimulação auditiva (uso de AASI), em adultos e idosos com perda auditiva neurossensorial de grau leve a moderado / Introduction: Auditory plasticity refers to changes that occur in the sensory system responsible for the transmission of acoustic information. The plasticity of the central auditory nervous system is related to the capacity of adaptation through the reintroduction of stimuli of sound amplification devices or cochlear implants. These changes are observed from the performance of patients with the use of the sound amplification apparatus, and can be verified by long-latency auditory evoked potentials. Purpose: To characterize long latency auditory evoked potentials (LLAEP) in adults with sensorineural hearing loss, verifying the effects of auditory stimulation by comparing these before and after adaptation potentials of the Individual Sound Amplification (AASI). Methodology: Fifteen adult and elderly individuals of both genders, aged 55 to 85 years, with mild to moderate sensorineural hearing loss with symmetry between the ears, without prior experience with any type of sound amplification device. The subjects were referred by hearing aid companies WIDEX, Audibel and Espaço Reouvir, in the case of new hearing aids users. The LLAEP were performed in the conditions with and without AASI, at 60 and 75 dBnNA in sound field, in two moments: first evaluation performed up to one week after AASI adaptation and the second evaluation performed after 6 months of AASI adaptation. Results: In the comparison of the first evaluation with the second evaluation, in the condition without AASI at 60 dBnNA, a statistically significant difference was observed in the latency of the P1 component (p-value = 0.034). In the condition without AASI at 75 dBnNA, a statistically significant difference was observed for the latency of the P300 component (p-value 0.031) and for the P2N2 amplitude (p-value 0.024), with latency decrease and amplitude increase in the second evaluation. In the comparison of the first evaluation with the second evaluation, in the condition with AASI at 75 dBnNA, there was a statistically significant difference in the latency of the N2 component (p-value 0.009) and in the P2N2 amplitude (p-value 0.024) , With amplitude increase in the second evaluation. There was also a significant difference in P1N1 amplitude (p-value 0.024) in the condition with AASI at 60 dBnNA. Conclusion: The LLAEP was an important procedure to be used in clinical practice, aiming to monitor the neural plasticity of the Central Auditory Nervous System in front of auditory stimulation (hearing aids use) in adults and elderly patients with mild to moderate sensorineural hearing loss of amplification and the importance of neural plasticity of the Central Auditory Nervous System

INTRODUÇÃO: A Esclerose Múltipla é uma doença desmielinizante e autoimune, na qual ocorre a destruição da bainha de mielina por autoanticorpos. Esta destruição causa uma diminuição na velocidade de condução do impulso nervoso alterando, assim, as funções cerebral e neural. Para ocorrer o funcionamento adequado do sistema auditivo, tanto na sua porção periférica quanto na central há necessidade que o mesmo esteja íntegro. OBJETIVO: Este estudo tem como objetivo verificar a ocorrência de alterações nos potenciais evocados auditivos de curta (PEATE), média (PEAML) e longa (P300) latências em adultos audiologicamente normais com diagnóstico de Esclerose Múltipla do tipo remitente recorrente ou surto remissivo. MÉTODO: Para o grupo controle foram avaliados 25 indivíduos com histórico de desenvolvimento neurológico normal e sem queixa de zumbido, sendo 19 do gênero feminino e seis do masculino, com idade variando entre 25 e 55 anos (média de 35,16 anos de idade). Para o grupo pesquisa foram avaliados 25 indivíduos com Esclerose Múltipla do tipo remitente-recorrente ou surto-remissivo, seis do gênero masculino e 19 do feminino, com idades entre 25 e 53 anos (média de 34,88 anos de idade). Todos os indivíduos participantes da pesquisa realizaram audiometria tonal e vocal, medidas de imitância acústica e os potenciais evocados auditivos de curta, média e longa latências. RESULTADOS: Os resultados demonstraram ocorrência de alterações nos potenciais evocados auditivos de tronco encefálico e de média latência e no potencial cognitivo, em indivíduos com Esclerose Múltipla. Com relação ao potencial evocado auditivo de tronco encefálico, verificou-se aumento de latência das ondas III e V e dos interpicos I-III e I-V, sugerindo alteração de tronco encefálico baixo. No que diz respeito ao potencial evocado auditivo de média latência observou-se atraso nas latências das ondas Na e Pa e, para o potencial cognitivo, evidenciou-se aumento da latência do P300. Conclusão: Indivíduos com Esclerose Múltipla do tipo remitente recorrente apresentam alterações eletrofisiológicas observadas nos resultados dos potenciais evocados auditivos de curta e média latências e no potencial cognitivo, sugerindo comprometimento em diferentes locais do sistema nervoso auditivo central / INTRODUCTION: The Multiple Sclerosis is a demyelinating disease and autoimmune, which is the destruction of the myelin sheath of a selfantibodies. This destruction causes a decrease in impulse driving speed of nervous changing thus the brain and neural functions. To place the proper functioning of the auditory system, both in its peripheral portion as the central need that it is full. PURPOSE: This study aims to determine the occurrency of changes in auditory evoked potentials of short (PEATE), middle (PEAML) and long (P300) latencies in adults audiologically normal diagnosed with Multiple Sclerosis remitting type of applicant or remissive outbreak. METHOD: For the control group were evaluated 25 individuals with a history of normal neurological development and without complaint from tinnitus, and 19 females and six males, with ages ranging between 25 and 55 years (average of 35.16 years of age) . To search the group were evaluated 25 individuals with Multiple Sclerosis-remitting type of applicant or flareremissive, six males and 19 females, aged between 25 and 53 years (average of 34.88 years of age). All individuals participating in the search conducted tone audiometry and speech, acoustic immitance measures brainstem auditory evoked potential, middle latency response and cognitive potential RESULTS: The results showed occurrencies of changes in brainstem auditory evoked potential and middle latency and cognitive potential in individuals with Multiple Sclerosis. Regarding the potential of brain stem auditory evoked, there was an increase in latency wave III and V and interpeaks I-III and IV, suggesting change in brainstem down. Regarding the auditory evoked potential of average latency there was delay in latencies of Na and Pa waves, and the potential for cognitive, showed an increase of latency of P300. Conclusion: Individuals with multiple sclerosis relapsing remitting type of applicant presents electrophysiological changes seen in the results of sound evoked short and middle latency and the potential cognitive suggesting impairment from different parts of the central auditory nervous system

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.

Introdução: Plasticidade auditiva refere-se a mudanças que ocorrem no sistema sensorial responsável pela transmissão da informação acústica. A plasticidade do sistema nervoso auditivo central está relacionada a capacidade de adaptação através da reintrodução de estímulos por meio de aparelhos de amplificação sonora ou implante coclear. Essas mudanças são observadas a partir do desempenho de pacientes com o uso do aparelho de amplificação sonora, e podem ser verificadas por meio dos potenciais evocados auditivos de longa latência. Objetivo: caracterizar os Potenciais Evocados Auditivos de Longa Latência (PEALL) em adultos e idosos com perda auditiva neurossensorial, verificando os efeitos da estimulação auditiva por meio da comparação destes potenciais pré e pós adaptação do Aparelho de Amplificação Sonora Individual (AASI). Metodologia: Participaram deste estudo 15 indivíduos adultos e idosos, de ambos os gêneros, de 55 a 85 anos de idade, com perda auditiva neurossensorial de grau leve a moderado com simetria entre as orelhas, sem experiência prévia com qualquer tipo de dispositivo de amplificação sonora. Os indivíduos foram encaminhados pelas empresas de aparelho auditivo WIDEX, Audibel e o Espaço Reouvir, tratando-se de novos usuários de AASI. Os PEALL foram realizados nas condições com e sem AASI, a 60 e 75 dBnNA em campo sonoro, em dois momentos: primeira avaliação realizada até uma semana após a adaptação do AASI e a segunda avaliação realizada após 6 meses da adaptação do AASI. Resultados: Na comparação da primeira avaliação com a segunda avaliação, na condição sem AASI a 60 dBnNA, observou-se diferença estatisticamente significante na latência do componente P1 (p-valor= 0,034). Na condição sem AASI a 75 dBnNA, observou-se diferença estatisticamente significante para a latência do componente P300 (p-valor 0,031) e para a amplitude P2N2 (p-valor 0,024), com diminuição da latência e aumento da amplitude na segunda avaliação. Por sua vez, na comparação da primeira avaliação com a segunda avaliação, na condição com AASI a 75 dBnNA, obteve-se uma diferença estatisticamente significante na latência do componente N2 (p-valor 0,009) e na amplitude P2N2 (p-valor 0,024), com aumento da amplitude na segunda avaliação. Evidenciou-se, também, diferença significante na amplitude P1N1 (p-valor 0,024) na condição com AASI a 60 dBnNA. Conclusão: Os PEALL com estímulo de fala demonstraram ser um importante procedimento para ser utilizado na prática clínica, visando monitorar a plasticidade neuronal do Sistema Nervoso Auditivo Central frente à estimulação auditiva (uso de AASI), em adultos e idosos com perda auditiva neurossensorial de grau leve a moderado / Introduction: Auditory plasticity refers to changes that occur in the sensory system responsible for the transmission of acoustic information. The plasticity of the central auditory nervous system is related to the capacity of adaptation through the reintroduction of stimuli of sound amplification devices or cochlear implants. These changes are observed from the performance of patients with the use of the sound amplification apparatus, and can be verified by long-latency auditory evoked potentials. Purpose: To characterize long latency auditory evoked potentials (LLAEP) in adults with sensorineural hearing loss, verifying the effects of auditory stimulation by comparing these before and after adaptation potentials of the Individual Sound Amplification (AASI). Methodology: Fifteen adult and elderly individuals of both genders, aged 55 to 85 years, with mild to moderate sensorineural hearing loss with symmetry between the ears, without prior experience with any type of sound amplification device. The subjects were referred by hearing aid companies WIDEX, Audibel and Espaço Reouvir, in the case of new hearing aids users. The LLAEP were performed in the conditions with and without AASI, at 60 and 75 dBnNA in sound field, in two moments: first evaluation performed up to one week after AASI adaptation and the second evaluation performed after 6 months of AASI adaptation. Results: In the comparison of the first evaluation with the second evaluation, in the condition without AASI at 60 dBnNA, a statistically significant difference was observed in the latency of the P1 component (p-value = 0.034). In the condition without AASI at 75 dBnNA, a statistically significant difference was observed for the latency of the P300 component (p-value 0.031) and for the P2N2 amplitude (p-value 0.024), with latency decrease and amplitude increase in the second evaluation. In the comparison of the first evaluation with the second evaluation, in the condition with AASI at 75 dBnNA, there was a statistically significant difference in the latency of the N2 component (p-value 0.009) and in the P2N2 amplitude (p-value 0.024) , With amplitude increase in the second evaluation. There was also a significant difference in P1N1 amplitude (p-value 0.024) in the condition with AASI at 60 dBnNA. Conclusion: The LLAEP was an important procedure to be used in clinical practice, aiming to monitor the neural plasticity of the Central Auditory Nervous System in front of auditory stimulation (hearing aids use) in adults and elderly patients with mild to moderate sensorineural hearing loss of amplification and the importance of neural plasticity of the Central Auditory Nervous System

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