O altruísmo é um importante constructo comportamental envolvido nas relações sociais; mesmo que aparentemente não haja ganho imediato em ações altruístas, o objetivo de favorecer o progresso do grupo e da sociedade resulta no beneficiamento do próprio agente. Objetivos são mais facilmente alcançados com a ajuda de outros, ao mesmo tempo que há melhora na qualidade das relações sociais. Alguns fatores influenciam o comportamento altruísta, o estresse é um deles; a indução aguda de estresse pode ser eficiente em verificar comportamentos a curto prazo em laboratório, apesar de não haver consenso de que maneira este modifica as intenções de ajuda e o comportamento prósocial. O estresse também pode influenciar a maneira como avaliamos a distribuição de dinheiro ou bens feita por outrem: percepção de justiça. O Jogo do Ditador mostrase eficiente para analisar altruísmo e percepção de justiça, assim como o cortisol salivar se mostra capaz em auxiliar a análise do estresse agudo. Este trabalho avaliou em 94 estudantes universitários, de diversos cursos da Universidade Federal do Rio Grande do Sul, se a indução de estresse agudo via tarefa de estresse social (T rier Social Stress Task ) relacionase a comportamentos altruístas e maior avaliação negativa para divisões injustas de dinheiro em dois jogos do ditador computadorizados a interação em ambos foi com desconhecidos. Os grupos foram divididos em dois sexos e em duas condições: experimental estresse e controle placebo. O dinheiro fictício usado para jogar foi ganho em uma tarefa de planejamento, executada em seguida da indução de estresse. Este foi mensurado por duas medidas fisiológicas: batimentos cardíacos e coleta de saliva para análise de cortisol; e por resposta de autoavaliação de ansiedade; as sessões duraram 60 minutos. Não foram encontradas correlações entre medidas fisiológicas e tomada de decisão egoísta, entretanto, encontrouse diferenças estatísticas significativas comportamentais entre os grupos: mulheres do grupo de controle são mais altruístas, quando dividem montantes mais altos de dinheiro; o grupo experimental avaliou como mais injustas ofertas egoístas (menor parte para ele(a)) do montante mais baixo e também como menos injustas ofertas altruístas (maior parte para ele(a)) do montante mais alto; os grupos também diferiram significativamente na oferta de divisão feita a desconhecidos; ademais, o grupo experimental levou mais tempo para iniciar a tarefa de planejamento do que o controle para ambos sexos. Concluise que medidas fisiológicas não se relacionam aos resultados pósestresse, porém diferenças comportamentais podem ser analisadas. Inferese que mulheres tem comportamentos mais altruístas por influência cultural. Percepção de justiça aumentada, comportamento egoísta e aumento do tempo de preparação na tarefa de planejamento podem ser o resultado do aumento da carga cognitiva por efeito da indução de estresse. / Altruism is an important behavioral construct in social relations; even though it appears to be no immediate gain in selfless actions. The purpose of promoting the group's and society’s progress results in the agent's own benefit. Goals are more easily achieved with the help of others, while there is improvement in the quality of social relations. Some factors have influence in altruistic behavior, stress is one of them; inducing acute stress can be effective in checking behaviors in imediate reaction in the laboratory, although there is no consensus on how this modifies intentions to help others and prosocial behavior. Stress can also influence how we evaluate the distribution of cash or goods made by others: perception of justice. The Dictator Game proves efficient to analize altruism and sense of justice, and salivary cortisol has shown able to assist in the analysis of acute stress. This study evaluated the impact of acute stress induction on 94 university students of different graduation courses of the Federal University of Rio Grande do Sul. Acute stress was induced via social stress task (Trier Social Stress Task) to identify if it relates to altruistic behavior and the negative assessment to unfair money distribution in two computerized dictator games. The subjects in both games were unknown to each other. Subjects were divided by sex and than two groups: experimental stress condition and control placebo condition. The fictitious money used to play was won in a planning task, followed by the stress induction. The impact was measured by two physiological metrics: heart rate and saliva collection for cortisol analysis; and the selfassessment test of anxiety. Each individual sessions lasted 60 minutes. Correlations between physiological measurements and the making of selfish decision were not found. However, significant statistical behaviors differences were found between: the control group of women who were more altruistic when dividing larger amounts of money; t he experimental group evaluated selfish money offers as more unfair in the lower cash amount experiment (lower share for him/her). We also found as less unfair the altruistic offers made on the experiment’s larger cash amount (highest share for him/her). The groups also differ significantly in the division of money made to unknown individuals; in addition, the experimental group took longer to start the planning task than the control group for both sexes. We conclude that physiological measures are not related to poststress results, but behavioral differences can be analyzed. It appears that women tend to be more altruistic because of cultural influence. Increased perception of justice, selfish behavior and longer time taking to plan the planning task can be the result of increased cognitive overload as a result of induction of stress.

Because of the impact of stress on health, it is important to understand the variables that underlie cardiovascular reactivity to stress because it may lead to more focused targets of intervention for helping people to reduce or otherwise better manage their stress. The purpose of the present study was to answer the following questions: does lack of eudaimonic well-being (a combination of psychological and social well-being) predict increased cardiovascular reactivity to stress in a clinically distressed population? And does increased eudaimonic well-being protect against increased cardiovascular reactivity to stress when hedonic well-being (a combination of positive affect and life satisfaction) is low and depression and stress are high? If so, then it may be possible to reduce the effects of stress on health even if depression and stress are present. One hundred twenty-nine college students (ages 18-29) who were clinically distressed were administered a questionnaire that included questions about demographic variables and measures of hedonic and eudaimonic well-being, depression, and general perceived stress. After answering the questionnaire, a baseline reading of cardiovascular activity was taken. After the baseline reading, participants were subjected to the Trier Social Stress Test (TSST), an interpersonal stressor that consists of an anticipation period, a speech, and a math task. Measurements of cardiovascular activity were taken throughout the TSST. I predicted that lower levels of eudaimonic and hedonic well-being, mental health, and higher amounts of general perceived stress would predict increased cardiovascular reactivity to the TSST as measured by systolic blood pressure, diastolic blood pressure, and heart rate. Then, should the prior hypothesis be true, I predicted that higher eudaimonic well-being will suppress the effect of lower hedonic will-being, lower mental health, and higher general perceived stress on cardiovascular activity to acute stress. Results of the study found no effect of eudaimonic well-being, hedonic well-being, depression, and general perceived stress on cardiovascular reactivity during the TSST. The results suggest that there is no relationship between well-being, depression, and general perceived stress and cardiovascular reactivity to stress in a young college student population.

The physiological responses to stressor exposure can be broadly grouped into the organismal and the cellular stress responses. The organismal stress response involves the release of hormones into general circulation, while the cellular stress response involves the synthesis of proteins, the most important being the heat shock proteins (HSPs), which play a role in maintaining protein homeostasis. Elevated HSP70 expression in response to stressors has been demonstrated in trout (Oncorhynchus mykiss) red blood cells (RBCs). The ease of repeated sampling of blood suggests the possibility of using this tissue as a non-lethal marker of cellular stress in fish. This study tested the hypothesis that stressor exposure will elevate HSP70 expression in trout RBCs and the role of stress hormones in mediating this response. Acute heat shock exposure (+12oC) significantly elevated plasma cortisol, glucose and lactate levels in heat shocked fish over 24 h. A tissue-specific response was seen in HSP70 expression in liver, brain, gill and RBCs. To enable measurement of RBC HSP70 concentrations, an enzyme-linked immunosorbent assay (ELISA) was developed using a commercially available rabbit anti-salmon HSP70 and a recombinant chinook salmon (Oncorhynchus tshawytscha) HSP70. To determine effects of chronic exposure, two studies were conducted exposing trout to either cadmium (0, 0.75 or 2.0 µg/L over 28 d) or municipal wastewater effluent (0, 20 or 90% over 14 d). However, neither exposure elicited a significant HSP70 response. Effects of stress hormones on RBC HSP70 levels were tested by exposing cells in vitro to either cortisol (10 and 100 ng/mL) or epinephrine (10 nM) with or without heat shock. Heat shock elevated HSP70 content in trout RBCs but no modulation by stress hormones was seen. It was shown for the first time that RBCs release HSP70 content into the medium in response to an acute heat shock and this release is attenuated by stress hormones. Overall, HSP70 levels in RBCs have the potential to be a reliable non-lethal marker of acute cellular stress effects in fish. The release of HSP70 from RBCs leads to the hypothesis that HSP70 may also have an extracellular role in fish, and warrants further study.

The physiological responses to stressor exposure can be broadly grouped into the organismal and the cellular stress responses. The organismal stress response involves the release of hormones into general circulation, while the cellular stress response involves the synthesis of proteins, the most important being the heat shock proteins (HSPs), which play a role in maintaining protein homeostasis. Elevated HSP70 expression in response to stressors has been demonstrated in trout (Oncorhynchus mykiss) red blood cells (RBCs). The ease of repeated sampling of blood suggests the possibility of using this tissue as a non-lethal marker of cellular stress in fish. This study tested the hypothesis that stressor exposure will elevate HSP70 expression in trout RBCs and the role of stress hormones in mediating this response. Acute heat shock exposure (+12oC) significantly elevated plasma cortisol, glucose and lactate levels in heat shocked fish over 24 h. A tissue-specific response was seen in HSP70 expression in liver, brain, gill and RBCs. To enable measurement of RBC HSP70 concentrations, an enzyme-linked immunosorbent assay (ELISA) was developed using a commercially available rabbit anti-salmon HSP70 and a recombinant chinook salmon (Oncorhynchus tshawytscha) HSP70. To determine effects of chronic exposure, two studies were conducted exposing trout to either cadmium (0, 0.75 or 2.0 µg/L over 28 d) or municipal wastewater effluent (0, 20 or 90% over 14 d). However, neither exposure elicited a significant HSP70 response. Effects of stress hormones on RBC HSP70 levels were tested by exposing cells in vitro to either cortisol (10 and 100 ng/mL) or epinephrine (10 nM) with or without heat shock. Heat shock elevated HSP70 content in trout RBCs but no modulation by stress hormones was seen. It was shown for the first time that RBCs release HSP70 content into the medium in response to an acute heat shock and this release is attenuated by stress hormones. Overall, HSP70 levels in RBCs have the potential to be a reliable non-lethal marker of acute cellular stress effects in fish. The release of HSP70 from RBCs leads to the hypothesis that HSP70 may also have an extracellular role in fish, and warrants further study.

L'intégration du facteur "stress aigu" dans les problématiques de Management des Hommes équivaut à revisiter les apports et théories des Sciences de Gestion, à réinterroger et à apporter un éclairage nouveau sur des concepts fondamentaux du Management. Ainsi, il apparait que la performance et la capacité de restitution des compétences acquises par les individus dépendent directement de leur niveau de stress. En effet, en fonction du déséquilibre entre la perception qu'une personne a des contraintes que lui impose son environnement et la perception qu'elle a de ses propres ressources pour y faire face, il est possible que la dose de stress générée permette une optimisation de son comportement ou a contrario inhibe ses capacités. A ce titre, les managers doivent se préparer à savoir gérer la crise non seulement aux niveaux techniques et organisationnels mais également en prenant en compte les dimensions comportementales et psychologiques, dont le facteur "stress aigu". Ils doivent également avoir présent à l'esprit que la crise peut impacter leur propre psychologie mais également celles de leurs collaborateurs. Pour l'ensemble de ces raisons, le "stress aigu" est un des éléments fondamentaux à prendre en compte pour les auteurs qui s'intéressent aux problématiques de gestion de crise, de résilience et de fiabilité organisationnelle. / The integration of the "acute stress" factor in the problems of Human Management entails revisiting contributions and theories of Management Sciences, reexamining and shedding new light on fundamental concepts of Management. Thus, it appears that the performance and the capacity of restitution of skills acquired by individuals, depends directly on their level of stress. In fact, depending on the imbalance between the perception that a person has of the constraints imposed by his environment and the perception that he bas of his own resources in order to face them, it is possible that the level of stress generated allows an optimization of his behavior or in contrast, inhibits his abilities. Therefore, managers must be prepared to manage the crisis not only at technical and organizational levels, but also by taking into account the behavioral and psychological dimensions, including the "acute stress" factor. They must also bear in mind that the crisis can affect their own behavior as well as their colleague's behavior. For all these reasons, "acute stress" is one of the fundamental elements to be taken into account for authors who are interested in issues of crisis management, resilience and organizational reliability.

O Transtorno de Estresse Agudo (TEA) reúne o conjunto dos sintomas presentes nos indivíduos diante exposição a um evento traumático. A maneira como os indivíduos enfrentam os acontecimentos da vida está relacionada a vários fatores como as características de personalidade e ao estilo defensivo, ambos com uma importante influência no momento pós-trauma. O objetivo desta investigação foi pesquisar as caracteristicas de personalidade e o estilo defensivo em pacientes que sofreram trauma físico e desenvolveram TEA. O delinemeanto utilizado foi um estudo transversal controlado. A amostra foi por conveniência, composta por 18 pacientes com TEA e 42 pacientes sem TEA que sofreram trauma físico e necessitaram de internação em um Hospital referência em trauma em Porto Alegre, Rio Grande do Sul, Brasil. Os instrumentos utilizados foram um questionário estruturado, entrevista clínica, questionário de nível sócio econômico (NSE), questionário de Estilo Defensivo (DSQ), Bateria Fatorial de Peronalidade (BFP) e “The Mini-International Neuropsychiatric Interview” (M.I.N.I.). Resultados: Os dois grupos apresentarm uma distribuição homogênea em relação às variáveis clínicas e demográficas. Indivíduos com TEA apresentaram médias elevadas no fator de Neuroticismo da Bateria Fatorial de Personalidade, bem como nas sub-facetas de vulnerabilidade, instabilidade emocional e depressão. Em relação aos mecanismos defensivos foi demonstrado que a projeção, a agressão passiva, a atuação, o deslocamento, a cisão e a somatização podem estar relacionados a uma maior chance para o desenvolvimento de transtorno de estresse agudo em vítimas de trauma físico. Nesta amostra, os pacientes que desenvolveram transtorno de estresse agudo utilizaram mecanismos de defesas mais primitivos quando comparados aos indivíduos que não desenvolveram TEA. Além disso, são pessoas mais instáveis emocionalmente, apresentando um padrão de comportamento negativo em relação aos eventos cotidianos. / The Acute Stress Disorder (ASD) covers all the symptoms present in individuals before exposure to a traumatic event. The way individuals face the events of life is related to several factors such as personality characteristics and defensive style, both with an important influence in the post traumatic moment. The purpose of this research is to investigate the personality characteristics and defensive style in patients who have suffered physical trauma and developed ASD. The delimitation used was a controlled cross-sectional study. A convenience sample was used, consisting of 18 patients with ASD and 42 healthy who have suffered physical trauma and required admission to a referral hospital in trauma in Porto Alegre, Rio Grande do Sul, Brazil. The instruments used were a structured questionnaire, clinical interview, questionnaire (NSE), Defensive Style Questionnaire (DSQ), Factorial Personality Battery (BFP) and The Mini-International Neuropsychiatric Interview (MINI). Results: The two groups presented a homogeneous distribution in relation to clinical and demographic variables. Individuals with ASD had a high average in Neuroticism factor of Personality Factor Battery and the vulnerability of sub-facets, emotional instability and depression. In relation to the defensive mechanisms it has been shown that the projection, passive aggression, acting, displacement, division and somatization may be related to a greater chance for the development of acute stress disorder in physical trauma. In this sample, patients who developed acute stress disorder used more primitive defense mechanisms when compared to the patients without acute stress disorder. Besides that, they are more emotionally unstable people, having a negative pattern of behavior in relation to the daily events.

Currently, low back disorder (LBD) research focuses primarily on mechanical variables to assess whether acute or cumulative task demands exceed the capacity of the tissue; however, it is important to assess how other non-mechanical variables affect tissue capacity in a time-dependent manner. The current investigation sought to explore physiological responses to an acute lifting task (similar to a typical assembly line task), as lifting has been implicated as a risk factor in the development of LBDs. Twelve participants completed two experimental sessions of two hours of repetitive symmetrical lifting from floor to knuckle height under a low force, high repetition condition (LFHR; box weighted at 5% maximum lifting strength, five lifts per minute) and a high force, low repetition condition (HFLR; 25% maximum lifting strength, one lift per minute), such that the external biomechanical work was equivalent between conditions. These sessions were completed one week apart, with full-body motion capture and ground reaction forces measured throughout. Systemic inflammation was assessed with blood sampling at baseline, 0, 4 and 24 hours post-lifting on both days, and samples were assayed using an ELISA for interleukin 6 (IL-6) and interleukin 8 (IL-8). Participants also completed psychological questionnaires including the Tampa Scale for Kinesiophobia-General (TSK-G), Pain Catastrophizing Scale, Visual Analogue Scale (VAS, participants 1-4) and Borg CR-10 Scale of Exertion (participants 5-12). There was a significant main effect of time on both IL-6 and IL-8 (Baseline, 0, 4, 24 hours), as well as interaction effects of condition (HFLR and LFHR) and time. The LFHR condition caused greater inflammation in both IL-6 and IL-8 at 0 and 4 hours post-lifting, likely due to significantly higher cumulative spinal loading in this condition. Significant correlations between body fat percentages, peak and cumulative loading were found to exist in both the LFHR condition and the HFLR condition, lending strength to the hypothesis that some of these measures may be able to predict physiological responses to acute stresses, and subsequently, risk of acute injury.

O altruísmo é um importante constructo comportamental envolvido nas relações sociais; mesmo que aparentemente não haja ganho imediato em ações altruístas, o objetivo de favorecer o progresso do grupo e da sociedade resulta no beneficiamento do próprio agente. Objetivos são mais facilmente alcançados com a ajuda de outros, ao mesmo tempo que há melhora na qualidade das relações sociais. Alguns fatores influenciam o comportamento altruísta, o estresse é um deles; a indução aguda de estresse pode ser eficiente em verificar comportamentos a curto prazo em laboratório, apesar de não haver consenso de que maneira este modifica as intenções de ajuda e o comportamento prósocial. O estresse também pode influenciar a maneira como avaliamos a distribuição de dinheiro ou bens feita por outrem: percepção de justiça. O Jogo do Ditador mostrase eficiente para analisar altruísmo e percepção de justiça, assim como o cortisol salivar se mostra capaz em auxiliar a análise do estresse agudo. Este trabalho avaliou em 94 estudantes universitários, de diversos cursos da Universidade Federal do Rio Grande do Sul, se a indução de estresse agudo via tarefa de estresse social (T rier Social Stress Task ) relacionase a comportamentos altruístas e maior avaliação negativa para divisões injustas de dinheiro em dois jogos do ditador computadorizados a interação em ambos foi com desconhecidos. Os grupos foram divididos em dois sexos e em duas condições: experimental estresse e controle placebo. O dinheiro fictício usado para jogar foi ganho em uma tarefa de planejamento, executada em seguida da indução de estresse. Este foi mensurado por duas medidas fisiológicas: batimentos cardíacos e coleta de saliva para análise de cortisol; e por resposta de autoavaliação de ansiedade; as sessões duraram 60 minutos. Não foram encontradas correlações entre medidas fisiológicas e tomada de decisão egoísta, entretanto, encontrouse diferenças estatísticas significativas comportamentais entre os grupos: mulheres do grupo de controle são mais altruístas, quando dividem montantes mais altos de dinheiro; o grupo experimental avaliou como mais injustas ofertas egoístas (menor parte para ele(a)) do montante mais baixo e também como menos injustas ofertas altruístas (maior parte para ele(a)) do montante mais alto; os grupos também diferiram significativamente na oferta de divisão feita a desconhecidos; ademais, o grupo experimental levou mais tempo para iniciar a tarefa de planejamento do que o controle para ambos sexos. Concluise que medidas fisiológicas não se relacionam aos resultados pósestresse, porém diferenças comportamentais podem ser analisadas. Inferese que mulheres tem comportamentos mais altruístas por influência cultural. Percepção de justiça aumentada, comportamento egoísta e aumento do tempo de preparação na tarefa de planejamento podem ser o resultado do aumento da carga cognitiva por efeito da indução de estresse. / Altruism is an important behavioral construct in social relations; even though it appears to be no immediate gain in selfless actions. The purpose of promoting the group's and society’s progress results in the agent's own benefit. Goals are more easily achieved with the help of others, while there is improvement in the quality of social relations. Some factors have influence in altruistic behavior, stress is one of them; inducing acute stress can be effective in checking behaviors in imediate reaction in the laboratory, although there is no consensus on how this modifies intentions to help others and prosocial behavior. Stress can also influence how we evaluate the distribution of cash or goods made by others: perception of justice. The Dictator Game proves efficient to analize altruism and sense of justice, and salivary cortisol has shown able to assist in the analysis of acute stress. This study evaluated the impact of acute stress induction on 94 university students of different graduation courses of the Federal University of Rio Grande do Sul. Acute stress was induced via social stress task (Trier Social Stress Task) to identify if it relates to altruistic behavior and the negative assessment to unfair money distribution in two computerized dictator games. The subjects in both games were unknown to each other. Subjects were divided by sex and than two groups: experimental stress condition and control placebo condition. The fictitious money used to play was won in a planning task, followed by the stress induction. The impact was measured by two physiological metrics: heart rate and saliva collection for cortisol analysis; and the selfassessment test of anxiety. Each individual sessions lasted 60 minutes. Correlations between physiological measurements and the making of selfish decision were not found. However, significant statistical behaviors differences were found between: the control group of women who were more altruistic when dividing larger amounts of money; t he experimental group evaluated selfish money offers as more unfair in the lower cash amount experiment (lower share for him/her). We also found as less unfair the altruistic offers made on the experiment’s larger cash amount (highest share for him/her). The groups also differ significantly in the division of money made to unknown individuals; in addition, the experimental group took longer to start the planning task than the control group for both sexes. We conclude that physiological measures are not related to poststress results, but behavioral differences can be analyzed. It appears that women tend to be more altruistic because of cultural influence. Increased perception of justice, selfish behavior and longer time taking to plan the planning task can be the result of increased cognitive overload as a result of induction of stress.

Submitted by ADRIANA BEATRIZ BARRETTO (adriana.barretto@gmail.com) on 2018-04-25T17:07:16Z No. of bitstreams: 1 Tese Definitiva.pdf: 1000337 bytes, checksum: aa40cdf128c269fcfa1393bb66b32c79 (MD5) / Approved for entry into archive by Sulamita Selma C Colnago null (sulamita@btu.unesp.br) on 2018-04-26T18:52:18Z (GMT) No. of bitstreams: 1 barreto_ab_dr_bot_int.pdf: 1000337 bytes, checksum: aa40cdf128c269fcfa1393bb66b32c79 (MD5) / Made available in DSpace on 2018-04-26T18:52:18Z (GMT). No. of bitstreams: 1 barreto_ab_dr_bot_int.pdf: 1000337 bytes, checksum: aa40cdf128c269fcfa1393bb66b32c79 (MD5) Previous issue date: 2018-03-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / CAPÍTULO 1 – Neste estudo avaliamos o efeito do estresse agudo e crônico na memória de aprendizagem de tilápias-do-Nilo com diferentes perfis de personalidade. Inicialmente definimos a personalidade dos peixes através de testes de objeto novo e exposição a um predador, classificando-os em shy (tímido) ou bold (ousado) e em seguida estes indivíduos foram condicionados por um método simples de condicionamento clássico como forma de aprendizagem para posterior avaliação da memória. Os peixes shy foram então divididos em dois grupos, sendo que em um deles os peixes foram diariamente estressados por hipóxia, perseguição com rede ou confinamento (grupo shy-experimental) por 64 dias consecutivos, enquanto que no outro grupo os peixes permaneceram apenas isolados (grupo shy-controle) pelo mesmo período de tempo. O mesmo procedimento foi adotado com os peixes classificados como bold. Nesse mesmo período, testes de memória foram realizados em dias específicos, tanto nos grupos experimental quanto nos grupos controle. Ao final do experimento, reavaliamos se as personalidades se mantiveram. Obtivemos que o estresse agudo afetou a memória de aprendizado em peixes, principalmente em indivíduos com perfil de personalidade shy. CAPÍTULO 2 – Aqui desenvolvemos uma metodologia simples de condicionamento clássico facilmente aplicável em laboratórios de experimentação com peixes, quando comparados aos métodos descritos na literatura atual, onde os estímulos geralmente aplicados para condicionamento (som ou luz) podem interferir nas respostas dos animais experimentais presentes no mesmo laboratório. Para tal condicionamento, isolamos os peixes em aquários individuais e introduzimos um jato de água em cada aquário (sem que os peixes pudessem perceber a presença do pesquisador) causando movimentação da água (estímulo condicionado) neste local específico do aquário. Em seguida, um pellet de ração (estímulo incondicionado) foi introduzido no mesmo local da movimentação da água (novamente sem que os peixes pudessem perceber a presença do pesquisador). Esses procedimentos foram realizados durante 20 dias seguidos, 4 vezes ao dia. Obtivemos que após 14 dias de condicionamento todos os peixes associaram estímulo condicionado e incondicionado, confirmando a efetividade deste método simples e sem interferência nos demais animais experimentais presentes no ambiente. / CHAPTER 1 - In this study we evaluated the effect of acute and chronic stress in learning memory of Nile tilapia with different personality profiles. Initially we defined the personality of the fish through the testo f new object and exposure to a predator, classifying them as shy or bold, and then these individuals were conditioned by a simple method of classical conditioning as a way of learning to evaluation of memory. The shy fish were divided into two groups, and in one group the fish were daily stressed by hypoxia, net chase or confinement (shy-experimental group) for 64 consecutive days, while in the other group the fish remained only isolated (shy-control group) for the same time period. The same procedure was adopted with fish classified as bold. During the same period, memory tests were performed on specific days, in both groups, experimental and control group. At the end of the experiment, we reevaluated whether the personalities held. We found that acute stress affected learning memory in fish, especially in individuals with shy personality profiles. CHAPTER 2 - Here we develop a classical conditioning methodology easily applicable in fish experimentation laboratories when compared to the methods described in the current literature, where the stimuli generally applied for conditioning (sound or light) can interfere with the responses of experimental animals present in the same laboratory. For this conditioning, we isolate the fish in individual aquariums and introduce a jet of water into each aquarium (without the fish could perceive the presence of the researcher) causing water movement (conditioned stimulus) in this specific aquarium site. Then a feed pellet (unconditioned stimulus) was introduced in the same place as the water movement (again without the fish being able to perceive the presence of the researcher). These procedures were performed for 20 consecutive days, 4 times daily. We obtained that after 14 days of conditioning all the fish associated conditioned and unconditioned stimulus, confirming the effectiveness of this simple method and without interference in the other experimental animals present in the environment.

O altruísmo é um importante constructo comportamental envolvido nas relações sociais; mesmo que aparentemente não haja ganho imediato em ações altruístas, o objetivo de favorecer o progresso do grupo e da sociedade resulta no beneficiamento do próprio agente. Objetivos são mais facilmente alcançados com a ajuda de outros, ao mesmo tempo que há melhora na qualidade das relações sociais. Alguns fatores influenciam o comportamento altruísta, o estresse é um deles; a indução aguda de estresse pode ser eficiente em verificar comportamentos a curto prazo em laboratório, apesar de não haver consenso de que maneira este modifica as intenções de ajuda e o comportamento prósocial. O estresse também pode influenciar a maneira como avaliamos a distribuição de dinheiro ou bens feita por outrem: percepção de justiça. O Jogo do Ditador mostrase eficiente para analisar altruísmo e percepção de justiça, assim como o cortisol salivar se mostra capaz em auxiliar a análise do estresse agudo. Este trabalho avaliou em 94 estudantes universitários, de diversos cursos da Universidade Federal do Rio Grande do Sul, se a indução de estresse agudo via tarefa de estresse social (T rier Social Stress Task ) relacionase a comportamentos altruístas e maior avaliação negativa para divisões injustas de dinheiro em dois jogos do ditador computadorizados a interação em ambos foi com desconhecidos. Os grupos foram divididos em dois sexos e em duas condições: experimental estresse e controle placebo. O dinheiro fictício usado para jogar foi ganho em uma tarefa de planejamento, executada em seguida da indução de estresse. Este foi mensurado por duas medidas fisiológicas: batimentos cardíacos e coleta de saliva para análise de cortisol; e por resposta de autoavaliação de ansiedade; as sessões duraram 60 minutos. Não foram encontradas correlações entre medidas fisiológicas e tomada de decisão egoísta, entretanto, encontrouse diferenças estatísticas significativas comportamentais entre os grupos: mulheres do grupo de controle são mais altruístas, quando dividem montantes mais altos de dinheiro; o grupo experimental avaliou como mais injustas ofertas egoístas (menor parte para ele(a)) do montante mais baixo e também como menos injustas ofertas altruístas (maior parte para ele(a)) do montante mais alto; os grupos também diferiram significativamente na oferta de divisão feita a desconhecidos; ademais, o grupo experimental levou mais tempo para iniciar a tarefa de planejamento do que o controle para ambos sexos. Concluise que medidas fisiológicas não se relacionam aos resultados pósestresse, porém diferenças comportamentais podem ser analisadas. Inferese que mulheres tem comportamentos mais altruístas por influência cultural. Percepção de justiça aumentada, comportamento egoísta e aumento do tempo de preparação na tarefa de planejamento podem ser o resultado do aumento da carga cognitiva por efeito da indução de estresse. / Altruism is an important behavioral construct in social relations; even though it appears to be no immediate gain in selfless actions. The purpose of promoting the group's and society’s progress results in the agent's own benefit. Goals are more easily achieved with the help of others, while there is improvement in the quality of social relations. Some factors have influence in altruistic behavior, stress is one of them; inducing acute stress can be effective in checking behaviors in imediate reaction in the laboratory, although there is no consensus on how this modifies intentions to help others and prosocial behavior. Stress can also influence how we evaluate the distribution of cash or goods made by others: perception of justice. The Dictator Game proves efficient to analize altruism and sense of justice, and salivary cortisol has shown able to assist in the analysis of acute stress. This study evaluated the impact of acute stress induction on 94 university students of different graduation courses of the Federal University of Rio Grande do Sul. Acute stress was induced via social stress task (Trier Social Stress Task) to identify if it relates to altruistic behavior and the negative assessment to unfair money distribution in two computerized dictator games. The subjects in both games were unknown to each other. Subjects were divided by sex and than two groups: experimental stress condition and control placebo condition. The fictitious money used to play was won in a planning task, followed by the stress induction. The impact was measured by two physiological metrics: heart rate and saliva collection for cortisol analysis; and the selfassessment test of anxiety. Each individual sessions lasted 60 minutes. Correlations between physiological measurements and the making of selfish decision were not found. However, significant statistical behaviors differences were found between: the control group of women who were more altruistic when dividing larger amounts of money; t he experimental group evaluated selfish money offers as more unfair in the lower cash amount experiment (lower share for him/her). We also found as less unfair the altruistic offers made on the experiment’s larger cash amount (highest share for him/her). The groups also differ significantly in the division of money made to unknown individuals; in addition, the experimental group took longer to start the planning task than the control group for both sexes. We conclude that physiological measures are not related to poststress results, but behavioral differences can be analyzed. It appears that women tend to be more altruistic because of cultural influence. Increased perception of justice, selfish behavior and longer time taking to plan the planning task can be the result of increased cognitive overload as a result of induction of stress.