Neuro-Behavioral Dynamic Prediction of Interpersonal Cooperation and Aggression / 神经科学通报·英文版

How to quickly predict an individual's behavioral choices is an important issue in the field of human behavior research. Using noninvasive electroencephalography, we aimed to identify neural markers in the prior outcome-evaluation stage and the current option-assessment stage of the chicken game that predict an individual's behavioral choices in the subsequent decision-output stage. Hierarchical linear modeling-based brain-behavior association analyses revealed that midfrontal theta oscillation in the prior outcome-evaluation stage positively predicted subsequent aggressive choices; also, beta oscillation in the current option-assessment stage positively predicted subsequent cooperative choices. These findings provide electrophysiological evidence for the three-stage theory of decision-making and strengthen the feasibility of predicting an individual's behavioral choices using neural oscillations.

Suicidal patients in a psychiatric emergency unit: clinical characteristics and aggression profile / Pacientes suicidas em uma unidade de emergência psiquiátrica: características clínicas e perfil de agressão

Abstract Objective To explore and describe a profile of patients admitted to a psychiatric emergency facility, comparing patients with and without a recent suicide attempt in terms of their clinical characteristics and aggression. Methods This was an exploratory comparative study where patients were assessed using the Brief Psychiatric Rating Scale (BPRS) and the Overt Aggression Scale (OAS). Participants with a suicide attempt in the last 24 hours (SA) were compared to participants with a prior history of suicide attempt but no recent attempt (PHSA). Results 63 individuals (SA: 26; PHSA: 37) were selected. Both groups had similar demographic and clinical characteristics. The most prevalent diagnoses were mood (57.1%) and personality (50.8%) disorders. The majority of patients in both groups had a history of aggression episodes. Physical aggression in the week prior to admission was more prevalent in the PHSA group (51.4 vs. 19.2%, p = 0.017). The PHSA group also presented higher activation scores (p = 0.025), while the SA group presented higher affect scores on BPRS dimensions (p = 0.002). Conclusion The majority of individuals with a history of suicide attempt also presented a history of aggression. Inpatients with recent suicide attempt were hospitalized mainly due to the risk of suicide, while those with no recent suicide attempt were hospitalized mainly due to the risk of hetero-aggression. These findings support the hypothesis of an aggressive profile in suicidal patients and may open up a path for future research.

Resumo Objetivo Explorar e descrever o perfil de pacientes internados em uma unidade de emergência psiquiátrica, comparando os pacientes com e sem tentativa recente de suicídio em termos de suas características clínicas e agressividade. Métodos Trata-se de um estudo exploratório comparativo, onde os pacientes foram avaliados por meio da Escala Breve de Avaliação Psiquiátrica (BPRS) e da Escala de Agressividade Declarada (OAS). Os participantes com tentativa de suicídio (TS) nas últimas 24 horas foram comparados com participantes com história prévia de tentativa de suicídio, mas sem tentativa recente (HPTS). Resultados Foram selecionados 63 indivíduos (TS: 26; HPTS: 37). Ambos os grupos tinham características demográficas e clínicas semelhantes. Os diagnósticos mais prevalentes foram transtornos de humor (57,1%) e de personalidade (50,8%). A maioria dos pacientes em ambos os grupos apresentava história de agressão. A agressão física na semana anterior à internação foi mais prevalente no grupo HPTS (51,4 vs. 19,2%, p = 0,017). O grupo HPTS também apresentou maior ativação (p = 0,025), enquanto o grupo TS apresentou maior afetividade nas dimensões da BPRS (p = 0,002). Conclusão A maioria dos indivíduos com história de tentativa de suicídio também apresentou história de agressão. Os pacientes internados com tentativa recente de suicídio foram hospitalizados principalmente devido ao risco de suicídio, enquanto aqueles sem tentativa recente de suicídio foram hospitalizados principalmente devido ao risco de heteroagressão. Esses achados apoiam a hipótese de um perfil agressivo em pacientes suicidas e podem abrir caminho para pesquisas futuras.

Cognitive-behavioral group therapy for intermittent explosive disorder: description and preliminary analysis

Objectives: To evaluate the efficacy of a group therapy based on cognitive-behavioral techniques customized for intermittent explosive disorder (IED). The current report presents the preliminary results of a clinical trial comparing pre- and post-intervention scores in different anger dimensions. Methods: The studied sample consisted of 84 treatment-seeking subjects. The mean (standard deviation) age was 43.0 (11.9) years, and 78% were male. The therapeutic group program consisted of 15 weekly sessions plus three maintenance sessions. The sessions lasted approximately 90 minutes each. Results: No differences were found in demographic profile and pre-treatment status between subjects who completed treatment (n=59) and dropouts (n=25). Comparison of State-Trait Anger Expression Scale (STAXI) scores pre- and post-treatment showed statistically significant changes in all anger scales and subscales of the questionnaire. Conclusion: This preliminary report is a significant addition to currently scarce clinical data. Our findings provide further evidence that structured cognitive-behavioral group therapy, with a focus on anger management and cognitive coping, may be a promising approach to the treatment of IED.

Social instigation and repeated aggressive confrontations in male Swiss mice: analysis of plasma corticosterone, CRF and BDNF levels in limbic brain areas / Instigação social e confrontos agressivos repetidos em camundongos Swiss machos: análise de corticosterona plasmática e dos níveis de CRF e BDNF em áreas cerebrais límbicas

Abstract Introduction: Agonistic behaviors help to ensure survival, provide advantage in competition, and communicate social status. The resident-intruder paradigm, an animal model based on male intraspecific confrontations, can be an ethologically relevant tool to investigate the neurobiology of aggressive behavior. Objectives: To examine behavioral and neurobiological mechanisms of aggressive behavior in male Swiss mice exposed to repeated confrontations in the resident intruder paradigm. Methods: Behavioral analysis was performed in association with measurements of plasma corticosterone of mice repeatedly exposed to a potential rival nearby, but inaccessible (social instigation), or to 10 sessions of social instigation followed by direct aggressive encounters. Moreover, corticotropin-releasing factor (CRF) and brain-derived neurotrophic factor (BNDF) were measured in the brain of these animals. Control mice were exposed to neither social instigation nor aggressive confrontations. Results: Mice exposed to aggressive confrontations exhibited a similar pattern of species-typical aggressive and non-aggressive behaviors on the first and the last session. Moreover, in contrast to social instigation only, repeated aggressive confrontations promoted an increase in plasma corticosterone. After 10 aggressive confrontation sessions, mice presented a non-significant trend toward reducing hippocampal levels of CRF, which inversely correlated with plasma corticosterone levels. Conversely, repeated sessions of social instigation or aggressive confrontation did not alter BDNF concentrations at the prefrontal cortex and hippocampus. Conclusion: Exposure to repeated episodes of aggressive encounters did not promote habituation over time. Additionally, CRF seems to be involved in physiological responses to social stressors.

Resumo Introdução: Comportamentos agonísticos ajudam a garantir a sobrevivência, oferecem vantagem na competição e comunicam status social. O paradigma residente-intruso, modelo animal baseado em confrontos intraespecíficos entre machos, pode ser uma ferramenta etológica relevante para investigar a neurobiologia do comportamento agressivo. Objetivos: Analisar os mecanismos comportamentais e neurobiológicos do comportamento agressivo em camundongos Swiss machos expostos a confrontos repetidos no paradigma residente-intruso. Métodos: A análise comportamental foi realizada em associação com medidas de corticosterona plasmática em camundongos expostos repetidamente a um rival em potencial próximo, porém inacessível (instigação social), ou a 10 sessões de instigação social seguidas de encontros agressivos diretos. Além disso, o fator de liberação de corticotrofina (CRF) e o fator neurotrófico derivado do cérebro (BNDF) foram medidos no encéfalo desses animais. Camundongos controles não foram expostos à instigação social ou confrontos agressivos. Resultados: Os camundongos expostos a confrontos agressivos exibiram um padrão semelhante de comportamentos agressivos e não agressivos típicos da espécie na primeira e na última sessão. Em contraste com instigação social apenas, confrontos agressivos repetidos promoveram aumento na corticosterona plasmática. Após 10 sessões de confrontos agressivos, os camundongos apresentaram uma tendência não significativa de redução dos níveis de CRF no hipocampo, que se correlacionaram inversamente com os níveis plasmáticos de corticosterona. Por outro lado, sessões repetidas de instigação social ou confronto agressivo não alteraram as concentrações de BDNF no córtex pré-frontal e hipocampo. Conclusão: A exposição a episódios repetidos de encontros agressivos não promoveu habituação ao longo do tempo. Adicionalmente, o CRF parece estar envolvido nas respostas fisiológicas aos estressores sociais.

Concepciones de infancia en una escuela con altos índices de violencia escolar de estudiantes a profesores / Conceptions of infancy in school with high rates of school violence student to teachers / Concepções de infância na escola com altas taxas de professores-estudantes violência escolar

A través de un estudio cuasietnográfico en una escuela primaria con altos índices de intimidación de los estudiantes hacia sus profesores, se busca analizar las concepciones de infancia implícitas en los discursos de la comunidad escolar y su sentido para la validación de prácticas e interacciones escolares violentas. Para ello, se realizaron observaciones persistentes, entrevistas individuales y grupales y análisis de documentos oficiales, los que fueron analizados bajo el análisis de contenido categorial temático. Los resultados muestran cómo la Escuela activa diversos mecanismos para validar la infancia como espacio de tránsito, y coloca como referente una forma de adultocentrismo que se expresa en prácticas de control y discriminación. Se discuten los sentidos construidos acerca de la niñez y sus implicancias para la construcción de subjetividades infantiles.

This is a study in a primary school with high indexes of intimidation from the students to his professors. It looks for analyse the conceptions of implicit infancy in the discourses of the school community. For this study, we made persistent observations, to individual participants and groups interviews, analysis of official documents that were conducted and analysed under the analysis of thematic categorial content. The results show how the schools are using some mechanisms to validate the infancy like space of passage. The schools are placing like referent for this mechanism a form of adultcentrism that it express in practices of control and discrimination. The senses built about childhood and its implications for the construction of children’s subjectivities are discussed.

Por meio de uma pesquisa cuasietnográfica em uma escola primária com altos índices de intimidação de alunos para com seus professores, busca-se analisar as concepções de infância implícitas nos discursos da comunidade escolar. Para isso se realizaram observações persistentes, entrevistas individuais e grupais e foram examinados documentos oficiais, informação que foi analisada por meio da análise de conteúdo categorial temático. Os resultados mostram como a Escola ativa diversos mecanismos para validar a infância como espaço de trânsito, colocando como referente para isso uma forma de adultocentrismo que por sua vez se expressa em práticas de controle e discriminação. Os sentidos construídos sobre a infância e suas implicações para a construção de subjetividades das crianças são discutidos.

Effects of REM sleep restriction during pregnancy on rodent maternal behavior

Objective: To evaluate the effects of sleep restriction during pregnancy on maternal care and maternal aggression in a rodent model. Methods: Twenty-three female Wistar rats were assigned to one of two groups: control (n=12) or sleep restriction (n=11) during the entire pregnancy. At the fifth postpartum day, the animals were subjected to the resident-intruder paradigm and to the pup retrieval test. Results: Sleep restriction during pregnancy had no direct effects on maternal care. Regarding aggressive behavior, defensive aggression was increased by sleep loss, with a lower responsiveness threshold to hostile environmental stimuli. Sleep deprivation during gestation also reduced self-grooming behavior. Conclusion: Taking increased self-grooming as a behavioral correlate of anxiety in rodents, this study provides evidence that lactating dams were in a condition of reduced anxiety. From an adaptive perspective, this pattern of stress response may function to ensure proper maternal behavior, thereby guaranteeing the survival and viability of the litter. Under a translational perspective, the present article confronts the importance of biological and adaptive features to rodent maternal behavior with the relevance of sociocultural factors to the human mother-infant relationship and to the onset of postpartum depression.

Ethanol during adolescence decreased the BDNF levels in the hippocampus in adult male Wistar rats, but did not alter aggressive and anxiety-like behaviors / O etanol durante a adolescência reduziu os níveis de BDNF no hipocampo de ratos Wistar machos adultos, mas não alterou os comportamentos agressivos e a ansiedade

Objective:To investigate the effects of ethanol exposure in adolescent rats during adulthood by assesssing aggression and anxiety-like behaviors and measuring the levels of inflammatory markers.Methods:Groups of male Wistar rats (mean weight 81.4 g, n = 36) were housed in groups of four until postnatal day (PND) 60. From PNDs 30 to 46, rats received one of three treatments: 3 g/kg of ethanol (15% w/v, orally, n = 16), 1.5 g/kg of ethanol (12.5% w/v, PO, n = 12), or water (n = 12) every 48 hours. Animals were assessed for aggressive behavior (resident x intruder test) and anxiety-like behaviors (elevated plus maze) during adulthood.Results:Animals that received low doses of alcohol showed reduced levels of brain-derived neurotrophic factor (BDNF) in the hippocampus as compared to the control group. No significant difference was found in prefrontal cortex.Conclusions:Intermittent exposure to alcohol during adolescence is associated with lower levels of BDNF in the hippocampus, probably due the episodic administration of alcohol, but alcohol use did not alter the level agression toward a male intruder or anxiety-like behaviors during the adult phase.

Objetivo: Investigar os efeitos da exposição ao etanol em ratos adolescentes durante a idade adulta sobre os comportamentos agressivos e semelhantes à ansiedade, bem como sobre as medidas de níveis de marcadores inflamatórios.Métodos:Os grupos de ratos Wistar machos (peso médio de 81,4 g; n = 36) foram alojados em grupos de quatro até o dia pós-natal (DPN) 60. Entre os DPNs 30 e 46, os ratos receberam um dos três tratamentos: 3 g/kg de etanol (15% w/v, oralmente, n = 16), 1.5 g/kg de etanol (12,5% w/v, oralmente, n = 12), ou água (n = 12) a cada 48 horas. Os comportamentos agressivos (teste residente-intruso) e semelhantes à ansiedade (labirinto em cruz elevado) foram avaliados durante a idade adulta dos animais.Resultados:Os animais que receberam doses menores de álcool mostraram níveis reduzidos de fator neurotrófico derivado do cérebro (BDNF) no hipocampo quando comparados ao grupo controle. Nenhuma diferença significativa foi verificada no córtex pré-frontal.Conclusões:A exposição intermitente ao álcool durante a adolescência é associada com menores níveis de BDNF no hipocampo, provavelmente divido a administração episódica de álcool, mas o uso não alterou o nível de agressão contra o macho intruso ou os comportamentos semelhantes à ansiedade durante a fase adulta.

Correlation between the eicosapentaenoic acid, docosahexaenoic acid and the aggressive behavior in mice / 法医学杂志

OBJECTIVE@#To explore the correlation between the eicosapentaenoic acid(EPA), docosahexaenoic acid (DHA) and the aggressive behavior in mice.@*METHODS@#Seventy-two male Kunming mice were divided into control group, fish oil group, simvastatin group and aggressive reference group randomly. The control group, fish oil group and simvastatin group were given normal saline, fish oil and simvastatin by irrigation respectively for 3 months consecutively, each mouse was raised isolatedly. The latent period of assault, the frequencies of tail swing and assault, and the cumulative time of assault were recorded at the beginning and the end of the intervention. Finally, the EPA and DHA in brain were analyzed by gas chromatography-mass spectrometry (GC-MS). The aggressive reference group was raised without intervention and was evaluated as aggressive reference only.@*RESULTS@#(1) Before intervention, the latent period of assault, the frequencies of tail swing, the frequencies of assault, and the cumulative time of assault were not significantly different from each other group. After intervention, the differences were significant (P<0.05). (2) After the intervention, the content of EPA and DHA in mice brain was the most in the fish oil group, and the least in the simvastatin group. (3) The content of EPA was negatively related with the four indexes (P<0.05) before and after the intervention. The content of DHA was negatively related with the frequencies of tail swing and assault (P<0.05).@*CONCLUSION@#There is a correlation between the EPA, DHA and aggressive behavior in mice under stress.

Physical abuse of older people reported at the Institute of Forensic Medicine in Recife, Pernambuco State, Brazil / A violência física contra a pessoa idosa revelada em serviço médico-legal, Recife, Pernambuco, Brasil

Conduziu-se um estudo transversal com o objetivo de determinar o perfil da violência física em idosos submetidos à perícia traumatológica, entre 2004 e 2007, no Instituto de Medicina Legal do Recife, Pernambuco, Brasil. Os casos, cujas informações procederam de 1.027 laudos, foram descritos segundo características do evento, da vítima e do agressor. Com maior freqüência, a violência foi produzida por energia mecânica, instrumento contundente e arma natural; ocorreu num domingo, turno noturno e residência da vítima; acometeu mais de uma parte do corpo e a lesão foi leve. Prevaleceram como vítimas os homens, com idade entre 60 e 69 anos, pardos, casados/união consensual e aposentados/pensionistas. A maioria dos agressores era homem, conhecido da vítima e a agrediu desacompanhado. A transcendência social do problema torna imperativo o investimento em programas para seu enfrentamento, possibilitando uma melhor qualidade de vida para o idoso.

This cross-sectional study aimed to determine the profile of physical abuse against older people who underwent forensic examination at the Institute of Forensic Medicine in Recife, Pernambuco State, Brazil. The cases, with data from 1,027 forensic reports, were described according to characteristics of the incident, victim, and aggressor. Most cases of violence were produced by mechanical energy, either with blunt objects or by empty-handed attack; the most common day of the week was Sunday, most frequently in the evening, and in the victim's home; typical cases involved mild injuries on more than one part of the victim's body. The majority of the victims were men, 60 to 69 years of age, brown (mixed-race), married or living with a partner, and retirees/pensioners. The majority of the aggressors were men, known to the victim, and attacking alone. The social transcendence of violence against older people clearly calls for investment in programs to deal with the problem in order to ensure better quality of life for the elderly.

Evaluation of antiaggressive activity of Eclipta alba in experimental animals

The occurrence of aggression for prolonged periods of time could have a hazardous impact on the health and social wellbeing of the individual. Aggression can ensue due to exposure to an intimidating situation. Aggression is prominently seen when a disturbance occurs in the fine balance of neurotransmitters such as 5-hydroxytryptamine, gamma- aminobutyric acid, dopamine and their receptor subtypes. The present study investigated the ability of 100 and 200mg/kg of aqueous extract of Eclipta alba to circumvent aggression. Foot shock induced aggression and water competition test were utilized as models for screening of antiaggressive activity. Eclipta alba significantly minimized dominance [p < 0.05] which is correlated to the level of aggression particularly with 200mg/kg in the water competition test. A tangible behavioral submission was observed with 100 and 200mg/kg and of Eclipta alba in the foot shock induced test

Study of the social hierarchy and territoriality of Calomys callosus Rengger, 1830 (Rodentia: Cricetidae)

The genus Calomys comprises a lot of species distributed throughout South America. The species C. callosus Rengger, 1830 occur in Brazil, been often used in laboratory experiments. This work involved a study of aggressive behavior and dominance, which are aspects related to hierarchy and territoriality, among C. callosus males kept in a laboratory. The establishment of a hierarchy was observed, with the dominant animals controlling the space, food and water, while the remaining animals were confined to a restricted space. The intensity of aggression and variations in the number of attacks declined over time as a result of the formation of the hierarchy. No wounds were observed, probably due to the ritualistic nature of the attacks.

O genêro Calomys inclui várias espécies encontradas na América do Sul. A espécie C. callosus Rengger, 1830 ocorre no Brasil, sendo freqüentemente utilizada em experimentos de laboratório. Neste trabalho foram estudados, em machos mantidos em laboratório, o comportamento agressivo e a dominância, aspectos relacionados à hierarquia e territorialidade. Foi observado o estabelecimento de hierarquia, com os animais dominantes controlando o espaço, o alimento e a água, ficando os demais confinados em um espaço restrito. A intensidade das agressões e as variações no número de ataques diminuiram com o tempo, uma conseqüência da formação de hierarquia. Não foram observados ferimentos, devido provavelmente à ritualização dos ataques.

Mating system of the amazonian cichlid angel fish, Pterophyllum scalare

The species, Pterophyllum scalare distinguishes itself by its breeding behavior, involving competition for territory, sexual partners, courtship and parental care. The purpose of this study was to identify the mating system adopted by this species of fish. Twenty males and twenty females were observed under semi-natural and experimental conditions to test the hypothesis of serial monogamy. Under semi-natural conditions, after the third breeding cycle, the couples changed mates. Under experimental conditions, the couples changed partners after the first breeding cycle. Under experimental conditions, mate recognition was investigated through the preference of the females, indicated by the time they spent with the males. The females were available or not for courtship from new males, depending on their aggressiveness or submission. The larger and more aggressive males obtained new mating opportunities while the submissive males were rejected by the females. The mated fish were aggressive towards intruders in the presence of the mate, protecting their pair bond. In the interval between breeding cycles, the couples did not display aggression towards intruders, confirming the hypothesis of serial monogamy. Best mate selection by the females and the opportunity of new matings for both sexes influenced the reproductive success of this species.

A espécie Pterophyllum scalare se destaca pela complexidade de seu comportamento reprodutivo, envolvendo competição por território e parceiros sexuais, corte, acasalamento e cuidado parental. Este trabalho teve como objetivo identificar o tipo de sistema de acasalamento adotado pelos peixes desta espécie. Vinte machos e vinte fêmeas foram observados nas situações seminatural e experimental para testar a hipótese de monogamia serial. Em situação seminatural, após o terceiro ciclo reprodutivo, os casais mudaram de parceiros, enquanto que, em situação experimental, os casais mudaram de parceiros a partir do primeiro ciclo reprodutivo. Em situação experimental foi investigado o reconhecimento do parceiro, pela permanência das fêmeas que se mostraram disponíveis ou não à corte de novos machos, em função da agressividade e submissão deles. Machos maiores e mais agressivos obtiveram novas oportunidades de acasalamento e machos submissos foram rejeitados pelas fêmeas. Os peixes acasalados foram agressivos a intrusos na presença do parceiro, protegendo a ligação do par. No intervalo entre os ciclos reprodutivos, os pares não mostraram agressão a intrusos, confirmando a hipótese de monogamia serial. A escolha do melhor parceiro pelas fêmeas e a oportunidade de novos acasalamentos para ambos os sexos influenciaram o sucesso reprodutivo desta espécie.

Behavioural and chemical studies of discrimination processes in the leaf-cutting ant Acromyrmex laticeps nigrosetosus (Forel, 1908) / Estudos químico e comportamental dos processos discriminatórios na formiga cortadeira Acromyrmex laticeps nigrosetosus (Forel, 1908)

Leaf-cutting ants live in symbiosis with a basidiomycete fungus that is exploited as a source of nutrients for ant larvae. Tests of brood transport revealed that Acromyrmex laticeps nigrosetosus workers did not discriminate a concolonial brood from an alien brood. The same result was observed with tests of fungus transport. Adult workers showed no aggressive behaviour to workers from other alien colonies (non-nestmates). There was no qualitative variation in the chemical profiles of larvae, pupae and adult workers from the different colonies. However, quantitative differences were observed between the different colonies. Hypotheses about the lack of intraspecific aggression in this subspecies of ants are discussed.

As formigas cortadeiras vivem em simbiose com um fungo basidiomiceto que é utilizado como fonte de nutriente para suas larvas. Testes de transporte de prole revelaram que as operárias de Acromyrmex laticeps nigrosetosus não discriminaram a prole concolonial de prole estranha. O mesmo resultado foi verificado com testes de transporte do fungo. As operárias adultas não exibiram comportamento agressivo frente a operárias de outras colônias (não companheiras de ninho). Não houve variação qualitativa nos perfis químicos de larvas, pupas e operárias adultas de diferentes colônias. No entanto, diferenças quantitativas foram observadas entre as diferentes colônias. Hipóteses sobre a ausência de agressão intra-específica nesta subespécie de formiga são discutidas.

Social isolation and aggressiveness in the Amazonian juvenile fish Astronotus ocellatus

Testamos o efeito do isolamento social sobre a agressividade no peixe amazônico, Astronotus ocellatus. Dez peixes juvenis foram transferidos de um aquário de agrupamento (60 x 60 x 40 cm) contendo 15 indivíduos (sem discriminação de sexo) para um aquário de isolamento (50 x 40 x 40 cm). A agressividade foi testada por meio de ataques e exibições direcionadas à imagem do peixe no espelho. O comportamento foi filmado durante 10 min em 4 momentos: 30 min, 1 dia, 5 dias e 15 dias após o isolamento. Nós analisamos a motivação agressiva por meio da latência para início do comportamento agonístico e pela freqüência dos ataques totais e específicos direcionados ao espelho. A latência para o comportamento agonístico reduziu ao longo do isolamento e houve uma tendência de aumento da freqüência de "mouth fighting" (um ataque de alta intensidade de agressão), mostrando-nos um aumento na motivação agressiva. Os resultados estão de acordo com os encontrados para ciclídeos juvenís de Haplochromis burtoni, mas discordam com os encontrados para Pterophylum scalare (acará bandeira). Sugerimos que o aumento da agressividade em A. ocellatus pode ser mediado pelo efeito de exposição prévia, da residência prévia ou por processos envolvendo reconhecimento de co-específicos.

Short-term aggressive behavior in scleractinian corals from La Blanquilla reef, Veracruz Reef System

The short-term aggressive behavior of scleractinian corals from La Blanquilla Reef, Veracruz Reef System, Gulf of Mexico was determined. Unilateral aggression, bilateral aggression and indifference were observed through experimental interspecific encounters in situ, in aquarium conditions and through direct observation of natural encounters on the reef. Species were characterized as highly aggressive, moderately aggressive and not very aggressive establishing a hierarchy with two competitive rings representing similar aggressive abilities among some species. Most observations of aggression were of extracoelenteric digestion. Mussa angulosa was the most aggressive species and Oculina diffusa the least. Apparently there is a direct relationship among aggressiveness and relative coverage as three of the most abundant corals at depths of 4-9 m Montastraea cavernosa, Colpophyllia natans and Montastraea annularis, are all highly aggressive, have massive growth and have a high relative coverage. Siderastrea siderea is the only dominant species that was not ranked as highly aggressive; its high coverage is due to other reasons.

Pup age and aggressive behavior in lactating rats

High levels of aggressive behaviors against intruders in the nest area are displayed by female rats during the first 10 days after delivery, declining thereafter to very low levels, even though lactation continues. Cross-fostering experiments were undertaken to test the hypothesis that pup age may affect aggression in lactating rats. The behavior of females on the 8th day after delivery when raising fostered 8-day-old pups was compared to that of females on the 8th postpartum day raising older pups (18 days old) for the last 5 days, and females on the 18th day after delivery raising fostered 18-day-old pups were compared to females in the same postpartum period nursing younger pups (8 days of age at the time of the maternal aggression test) for 5 days. Pup retrieval activity and plasma prolactin level were also analyzed. Females on the 8th postpartum day nursing 18-day-old pups were less aggressive than females in the same postpartum period, but with 8-day-old pups. Likewise, females on the 18th postpartum day nursing younger pups were more aggressive and presented higher levels of prolactin than females nursing older pups. Thus, pup development can alter the natural decline of maternal aggressive behavior

Isolation modifies the behavioural response in rats.

Twenty-four male wister rats were reared from weaning either alone (isolation reared) or in groups of five (socially reared) for 6 weeks. Thereafter, the present study examined and compared the behaviour of isolation and socially reared rats in the test of social interaction, in the elevated plus-maze test of anxiety, in the open field behavior of exploration and locomotion activity, and the depressive behaviour in forced swim test. Under high light in unfamiliar conditions isolation reared rats spent significantly more time in aggressive interactions (P < 0.05) and high levels of aggressive behaviour compared to the socially reared rats (P < 0.05). Isolation reared rats had spent less time in the open arms than the socially reared rats in the maze test (P < 0.05). Isolation reared rats were more exploratory than the socially reared rats in the open field test and the defaecation scores were less compared to the socially reared controls (P < 0.05). Isolated rats spent less time immobile on the rats' forced swim test behaviour but the difference was not statistically significant. These findings suggest that isolation reared rats are nervous, aggressive and hyperactive animals in a novel field. It appears that isolation rearing in the early stages of life has modified a variety of behaviour in the adult rats, and the investigation of the pattern of behavioural changes in isolation reared rats may help to explore the environmental influences on the development of human psychopathology.

Violencia intrafamiliar y doméstica para ellos: por una vida sin violencia / Domestic and domestic violence for them: for life without violence

La presente cartilla sobre violencia intrafamiliar y domestica dirigida a los varones, con el fin de lograr vivir una vida sin violencia, promoviendo la igualdad

Violencia intrafamiliar y doméstica para ellas: por una vida sin violencia / Domestic and domestic violence for them: for life without violence

Esta es una cartilla sobre la violencia en la familia contra la mujer, se orienta sobre lo que se debe hacer en casos de violencia