Quantifying aggressive behavior in zebrafish

Aggression is a complex behavior that influences social relationships and can be seen as adaptive or maladaptive depending on the context and intensity of expression. A model organism suitable for genetic dissection of the underlying neural mechanisms of aggressive behavior is still needed. Zebrafish has already proven to be a powerful vertebrate model organism for the study of normal and pathological brain function. Despite the fact that zebrafish is a gregarious species that forms shoals, when allowed to interact in pairs, both males and females express aggressive behavior and establish dominance hierarchies. Here, we describe two protocols that can be used to quantify aggressive behavior in zebrafish, using two different paradigms: (1) staged fights between real opponents and (2) mirror-elicited fights. We also discuss the methodology for the behavior analysis, the expected results for both paradigms, and the advantages and disadvantages of each paradigm in face of the specific goals of the study.

Belief in a just world and secondary victimization : The role of adolescent deviant behavior

Belief in a Just World research found evidence that one feels threatened whenever one witnesses an innocent victim suffering, often resorting to secondary victimization to neutralize the observed injustice. However, literature has neglected the explanatory power of adolescent deviant behavior in victimization processes. This study (n = 284 students) aims to determine the impact of the adolescents' deviant behavior, BJW and victim's innocence on secondary victimization. Additionally, we analyzed juvenile deviant behavior's impact on victim identification. Juveniles who committed more deviant behaviors identified less with the victim than those with lower deviance levels. The interaction effects show that juveniles who are strong just world believers and have higher delinquency engaged significantly more in secondary victimization when confronted with an innocent victim. These results clarify the role played by adolescent deviant behavior and BJW in secondary victimization judgments regarding situations with innocent and non-innocent victims.

Experiências de (in)justiça com os professores e comportamentos de desvio na adolescência

Tese de Doutoramento em Psicologia na área de especialidade Psicologia Social

Semantics bias in cross-national comparative analyses : Is it good or bad to have "fair" health?

The Health Behavior in School-aged Children is a cross-national study collecting data on social and health indicators on adolescents in 43 countries. The study provides comparable data on health behaviors and health outcomes through the use of a common protocol, which have been a back bone of the study sine its initiation in 1983. Recent years, researchers within the study have noticed a questionable comparability on the widely used item on self-rated health. One of the four response categories to the item "Would you say your health is….?" showed particular variation, as the response category "Fair" varied from 20 % in Latvia and Moldova to 3-4 % in Bulgaria and Macedonia. A qualitative mini-survey of the back-translations showed that the response category "Fair" had a negative slant in 25 countries, a positive slant in 10 countries and was considered neutral in 9 countries. This finding indicates that there are what may be called semantic issues affecting comparability in international studies, since the same original word (in an English original) is interpreted differently across countries and cultures. The paper test and discuss a few possible explanations to this, however, only leaving to future studies to hold a cautious approach to international comparisons if working with the self-rated health item with four response categories.