The behavioral tasks aiming to evaluate learning and memory mechanisms currently available to zebrafish (Danio rerio) involve long training sessions frequently along multiple days and are based on shuttle box or active-avoidance protocols, preventing a detailed analysis of cellular and molecular time-dependent processes involved in memory acquisition and consolidation. In order to explore zebrafish's potential contribution to the characterization of the molecular machinery underlying learning and memory rapidly acquired and reliable paradigms are necessary. In this study we present a rapid and effective learning protocol in a single-trial inhibitory avoidance in zebrafish. In a simple apparatus, adult animals learned to refrain from swimming from a white into a dark compartment in order to avoid an electric shock during a single-trial training session that lasted less than 2 min. The resulting memory is robust, long-lasting and sensitive to NMDA-receptor antagonist MK-801 given in the tank water immediately after training. Experiments aiming to further characterize the events underlying memory formation, retrieval or extinction or those looking for cognitive profiling of mutants, neurotoxicological studies and disease models may benefit from this task, and together with complementary strategies available for zebrafish may significantly improve our current knowledge on learning and memory mechanisms.

Zebrafish has been increasingly used in behavioral studies, but data can present high variability. Most studies have been performed using isolated zebrafish, despite their interactive nature and shoaling behavior. We compared adult zebrafish behavior and cortisol levels after exposure to novelty as well as sensitivity to Pentylenetetrazole (PTZ)-induced seizures in animals tested individually or in groups of three (triplets). In the exploratory behavior task, data from single fish and triplets were not significantly different, but single fish data were more disperse in latency, to enter and time spent in the tank upper part, and crossings. In the light-dark task, time in the light zone and crossings were not different between groups, but latency to enter the dark zone and data variability were. We also observed that the latency to reach stage III seizures induced by PTZ was higher in triplets, but data dispersion was not different from single fish. Finally, cortisol levels of fish individually exposed to a novel environment were higher and more variable than triplets, while both groups had higher levels than unmanipulated animals. Thus, when tested individually, zebrafish are more stressed and present more variable behavior due to disruption of their natural shoal strategies. These features can be beneficial or detrimental depending on study aims and should be considered when designing, analyzing, and interpreting zebrafish behavioral data.

No abstract

No abstract

O objetivo deste trabalho é apresentar as críticas feitas por neurocientistas às pesquisas que buscam diferenças cognitivas entre homens e mulheres presentes no cérebro, principalmente, utilizando o respaldo da neuroimagem. Desde o início dos anos 2000, a preocupação com a utilização da neurociência para justificar estereótipos de gênero e a falta de critério dos responsáveis para diferenciar as expressões “sexo” e “gênero” têm envolvido diversas neurocientistas no debate mais profundo entre natureza e cultura apresentado por essas pesquisas. Além disso, é imperativo pensarmos no impacto desses resultados, considerando que eles fornecem argumentos para os diversos discursos sociais e contribuem muito para o entendimento das habilidades humanas.

Este artigo tem como objetivo analisar diferentes discursos teóricos que se propõe a identificar e descrever a formação da identidade lésbica. Para tanto, propomos uma retomada das principais narrativas da experiência subjetiva do lesbianismo, a saber, do lesbianismo político ou lesbianismo radical, com as contribuições de Sheila Jeffreys e Jill Johnston, por exemplo; do pós-modernismo, a partir da leitura de Judith Butler e Paul B. Preciado; e do lesbianismo materialista, sob o prisma de Monique Wittig, Linda Alcoff e Teresa de Lauretis. Além disso, demonstraremos como o aporte teórico do lesbianismo traz uma perspectiva e contribuição importantes para os temas do feminismo, de gênero, sexualidade, performatividade e de políticas identitárias.

Resumo: Este texto tem por objetivo oferecer uma análise da cultura de estupro a partir do cognitivismo social, especialmente pela abordagem dos mecanismos de desengajamento moral desenvolvidos por Albert Bandura. Através dessa perspectiva, visamos a debater, de forma crítica, as abordagens que explicam a recorrência do estupro pelo prisma evolucionista, como a de Steven Pinker. Nossa hipótese, desenvolvida ao longo do texto, é que o estupro é um fenômeno de cunho social, consequência da permissividade legal, linguística e cultural da violência contra a mulher em contextos sociais marcados pelo machismo e pela misoginia.

This paper will unfold in two different critiques, first dealing with how neuroscience has sexed the brain, ignoring cultural elements of gender formation, and further focusing on the masculine bias of neuroscience research, which, we claim, adopts male physiological and social patterns as “normal”. In order to do so, we will start our investigation with some insights on the sex/gender debate and how it is of consequence for research on neurosciences of sexuality. Secondly, we will critic the way studies are focusing on differences rather than similarities between genders, and how such strategy re-enforces gender biases. Finally, we use contributions from social cognitivist theory and feminism to support a more complex view of body, identity and gender performance.