Measures of Anxiety in Zebrafish (Danio rerio): Dissociation of Black/White Preference and Novel Tank Test

The effects of wall color stimuli on diving, and the effects of depth stimuli on scototaxis, were assessed in zebrafish. Three groups of fish were confined to a black, a white, or a transparent tank, and tested for depth preference. Two groups of fish were confined to a deep or a shallow tank, and tested for black-white preference. As predicted, fish preferred the deep half of a split-tank over the shallow half, and preferred the black half of a black/white tank over the white half. Results indicated that the tank wall color significantly affected depth preference, with the transparent tank producing the strongest depth preference and the black tank producing the weakest preference. Tank depth, however, did not significantly affect color preference. Additionally, wall color significantly affected shuttling and immobility, while depth significantly affected shuttling and thigmotaxis. These results are consistent with previous indications that the diving response and scototaxis may reflect dissociable mechanisms of behavior. We conclude that the two tests are complementary rather than interchangeable, and that further research on the motivational systems underlying behavior in each of the two tests is needed

Las situaciones de alfabetización temprana en hogares de dos grupos sociales de Argentina

296 Literacy development experiences of 20 four-year-old children from middle socio economical level and 20 four-year-old underclass children are analyzed. Both group experiences were compared according to type, structure and interaction between participants. A qualitative procedure was used (Strauss & Corbin, 1991).Differences regarding type and number of experiences in each group were identified. Children in both groups showed equal interest regarding reading and writing.En el marco de las perspectivas socioculturales actuales (Nelson, 2010) y en las líneas de investigación de alfabetización temprana y familiar (Hannon & Bird, 2004), se analizan 296 situaciones de alfabetización registradas en hogares de 20 niños de 4 años de poblaciones urbano marginadas y 20 niños de sectores medios. Empleando un procedimiento cualitativo (Strauss & Corbin, 1991) se analizaron comparativamente las situaciones registradas en ambos grupos atendiendo al tipo y a la estructura de la situación y a la interacción entre los participantes. Se identificaron diferencias en el tipo y la cantidad de situaciones en las que participaron los niños de ambos grupos. No se observaron diferencias en el interés de los niños por la lectura y la escritura

Comparative Analyses of Zebrafish Anxiety-Like Behavior Using Conflict-Based Novelty Tests

Modeling of stress and anxiety in adult zebrafish (Danio rerio) is increasingly utilized in neuroscience research and central nervous system (CNS) drug discovery. Representing the most commonly used zebrafish anxiety models, the novel tank test (NTT) focuses on zebrafish diving in response to potentially threatening stimuli, whereas the light-dark test (LDT) is based on fish scototaxis (innate preference for dark vs. bright areas). Here, we systematically evaluate the utility of these two tests, combining meta-analyses of published literature with comparative in vivo behavioral and whole-body endocrine (cortisol) testing. Overall, the NTT and LDT behaviors demonstrate a generally good cross-test correlation in vivo, whereas meta-analyses of published literature show that both tests have similar sensitivity to zebrafish anxiety-like states. Finally, NTT evokes higher levels of cortisol, likely representing a more stressful procedure than LDT. Collectively, our study reappraises NTT and LDT for studying anxiety-like states in zebrafish, and emphasizes their developing utility for neurobehavioral research. These findings can help optimize drug screening procedures by choosing more appropriate models for testing anxiolytic or anxiogenic drugs