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Abstract: Zebrafish is gaining popularity in basic behavioral brain research, behavior genetics, and in translational studies because it offers a cheap and efficient alternative to rodents. Abnormally exaggerated fear and anxiety are some of the most prevalent neuropsychiatric diseases in the human society whose mechanisms are not well understood. These diseases still represent major unmet medical needs. Ethologically relevant fear paradigms involving the presentation of predators, or of stimuli characteristic of predators, have been proposed as appropriate for the modeling and the analysis of fear responses. Previously, we have shown that zebrafish respond specifically to visual stimuli of their sympatric predator, the Indian leaf fish. In the current paper we show that an animated (moving) image of this predator elicits significant behavioral responses and that these responses can be quantified using video-tracking. As stimulus presentation and behavioral response quantification are both computerized and automated, we suggest the paradigm is appropriate for high throughput screening and, once pharmacologically and behaviorally validated, may have utility in the detection of anxiolytic or anxiogenic properties of compounds or in the identification of fear altering mutations. [Copyright &y& Elsevier]

Abstract: Spatial learning abilities of rodents have been extensively used to explore the management of a wide range of cognitive and emotional processes such as learning, memory, attention and anxiety. Knowledge about the organization and processing of spatial learning has mainly been obtained in rats. Due to increasing generation of genetically modified mice, cognitive abilities of mice are now extensively tested. The present paper aimed at comparing spatial representation, learning and strategies in C57BL/6J mice and Long-Evans Hooded rats when subjected to the same spatial learning paradigm, i.e. learning a food location in a crossmaze. We also analyzed the influence of environmental richness on learning modalities in both species. Our results showed that rats and mice could exhibit similar spatial learning abilities in some circumstances. However, Long-Evans rats and C57BL/6J mice may set up different strategies depending on the availability of visual information within the environment. Rats’ learning strategies mainly relied on distant visual cues and seemed more efficient than those used by mice as they needed less time than mice to solve the task. We emphasize that the strategies of mice are less robust and flexible than the ones set up by rats. Finally, the richness of the environment was shown to affect speed and quality of spatial learning in both species. [Copyright &y& Elsevier]

Abstract: Low sociability is one of the most prominent and disabling symptoms of autism. The biology of sociability is not well understood, and there is no available treatment that adequately improves social functioning in most autistic patients. The development of animal models of reduced sociability can aid in the elucidation of the biology of social behaviors, and may ultimately shed light on the biology of autism. This paper will review evidence that mice of the BALB/c inbred strain show relatively low levels of social interaction in various settings and across various stages of development, including male–male interactions, female–female interactions, male–female sexual interactions, and parenting behaviors. Taken together, this evidence suggests a generally low level of sociability in BALB/c mice that may be relevant to autism. BALB/c mice also show other phenotypes with possible relevance to autism, including relatively high levels of anxiety and aggressive behaviors, large brain size, underdevelopment of the corpus callosum, and low levels of brain serotonin. Further research is needed to determine the relationship among these BALB/c phenotypes, and to determine their possible relevance to autism. In conclusion, the BALB/c inbred strain may be a useful animal model for identifying genes and neurobiological pathways involved in autism-related phenotypes. [Copyright &y& Elsevier]

The general hypothesis underlying this paper is that behavior in traditional paradigms of laboratory learning is based on niche-related mechanisms. The specific hypothesis is that the behavior of Norway rats in laboratory mazes is based on niche-related mechanisms related to trail following and navigating. I evaluate seven types of evidence for this hypothesis: (a) resemblance of maze behavior to behavior in unconstrained settings; (b) importance of experimenter tuning of apparatus and procedures; (c) overdetermination of laboratory behavior; (d) reverse-engineering of niche-related mechanisms from laboratory data; (e) prediction of laboratory results from ecological data; (f) contribution of specific relative to general mechanisms; and (g) phylogenetic conservation and ecologically-based convergence and divergence of maze mechanisms. I conclude there is strong evidence for the hypothesis that behavior of rats in laboratory mazes is based on niche-related mechanisms. I suggest that a niche-related approach to laboratory learning paradigms has conceptual generality and the potential to facilitate connections with the study of neurophysiology, genetics, and evolution. [Copyright &y& Elsevier]