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The dorsal subiculum (DSub) has reciprocal connections with the dorsal hippocampus, and these regions play a role in spatial representation in contextual fear conditioning (CFC). Recently, we used AP5 and muscimol infusions to show that the DSub is required for CFC consolidation. The CFC component can be present in other learning tasks, such as step-through inhibitory avoidance (ST IA), which requires the dorsal hippocampus for acquisition and consolidation. This suggests that the DSub may be also involved in ST IA if the CFC component of the protocol is strong enough. Therefore, this study tested whether the DSub participates in ST IA acquisition and consolidation in male Wistar rats. Our data showed that pre-or posttraining infusions of AP5 or muscimol into the DSub did not affect ST IA acquisition and consolidation. We discuss the present results in relation to our previous findings, which showed the involvement of the DSub in CFC consolidation, and highlight some reasons that may explain the divergent results between the tasks. First, we note the possibility to escape from the unconditioned stimulus that occurs in ST IA, but not in CFC. We also suggest that the instrumental component of ST IA seems to be more prominent than the CFC one. Finally, we consider the possible influence of aspects of anxiety present in the ST IA, but not in CFC. These possible interpretations provide a broad framework in respect of the present results and raise new questions that demand further studies exploring the DSub function in inhibitory avoidance.

In neuroscience research, longitudinal data are often analysed using analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA) for repeated measures (rmANOVA/rmMANOVA). However, these analyses have special requirements: The variances of the differences between all possible pairs of within‐subject conditions (i.e., levels of the independent variable) must be equal. They are also limited to fixed repeated time intervals and are sensitive to missing data. In contrast, other models, such as the generalized estimating equations (GEE) and the generalized linear mixed models (GLMM), suggest another way to think about the data and the studied phenomenon. Instead of forcing the data into the ANOVAs assumptions, it is possible to design a flexible/personalized model according to the nature of the dependent variable. We discuss some advantages of GEE and GLMM as alternatives to rmANOVA and rmMANOVA in neuroscience research, including the possibility of using different distributions for the parameters of the dependent variable, a better approach for different time length points, and better adjustment to missing data. We illustrate these advantages by showing a comparison between rmANOVA and GEE in a real example and providing the data and a tutorial code to reproduce these analyses in R. We conclude that GEE and GLMM may provide more reliable results when compared to rmANOVA and rmMANOVA in neuroscience research, especially in small sample sizes with unbalanced longitudinal designs with or without missing data.

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A agressividade e a psicopatia estão relacionadas com o funcionamento do córtex pré-frontal, cuja maturação leva aproximadamente 21 anos. Assim, objetivou-se identificar a existência de diferenças entre um grupo de adolescentes, com no máximo 20 anos de idade, e um grupo de detentos no tocante ao nível de agressividade e psicopatia. Para tanto, contou-se com a participação de 48 detentos do sexo masculino, com idade média de 34,6 (DP = 8,68) e 48 adolescentes do sexo masculino, com idade média de 17,75 (DP = 1,15). Os participantes responderam ao Questionário de Agressão de Buss-Perry, a Levenson Self-Report Psychopathy scale – LSRS e o um questionário sociodemográfico. Os resultados dos testes Mann-Whitney e teste t de student indicaram a existência de diferenças significativas apenas para a psicopatia secundária, sendo mais característica em adolescentes. Os achados foram discutidos como base no desenvolvimento do Córtex Pré-Frontal nos construtos avaliados.