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 We examined the interaction between MS and ΝΗΙ on emotionality and markers of plasticity. Both MS and NHI increased anxiety levels, but only NHI induced depressionlike behavior. Maternal separation did not further increase emotionality in HI-treated rats. Both MS and NHI decreased synaptophysin levels in dentate gyrus and CA3 hippocampal areas. BDNF expression in CA3 was decreased only in the HI animals that were maternally-separated. AbstractExposure to early-life stress is associated with long-term alterations in brain and behavior, and may aggravate the outcome of neurological insults. This study aimed at investigating the possible interaction between maternal separation, a model of early stress, and subsequent neonatal hypoxia-ischemia on emotional behavior and markers of synaptic plasticity in hippocampus. Therefore, rat pups (N=60) were maternally separated for a prolonged (MS 180min) or a brief (MS 15min) period during the first six postnatal days, while a control group was left undisturbed. Hypoxia-ischemia was applied to a subgroup of each rearing condition on postnatal day 7. Emotional behavior was examined at three months of age and included assessments of anxiety (elevated plus maze), depression-like behavior (forced swimming) and spontaneous exploration (open field). Synaptic plasticity was evaluated based on BDNF and synaptophysin expression in CA3 and dentate gyrus hippocampal regions. We found that neonatal hypoxia-ischemia caused increased levels of anxiety, depression-like behavior and locomotor activity (ambulation). Higher anxiety levels were also seen in maternally separated rats (MS180min) compared to non-maternally separated rats, but prolonged maternal separation prior to HI did not potentiate the HI-associated effect. No differences among the three rearing conditions were found regarding depression-like behavior or ambulation. Immunohistochemical evaluation of synaptophysin revealed that both prolonged maternal separation (MS180min) and neonatal hypoxia-ischemia significantly reduced its expression in the CA3 and dentate gyrus. Decreases in synaptophysin expression in these areas were not exacerbated in rats that were maternally separated for a prolonged period prior to HI. Regarding BDNF expression, we found a significant decrease in immunoreactivity only in the hypoxic-ischemic rats that were subjected to the prolonged maternal separation paradigm. The above findings suggest that early-life stress prior to neonatal hypoxia-ischemia leads to significant alterations in synaptic plasticity of the dorsal hippocampus during adulthood, but does not exacerbate HI-related changes in emotional behavior.

We describe the case of a patient with bilateral thalamic lesions due to brain infarcts in the paramedian thalamic artery territories. The patient demonstrated symptoms of apathy (e.g., loss of initiative and interest in others, poor motivation, flattened affect). Neuropsychological assessment 3 and 5 years post-infarct revealed severe deficits in verbal and non-verbal immediate and delayed memory, attention, and executive functioning, with minimal improvement over time. Also, he demonstrated difficulties in social cognition (i.e., perception of facial expressions of others and of sarcasm). These findings are discussed and interpreted in light of current theories regarding the neurobiological substrate of apathy.

Scaffolds are considered to be a promising method of supporting learning. In this study, we investigated the learning efficacy of scaffolds in an inquiry-based learning scenario. Three tasks posed a question/problem to facilitate inquiry-based learning, and scaffolds offered the answer/solution in multiple steps (so-called incremental scaffolds). The use of the scaffolds was voluntary and students’ learning efficacy was compared with a traditional teaching approach. A total of N = 105 seventh graders participated in the quasi-experimental study. Incremental scaffolds were available to the students in the treatment group. Students in the control group received the same question/problem but could only ask the teacher about the answer/solution. Concept maps were used at pre- and posttest to assess conceptual knowledge acquisition. In-line with our hypothesis, results show that students in the treatment group outperformed controls concerning conceptual knowledge acquisition. Regarding the number of misconceptions students used, there were no differences between the groups. Our study indicates that incremental scaffolds are an appropriate method to provide students with the exact help they really need. Based on our findings, we offer practical implications and recommendations for future research.

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