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Background: The relationship between sleep and creativity is a topic of much controversy. General benefits of napping have been described not only in sleep-deprived individuals and in shift workers, but also in people with sufficient night sleep. However, only few studies have investigated the relationship between nap and creativity. Methods: Forty-two native German speakers (29 females, mean age = 24 years, SD = 3.3 years) took part in two experimental sessions (i.e., baseline and intervention). In both sessions, divergent and convergent verbal and figural creativity tasks were administered at the same time of the day. While the baseline session was identical for all the participants, in the second session participants were randomized into either a sixty-minute nap or a sixty-minute rest group. Results: No significant group differences were found for neither divergent nor convergent creativity thinking tasks, suggesting that the interventions had similar effects in both groups. Interestingly, the analysis of the pooled data (i.e., pooled nap and rest groups) indicated differential effects of figural versus verbal creativity tasks, such that significant post-intervention improvements were found for the figural, but not for the verbal divergent and convergent thinking tasks. Conclusions: While further studies are needed to confirm these findings, to the best of our knowledge, such a dissociation between performance of verbal and figural creativity tasks after nap/rest interventions has not been described to date.

The paper depicts and describes the observation of a remarkable post-stroke production of paintings made by a 54-year-old, right-handed man who suffered an acute right hemispheric stroke. The patient’s post-stroke productivity and the spatial distribution of text and drawings were assessed by means of structural analysis of the paintings, as well as neuropsychological and creativity testing. Compared to the age-matched healthy control group, the patient did not only produce more valid answers in the verbal creativity task, but he also drew more images in the figural creativity task. Most strikingly, the painted images were located on the right side in 70% of the paintings, while the text was aligned to the left side in 42% of the paintings. This dissociation between writing and painting behavior was further mirrored in the patient’s neuropsychological performance in a reading test and in a design fluency task. This observation of an increased post-stroke production of paintings may coin a new term, i.e., “hyperzographia”, in analogy to hypergraphia. Additionally, the puzzling dissociation of the writing and painting behavior highlights an important new clinical aspect concerning a differential influence of hemispatial neglect on writing and painting.

Application of silica nanoparticles (SiO2-NPs) may result in human exposure. Here we investigate unexplored modes of action by which SiO2-NPs with average size of 225 nm act on human hepatoma cells (Huh7). We focused on the endoplasmic (ER) stress response and on mitogen-activated protein kinase (MAPK) signaling pathways. Both pathways were induced. ER stress and the associated three unfolded protein response (UPR) pathways were activated as demonstrated by significant inductions of BiP and XBP-1s and a moderate but significant induction of ATF-4 at 0.05 and 0.5 mg/ml. In addition to activation of NFкB interferon stimulated genes IP-10, IRF-9, and ISG-15 were up-regulated. As a consequence of ER stress, the pro-inflammatory cytokine TNFα and PP2Ac were induced following exposure to 0.05 mg/ml SiO2-NPs. Additionally, this occurred at 0.005 mg/ml SiO2-NPs for TNFα at 24 h. This in turn led to a strong transcriptional induction of MAP-kinases and its target genes cJun, cMyc and CREB. A strong transcriptional down-regulation of the proapoptotic gene p53 occurred at 0.05 and 0.5 mg/ml SiO2-NP. Exposure of Huh7 cells to the anti-oxidant N-acetyl cysteine reduced transcriptional induction of ER stress markers demonstrating a link between the induction of oxidative stress and ER stress. Our study demonstrates that SiO2-NPs lead to strong ER stress and UPR induction, oxidative stress, activation of MAPK signaling and down-regulation of p53. All of these activated pathways, which are analyzed here for the first time in detail, inhibit apoptosis and induce cell proliferation, which may contribute to a hepatotoxic, inflammatory and tumorigenic action of SiO2-NPs.