Semantic distance is a promising automated measure of creativity. However, it is not yet known whether semantic distance can assess creative products that are both novel and appropriate. To isolate novelty and appropriateness, participants were asked to generate a verb in response to a given noun in 3 different ways: (a) generate appropriate but not novel responses (common cue), (b) generate novel but not appropriate responses (random cue), and (c) generate responses that are both novel and appropriate (creative cue). Automated semantic distance scores and subjective ratings of creativity, novelty, and appropriateness were assessed. When participants were explicitly cued to be creative, the increased semantic distance of their responses represented increases in novelty that was constrained by an appropriateness criterion (Experiments 1 and 2). Participants cued to generate random responses had the highest semantic distance scores, but without applying the appropriateness criterion, their creativity scores suffered (Experiments 1 and 2). Additionally, participants appeared to implicitly apply the appropriateness criterion when generating creative responses (Experiment 2). In conclusion, automated measures of semantic distance can assess novel and appropriate creative responses while avoiding the pitfalls inherent to subjective ratings of creativity.

Unlike adult mammals, adult frogs regrow their optic nerve following a crush injury, making Xenopus laevis a compelling model for studying the molecular mechanisms that underlie neuronal regeneration. Using Translational Ribosome Affinity Purification (TRAP), a method to isolate ribosome-associated mRNAs from a target cell population, we have generated a transcriptional profile by RNA-Seq for retinal ganglion cells (RGC) during the period of recovery following an optic nerve injury. Based on bioinformatic analysis using the Xenopus laevis 9.1 genome assembly, our results reveal a profound shift in the composition of ribosome-associated mRNAs during the early stages of RGC regeneration. As factors involved in cell signaling are rapidly down-regulated, those involved in protein biosynthesis are up-regulated alongside key initiators of axon development. Using the new genome assembly, we were also able to analyze gene expression profiles of homeologous gene pairs arising from a whole-genome duplication in the Xenopus lineage. Here we see evidence of divergence in regulatory control among a significant proportion of pairs. Our data should provide a valuable resource for identifying genes involved in the regeneration process to target for future functional studies, in both naturally regenerative and non-regenerative vertebrates.