Synesthesia and memory: an exploratory analysis

Few studies have measured how the memory of individuals with synesthesia, a perceptual phenomenon in which a stimulus triggers a separate sensory experience, is affected because of their novel perceptual experiences. The studies that have examined synesthesia and enhanced memory have been inconclusive, as some have found those with synesthesia exhibit superior memory capabilities, while other studies have not. This study sought to replicate previous studies that have found effects of color congruency. The participant M.P., a female with grapheme-color synesthesia, was given lists of words that were either congruent to her synesthetic experience, random colors, or words in black ink, then tested over her memory for the lists. Results were then compared to mean scores of a control group (n = 15). Results indicate a deviation from the hypothesis, as M.P. did not exhibit superior memory for congruent information, but rather a potentially enhanced ability to suppress color information

Phenotype ontologies and cross-species analysis for translational research

The use of model organisms as tools for the investigation of human genetic variation has significantly and rapidly advanced our understanding of the aetiologies underlying hereditary traits. However, while equivalences in the DNA sequence of two species may be readily inferred through evolutionary models, the identification of equivalence in the phenotypic consequences resulting from comparable genetic variation is far from straightforward, limiting the value of the modelling paradigm. In this review, we provide an overview of the emerging statistical and computational approaches to objectively identify phenotypic equivalence between human and model organisms with examples from the vertebrate models, mouse and zebrafish. Firstly, we discuss enrichment approaches, which deem the most frequent phenotype among the orthologues of a set of genes associated with a common human phenotype as the orthologous phenotype, or phenolog, in the model species. Secondly, we introduce and discuss computational reasoning approaches to identify phenotypic equivalences made possible through the development of intra- and interspecies ontologies. Finally, we consider the particular challenges involved in modelling neuropsychiatric disorders, which illustrate many of the remaining difficulties in developing comprehensive and unequivocal interspecies phenotype mappings

A possible dearth of hot gas in galaxy groups at intermediate redshift

We examine the X-ray luminosity of galaxy groups in the CNOC2 survey, at redshifts 0.1 < z < 0.6. Previous work examining the gravitational lensing signal of the CNOC2 groups has shown that they are likely to be genuine, gravitationally bound objects. Of the 21 groups in the field of view of the EPIC-PN camera on XMM-Newton, not one was visible in over 100 ksec of observation, even though three of the them have velocity dispersions high enough that they would easily be visible if their luminosities scaled with their velocity dispersions in the same way as nearby groups' luminosities scale. We consider the possibility that this is due to the reported velocity dispersions being erroneously high, and conclude that this is unlikely. We therefore find tentative evidence that groups at intermediate redshift are underluminous relative to their local cousins.Comment: 16 pages, 5 figures, reference added in section 1, typos corrected, published in Ap

Mechanisms of Astrocyte Contribution to Bortezomib-Induced Peripheral Neuropathy

Bortezomib is a proteasome inhibitor used in the treatment of multiple myeloma and other non-solid malignancies, alone or in combination with other chemotherapy drugs. Like other chemotherapeutic agents, bortezomib treatment is frequently accompanied by chemotherapy-induced peripheral neuropathy (CIPN) that may be dose-limiting, adversely affecting quality of life and prognosis. The mechanisms behind bortezomib-induced peripheral neuropathy (BIPN) and CIPN overall are largely unknown. Recent findings in other pain models have indicated substantial involvement of glial cells in chronic pain. Although injury models have shown activation of both astrocytes and microglia following insult, research in other CIPN models has shown astrocytic activation in the absence of microglial activation. The central hypothesis of this dissertation is that the activity of astrocytes is correlated with behavioral changes observed in a rat model of BIPN in a manner that may directly contribute to these changes in behavior. To investigate this, the work of this dissertation 1) established the multimodal changes to behavior and showed increases in spinal neuron firing in BIPN, 2) quantified activity of astrocytes and whether changes were prevented by minocycline, an anti-inflammatory drug that vi prevents glial activation, and 3) quantified changes in connexin 43, GLT-1, and GLAST to assess whether astrocytic glutamate transport may be altered in BIPN. The results observed in the first aim were that the rat BIPN model is characterized by selective mechanical hypersensitivity and a significant increase in wide dynamic range (WDR) neuron firing rates and after-discharges. In the second aim, astrocytes in the BIPN model were activated in a manner that paralleled the behavioral changes. Animals co-treated with minocycline resembled saline-treated animals in both astrocytic activation and behaviors. The results in the third aim were that astrocytic gap junctions were increased and GLAST expression was decreased at the height of mechanical sensitivity. Minocycline-treated animals resembled saline-treated animals in expression of these proteins, as well. The overall conclusion was that astrocyte activity closely paralleled behaviors in the BIPN model in a manner that may be explained by their role in glutamate trafficking