Flanker effects with faces may depend on perceptual as well as emotional differences

Horstmann G, Borgstedt K, Heumann M. Flanker effects with faces may depend on perceptual as well as emotional differences. EMOTION. 2006;6(1):28-39.Do threatening or negative faces capture attention? The authors argue that evidence from visual search, spatial cuing. and flanker tasks is equivocal and that perceptual differences may account for effects attributed to emotional categories. Empirically, the authors examine the flanker task. Although they replicate previous results in which a positive face flanked by negative faces suffers more interference than a negative face flanked by positive faces, further results indicate that face perception is not necessary for the flanker-effect asymmetry and that the asymmetry also occurs with nonemotional stimuli. The authors conclude that the flanker-effect asymmetry with affective faces cannot be unambiguously attributed to emotional differences and may well be due to purely perceptual differences between the stimuli

Identification of new gene candidates on the sex chromosomes of the platyfish <em>Xiphophorus maculatus</em>

International audienceIn order to better understand the molecular and evolutionary mechanisms driving sex determination in fish, bacterial artificial chromosome (BAC) contigs covering the sex determination region of the X and Y sex chromosomes of the platyfish Xiphophorus maculatus have been constructed. Initial analysis of these contigs led to the identification of eleven gene candidates closely linked to the master sex-determining locus and expressed in different types of tissues. These genes are all present on both the X and the Y chromosomes, suggesting a restricted degree of differentiation and probably a young evolutionary age for the platyfish sex chromosomes. Syntenies were detected with several zebrafish chromosomes as well as with two medaka and several tetrapod autosomes, supporting an independent origin of sex chromosomes not only in different vertebrate lineages but also in different fish species