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• The EEG is one of the most useful technologies for brain research and clinical neurology. • The acquired traces are visibly displayed, but various studies investigate the translation of brain waves in sound. • The analog EEG was equipped with an auditory output, the pen-on-paper noise made by the writer unit, useful to facilitate the diagnosis of epileptic disorders. • Early digital EEG devices could be equipped with special software to duplicate the pen-on-paper noise digitally. • Nowadays, auditory neurofeedback has applications in therapeutic interventions, cognitive improvement, and basic research. The electroencephalogram (EEG) is one of the most useful technologies for brain research and clinical neurology, characterized by non-invasiveness and high time resolution. The acquired traces are visibly displayed, but various studies investigate the translation of brain waves in sound (i.e., a process called sonification). Several articles have been published since 1934 about the sonification of EEG traces, in the attempt to identify the "brain-sound." However, for a long time this sonification technique was not used for clinical purposes. The analog EEG was in fact already equipped with an auditory output, although rarely mentioned in scientific papers: the pen-on-paper noise made by the writer unit. EEG technologists often relied on the sound that pens made on paper to facilitate the diagnosis. This article provides a sample of analog video-EEG recordings with audio support representing the strengths of a combined visual-and-auditory detection of different types of seizures. The purpose of the present article is to illustrate how the analog EEG "sounded," as well as to highlight the advantages of this pen-writing noise. It was considered so useful that early digital EEG devices could be equipped with special software to duplicate it digitally. Even in the present days, the sonification can be considered as an attempt to modify the EEG practice using auditory neurofeedback with applications in therapeutic interventions, cognitive improvement, and basic research. [ABSTRACT FROM AUTHOR]

Abstract: Ras proteins function as a point of convergence for different signalling pathways in eukaryotes and are involved in many cellular responses; their different subcellular locations could regulate distinct functions. To investigate the localization of active Ras in vivo in Saccharomyces cerevisiae, we expressed a probe consisting of a GFP fusion with a trimeric Ras binding domain of Raf1 (eGFP-RBD3), which binds Ras-GTP with a much higher affinity than Ras-GDP. Our results show that in wild type cells active Ras accumulates mainly at the plasma membrane and in the nucleus during growth on medium containing glucose, while it accumulates mainly in mitochondria in wild type glucose-starved cells and relocalizes to the plasma membrane and to the nucleus upon addition of this sugar. A similar pattern is observed in a strain deleted in the CYR1 gene indicating that the absence of adenylate cyclase does not impair the localization of Ras-GTP. Remarkably, in a gpa2Δ, but not in a gpr1Δ mutant, active Ras accumulates in internal membranes and mitochondria, both when cells are growing on glucose medium or are starved, indicating that Gpa2, but not Gpr1 is required for the recruitment of Ras-GTP at the plasma membrane and in the nucleus. Moreover, deletion of both HXK1 and HXK2 also causes a mitochondrial localization of the probe, which relocalizes to the plasma membrane and to the nucleus upon expression of HXK2 on a centromeric plasmid, suggesting that this kinase is involved in the proper localization of active Ras. [Copyright &y& Elsevier]