Alpha Rhythms in Audition: Cognitive and Clinical Perspectives

Like the visual and the sensorimotor systems, the auditory system exhibits pronounced alpha-like resting oscillatory activity. Due to the relatively small spatial extent of auditory cortical areas, this rhythmic activity is less obvious and frequently masked by non-auditory alpha-generators when recording non-invasively using magnetoencephalography (MEG) or electroencephalography (EEG). Following stimulation with sounds, marked desynchronizations can be observed between 6 and 12 Hz, which can be localized to the auditory cortex. However knowledge about the functional relevance of the auditory alpha rhythm has remained scarce so far. Results from the visual and sensorimotor system have fuelled the hypothesis of alpha activity reflecting a state of functional inhibition. The current article pursues several intentions: (1) Firstly we review and present own evidence (MEG, EEG, sEEG) for the existence of an auditory alpha-like rhythm independent of visual or motor generators, something that is occasionally met with skepticism. (2) In a second part we will discuss tinnitus and how this audiological symptom may relate to reduced background alpha. The clinical part will give an introduction into a method which aims to modulate neurophysiological activity hypothesized to underlie this distressing disorder. Using neurofeedback, one is able to directly target relevant oscillatory activity. Preliminary data point to a high potential of this approach for treating tinnitus. (3) Finally, in a cognitive neuroscientific part we will show that auditory alpha is modulated by anticipation/expectations with and without auditory stimulation. We will also introduce ideas and initial evidence that alpha oscillations are involved in the most complex capability of the auditory system, namely speech perception. The evidence presented in this article corroborates findings from other modalities, indicating that alpha-like activity functionally has an universal inhibitory role across sensory modalities

Top-Down Modulation of the Auditory Steady-State Response in a Task-Switch Paradigm

Auditory selective attention is an important mechanism for top-down selection of the vast amount of auditory information our perceptual system is exposed to. In the present study, the impact of attention on auditory steady-state responses is investigated. This issue is still a matter of debate and recent findings point to a complex pattern of attentional effects on the auditory steady state response (aSSR). The present study aimed at shedding light on the involvement of ipsilateral and contralateral activations to the attended sound taking into account hemispheric differences and a possible dependency on modulation frequency. In aid of this, a dichotic listening experiment was designed using amplitude-modulated tones that were presented to the left and right ear simultaneously. Participants had to detect target tones in a cued ear while their brain activity was assessed using MEG. Thereby, a modulation of the aSSR by attention could be revealed, interestingly restricted to the left hemisphere and 20 Hz responses: contralateral activations were enhanced while ipsilateral activations turned out to be reduced. Thus, our findings support and extend recent findings, showing that auditory attention can influence the aSSR, but only under specific circumstances and in a complex pattern regarding the different effects for ipsilateral and contralateral activations

Life Science Zurich Learning Center – A New Symbiosis of Research Institutions and Schools

The Life Science Learning Center (LSLC) was officially founded in 2005. It is a branch of the pre-existing Life Science Zurich, an organization created by and belonging to the University of Zurich and the Swiss Federal Institute of Technology Zurich to promote and support life sciences in several central parts of society. The LSLC's primary goals are to offer educational opportunities for school children as well as continuing education for teachers of the primary and secondary school levels. In particular, the LSLC facilitates various types of interactions between schools and the higher educational and research institutions (University of Zurich and Federal Institutes of Technology): it offers practicals for pupils in a special laboratory, tours of professional research laboratories, pedagogical training for future biology teachers, and specialized modules of continuing education for teachers. It also contributes to diverse initiatives promoting life sciences in the general public. It is led by a small team of dedicated people based on the Irchel Campus of the University of Zurich

Percepções de acadêmicos e equipe de enfermagem sobre o projeto de extensão: “Caminhando pelo hospital”

Objetivo: Conhecer a percepção de acadêmicos(as) e equipe de enfermagem sobre o projeto de extensão “Caminhando pelo hospital”.Método: Estudo qualitativo realizado em hospital universitário brasileiro de novembro/2019 a abril/2022 com acadêmicos e profissionais de enfermagem participantes de um projeto de extensão universitária. Os dados foram coletados por meio de instrumentos na plataforma Google Forms® e submetidos à Análise da Temática de Conteúdo. Projeto aprovado pelo Comitê de Ética.Resultados: Participaram do estudo 15 acadêmicos, quatro enfermeiros e seis técnicos de enfermagem. Da análise, emergiram quatro categorias: “Conhecendo o ambiente/dinâmica hospitalar”, “Articulação entre teoria e prática”, “Vínculo entre acadêmicos e profissionais da saúde” e “Processo de trabalho da unidade”.Considerações finais: Os achados evidenciam a importância da extensão universitária ao   proporcionar conhecimentos e experiências da prática clínica hospitalar, o que pode contribuir no fortalecimento do ensino e da formação acadêmica em enfermagem.Palavras-chave: Hospitais universitários. Estudantes de enfermagem. Educação em enfermagem. Relações comunidade-instituição

A Moral Dilemma for the Political Psychologist: Decreasing Criminal Violence as Symptom

This article describes two approaches to decreasing criminal violence and the moral dilemma in choosing between them

Demonstration and STEM Analysis of Ferroelectric Switching in MOCVD-Grown Single Crystalline Al0.85_{0.85}Sc0.15_{0.15}N

Wurtzite-type Al$_{1-x}$Sc$_x$N solid solutions grown by metal organic chemical vapour deposition are for the first time confirmed to be ferroelectric. The film with 230 nm thickness and x = 0.15 exhibits a coercive field of 5.5 MV/cm at a measurement frequency of 1.5 kHz. Single crystal quality and homogeneous chemical composition of the film was confirmed by X-ray diffraction spectroscopic methods such as time of flight secondary ion mass spectrometry. Annular bright field scanning transmission electron microscopy served to proof the ferroelectric polarization inversion on unit cell level. The single crystal quality further allowed to image the large-scale domain pattern of a wurtzite-type ferroelectric for the first time, revealing a predominantly cone-like domain shape along the c-axis of the material. As in previous work, this again implies the presence of strong polarization discontinuities along this crystallographic axis, which could be suitable for current transport. The domains are separated by narrow domain walls, for which an upper thickness limit of 3 nm was deduced, but which could potentially be atomically sharp. We are confident that these results will advance the commencing integration of wurtzite-type ferroelectrics to GaN as well as generally III-N based heterostructures and devices.Comment: 5 Figure

The effects of midazolam on intraocular pressure in children during examination under sedation

Background: To obtain reliable and accurate measurements of the intraocular pressure (IOP) in children often requires sedation or anaesthesia. Therefore, we investigated the effects of oral midazolam on IOP in children. Methods: In a prospective study, IOP was measured in 72 eyes of 36 cooperative children without glaucoma requiring general anaesthesia (mean age 3.5±1.3 years, body weight ≤20 kg) by using a Perkins hand-held tonometer. Measurements of IOP were performed before, and 15 and 30 min after sedation with orally administered midazolam (1 mg/kg) given as preoperative medication, and 5 and 15 min after induction of general anaesthesia. The individual IOP courses were analysed. Results: In all of the cooperative children, IOP measurement was possible after sedation with midazolam. Mean IOP was 11.2±0.3 mmHg before sedation, 10.9±0.2 mmHg at 15 min, and 10.7±0.3 mmHg 30 min after administration of midazolam. This small decrease was not statistically significant, whilst the IOP decline at 5 and 15 min after induction of general anaesthesia was statistically significant (p<0.0001). Conclusion: Sedation with midazolam can be assumed to be an applicable, well-tolerated, safe method for IOP measurements in children

Glass powder doping of nanocrystal-doped fibres: challenges and results

Incorporating new optical materials as nanocrystals into glass fibres for new functionalities has recently become a hot research topic. Our team (funded by the European FET Open project NCLAS) investigates the introduction of nanoscale laser crystallites into the core of optical fibres using the glass powder doping method. Active Y2O3:Pr3+ nanocrystals (NCs) were prepared via different synthesis methods, and structurally and spectroscopically characterized. After modification of technological parameters, the optimised NCs have been proposed as a luminescence centres to embed into germanate and silicate glass hosts. Glasses were analysed in terms of optical (transmission, refractive index matching to NCs) and thermal (thermal stability, viscosity, thermal expansion coefficient) parameters. Crystallisation issues during fibre drawing were particularly investigated. In a first step, glass powder-NCs mixing techniques and fibre preform preparation were developed. It was shown that temperature cycle profiles including dwell time and heating/cooling ramp rates influenced the glass-NCs properties and can lead to glass crystallisation or NCs dissolution. The sintering investigations pointed out the melting temperature limits to preserve active NCs in the glasses. In germanate glasses, Y2O3:Pr3+ dissolution was noticed at 800°C. In the case of the silicate glass compositions these regions vary from 700°C to 1050°C. The results allowed to select optical fibre drawing conditions performed by the powder-in-tube method. Their distribution uniformity is not yet sufficient, requiring further optimisation of the drawing kinetics.The research project funded by the European FET Open project NCLas: NanoCrystals in Fibre Lasers, Grant agreement number: 82916