Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power

<p>Abstract</p> <p>Background</p> <p>Tinnitus is an auditory phantom phenomenon characterized by the sensation of sounds without objectively identifiable sound sources. To date, its causes are not well understood. Previous research found altered patterns of spontaneous brain activity in chronic tinnitus sufferers compared to healthy controls, yet it is unknown whether these abnormal oscillatory patterns are causally related to the tinnitus sensation. Partial support for this notion comes from a neurofeedback approach developed by our group, in which significant reductions in tinnitus loudness could be achieved in patients who successfully normalized their patterns of spontaneous brain activity. The current work attempts to complement these studies by scrutinizing how modulations of tinnitus intensity alter ongoing oscillatory activity.</p> <p>Results</p> <p>In the present study the relation between tinnitus sensation and spontaneous brain activity was investigated using residual inhibition (RI) to reduce tinnitus intensity and source-space projected magnetencephalographic (MEG) data to index brain activity. RI is the sustained reduction (criteria: 50% for at least 30 s) in tinnitus loudness after cessation of a tonal tinnitus masker. A pilot study (n = 38) identified 10 patients who showed RI. A significant reduction of power in the delta (1.3–4.0 Hz) frequency band was observed in temporal regions during RI (p ≤ 0.001).</p> <p>Conclusion</p> <p>The current results suggest that changes of tinnitus intensity induced by RI are mediated by alterations in the pathological patterns of spontaneous brain activity, specifically a reduction of delta activity. Delta activity is a characteristic oscillatory activity generated by deafferented/deprived neuronal networks. This implies that RI effects might reflect the transient reestablishment of balance between excitatory and inhibitory neuronal assemblies, via reafferentation, that have been perturbed (in most tinnitus individuals) by hearing damage. As enhancements have been reported in the delta frequency band for tinnitus at rest, this result conforms to our assumption that a normalization of oscillatory properties of cortical networks is a prerequisite for attenuating the tinnitus sensation. For RI to have therapeutic significance however, this normalization would have to be stabilized.</p

Registro de movimientos oculares con el eye tracker Mobile eye XG

93 p.Debido a su importancia en la investigación sobre lo que sucede en el cerebro, el estudio sobre el sistema visual humano se ha especializado cada vez más para indagar sobre la influencia de los movimientos oculares en la percepción durante la observación. Con el fin de acceder a este tipo de procesos se ha diseñado un conjunto de herramientas que permiten hacer un seguimiento a los movimientos oculares, conocidos como eye trackers. Este libro tiene como objetivo aportar elementos para la planeación, el diseño y la ejecución de investigaciones que incluya el uso de eye trackers, en particular del eye tracker Mobile eye XG. Esta es una de las primeras revisiones en español que recopila información sobre los movimientos oculares. Contiene una descripción sobre el eye tracker Mobile eye XG y otros dispositivos; una revisión sobre la visión humana y los movimientos oculares; una reseña acerca de los determinantes cognoscitivos de los movimientos oculares; una aproximación a las condiciones para el diseño, la ejecución y el análisis de datos de las investigaciones con esta herramienta y una revisión sobre sus campos de aplicación.Technological advances in recent decades have made eye trackers, especially glasses, an important tool in the field of cognitive, emotional, and social neurosciences, due to the relationship that exists between visual behavior and neuronal processes. This has facilitated the study of a significant number of psychological processes, including perception, emotions, social cognition, decision making, attention, and literacy, among others. Eye trackers have been applied to research a wide range of human activities, including web page and application design and market studies, the visual behavior of drivers and athletes, human-computer interactions, simulations for military training, and as a support for the clinical diagnosis of personality disorders and neurological conditions. This book aims to provide elements for the planning, design, and execution of research that includes the use of eye trackers, in particular the Mobile Eye-XG eye tracker. This is one of the first reviews in Spanish that collects information on eye movements. The study contains a description of the Mobile Eye-XG eye tracker and other devices; a review of human vision and eye movements; a review of the cognitive determinants of eye movements; an exploration of the conditions that determine the design, execution, and data analysis of research that uses this tool, as well as a review of its fields of application.Introducción Parte 1. Descripción del eye tracker Mobile eye XG Parte 2. Visión humana y movimientos oculares Parte 3. Neurobiología de los movimientos oculares Parte 4. Determinantes cognoscitivos de las fijaciones y de los movimientos oculares Parte 5. Condiciones para el diseño y el registro de estudios con el eye tracker Mobile eye XG Parte 6. Análisis y representación gráfica de los datos Parte 7. Condiciones para el reporte de investigación Parte 8. Aplicaciones del eye tracking Referencias Anexo

Entwicklung eines Dokumentationskonzepts und einer asynchronen Kommunikationsstruktur für ein Fußgänger-Simulationssystem im Rahmen des WALK-Projekts

Diese Arbeit beschreibt die Umsetzung der Kommunikationsstruktur eines Fußgängersimulationsystems. Im Rahmen dieser Entwicklung wird ein Dokumentationskonzept für die Software- Architektur dieses Systems ausgewählt und an die individuellen Anforderungen des Projekts angepasst. Es werden mehrere nachrichtenbasierte Middleware-Produkte untersucht und bewertet.This thesis describes the implementation of the communication systeme for a pedestrian simulationsystem. In this context a documentation concept for the software-architecture of the simulationsystem is choosen and Vtted to the special needs of the project. DiUerent message oriented middleware products are analysed and evaluated in this work

THE EFFECTS OF SOME DEVELOPMENTAL INHIBITORS ON THE PHOSPHORUS BALANCE OF AMPHIBIAN GASTRULAE

Volume: 113Start Page: 376End Page: 38

Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power-2

<p><b>Copyright information:</b></p><p>Taken from "Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power"</p><p>http://www.biomedcentral.com/1741-7007/6/4</p><p>BMC Biology 2008;6():4-4.</p><p>Published online 16 Jan 2008</p><p>PMCID:PMC2254377.</p><p></p>for every subject pre- and post-stimulation. One line represents one subject. The thick grey lines indicate the mean tinnitus loudness over all subjects. CO and RI conditions are shown separately. Please note that due to a decrease in tinnitus loudness over the course of the experiment, in some subjects the mean pre-tinnitus loudness is not 10 for every subject

Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power-0

<p><b>Copyright information:</b></p><p>Taken from "Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power"</p><p>http://www.biomedcentral.com/1741-7007/6/4</p><p>BMC Biology 2008;6():4-4.</p><p>Published online 16 Jan 2008</p><p>PMCID:PMC2254377.</p><p></p>for every subject pre- and post-stimulation. One line represents one subject. The thick grey lines indicate the mean tinnitus loudness over all subjects. CO and RI conditions are shown separately. Please note that due to a decrease in tinnitus loudness over the course of the experiment, in some subjects the mean pre-tinnitus loudness is not 10 for every subject

Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power-1

<p><b>Copyright information:</b></p><p>Taken from "Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power"</p><p>http://www.biomedcentral.com/1741-7007/6/4</p><p>BMC Biology 2008;6():4-4.</p><p>Published online 16 Jan 2008</p><p>PMCID:PMC2254377.</p><p></p>arately. Each line represents a single subject. The thick grey lines indicate the mean delta band activities over all subjects

Pre- and post-stimulus alpha activity shows differential modulation with spatial attention during the processing of pain.

Extensive work using magneto- and electroencephalography (M/EEG) suggests that cortical alpha activity represents a top-down controlled gating mechanism employed by processes like attention across different modalities. However, it is not yet clear to what extent this presumed gating function of alpha activity also applies to the processing of pain. In the current study, a spatial attention paradigm was employed requiring subjects to attend to painful laser stimuli on one hand while ignoring stimuli on the other hand. Simultaneously, brain activity was recorded with MEG. In order to disentangle pre- and post-stimulus effects of attention, alpha activity was analyzed during time windows in anticipation of and in response to painful laser stimulation. Painful laser stimuli led to a suppression of alpha activity over both ipsi- and contralateral primary somatosensory areas irrespective if they were attended or ignored. Spatial attention was associated with a lateralization of anticipatory pre-stimulus alpha activity. Alpha activity was lower over primary somatosensory areas when the contralateral hand was attended compared to when the ipsilateral hand was attended, in line with the notion that oscillatory alpha activity regulates the flow of incoming information by engaging and/or disengaging early sensory areas. On the contrary, post-stimulus alpha activity, for stimuli on either hand, was consistently decreased with attention over contralateral areas. Most likely, this finding reflects an increased cortical activation and enhanced alerting if a painful stimulus is attended. The present results show that spatial attention results in a modulation of both pre- and post-stimulus alpha activity associated with pain. This flexible regulation of alpha activity matches findings from other modalities. We conclude that the assumed functional role of alpha activity as a top-down controlled gating mechanism includes pain processing and most likely represents a unified mechanism used throughout the brain