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See detailThe Audiospinal Reaction in Parkinsonian Patients Reflects Functional Changes in Reticular Nuclei
Delwaide, Paul ULg; PEPIN, Jean-Louis ULg; Maertens De Noordhout, Alain ULg

in Annals of Neurology (1993), 33(1), 63-9

Audiospinal facilitation using the soleus H-reflex as a test was compared in 16 control subjects and 23 parkinsonian patients. In the patients, facilitation was significantly reduced during the 75 to 150 ... [more ▼]

Audiospinal facilitation using the soleus H-reflex as a test was compared in 16 control subjects and 23 parkinsonian patients. In the patients, facilitation was significantly reduced during the 75 to 150 msec after the conditioning stimulation. This reduction was seen bilaterally even in patients with a hemisyndrome. It was corrected by L-dopa but not by anticholinergic agents. Facilitation at the 75-msec delay showed an inverse linear correlation with the bradykinesia intensity (r = -0.7, p < 0.01). The results argue in favor of a reduced excitability of the nucleus reticularis pontis caudalis from which a reticulospinal tract emanates as effector of the audiospinal facilitation. This would represent another example of dysfunction of reticular nuclei in Parkinson's disease. [less ▲]

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See detailAudiovisual reflexive methodology : How & What can be said, Where?
Stassart, Pierre M ULg; Mathieu, Valérie

Conference (2009)

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See detailAudiovisual spatial congruence, and applications to 3D sound and stereoscopic video
André, Cédric ULg

Doctoral thesis (2014)

While 3D cinema is becoming increasingly established, little effort has focused on the general problem of producing a 3D sound scene spatially coherent with the visual content of a stereoscopic-3D (s-3D ... [more ▼]

While 3D cinema is becoming increasingly established, little effort has focused on the general problem of producing a 3D sound scene spatially coherent with the visual content of a stereoscopic-3D (s-3D) movie. The perceptual relevance of such spatial audiovisual coherence is of significant interest. In this thesis, we investigate the possibility of adding spatially accurate sound rendering to regular s-3D cinema. Our goal is to provide a perceptually matched sound source at the position of every object producing sound in the visual scene. We examine and contribute to the understanding of the usefulness and the feasibility of this combination. By usefulness, we mean that the technology should positively contribute to the experience, and in particular to the storytelling. In order to carry out experiments proving the usefulness, it is necessary to have an appropriate s-3D movie and its corresponding 3D audio soundtrack. We first present the procedure followed to obtain this joint 3D video and audio content from an existing animated s-3D movie, problems encountered, and some of the solutions employed. Second, as s-3D cinema aims at providing the spectator with a strong impression of being part of the movie (sense of presence), we investigate the impact of the spatial rendering quality of the soundtrack on the reported sense of presence. The short 3D audiovisual content is presented with three different soundtracks. These soundtracks differ by their spatial rendering quality, from stereo (low spatial coherence) to Wave Field Synthesis (WFS, high spatial coherence). The original stereo version serves as a reference. Results show that the sound condition does not impact on the sense of presence of all participants. However, participants can be classified according to three different levels of presence sensitivity with the sound condition impacting only on the highest level (12 out of 33 participants). Within this group, the spatially coherent soundtrack provides a lower reported sense of presence than the other custom soundtrack. The analysis of the participants' heart rate variability (HRV) shows that the frequency-domain parameters correlate to the reported presence scores. By feasibility, we mean that a large portion of the spectators in the audience should benefit from this new technology. In this thesis, we explain why the combination of accurate sound positioning and stereoscopic-3D images can lead to an incongruence between the sound and the image for multiple spectators. Then, we adapt to s-3D viewing a method originally proposed for 2D images in the literature to reduce this error. Finally, a subjective experiment is carried out to prove the efficiency of the method. In this experiment, an angular error between an s-3D video and a spatially accurate sound reproduced through WFS is simulated. The psychometric curve is measured with the method of constant stimuli, and the threshold for bimodal integration is estimated. The impact of the presence of background noise is also investigated. A comparison is made between the case without any background noise and the case with an SNR of 4 dBA. Estimates of the thresholds and the slopes, as well as their confidence intervals, are obtained for each level of background noise. When background noise is present, the point of subjective equality (PSE) is higher (19.4° instead of 18.3°) and the slope is steeper (-0.077 instead of -0.062 per degree). Because of the overlap between the confidence intervals, however, it is not possible to statistically differentiate between the two levels of noise. The implications for the sound reproduction in a cinema theater are discussed. [less ▲]

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See detailL’audiovisuel en Belgique francophone (article sur le site internet d'Acrimed)
Geuens, Geoffrey ULg

Diverse speeche and writing (2003)

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See detailAudit du Centre d'éducation de PetroFina
Denis, Brigitte ULg

Report (1997)

Rapport de l'audit mené à la demande du centre d'éducation Petrofina.

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See detailL'audit en médecine générale : outils de dépistage et d'intervention
Filée, Dominique ULg; Gosset, Christiane ULg; Dor, B et al

Conference (2002)

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See detailAUDIT MINERALOGIQUE AU NOUVEAU CONCENTRATEUR DE KIPUSHI
Bastin, David ULg; Krier, William

Report (2004)

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See detailL'audit social. Evaluez les risques sociaux de votre entreprise !
Robert, Frédéric; Maréchal, Benoît ULg

Conference (2008, December 01)

This seminar introduce to the practice of the social audit with regard to compagnies. On basis of a list of social risks with regard to labour law and social security law, the Authors illustrated how ... [more ▼]

This seminar introduce to the practice of the social audit with regard to compagnies. On basis of a list of social risks with regard to labour law and social security law, the Authors illustrated how these risks could be examined and evaluated in the case of a social audit of the company. [less ▲]

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See detailAudition au Parlement fédéral relative à la possible instauration d'une circonscription électorale fédérale
Behrendt, Christian ULg

Conference given outside the academic context (2014)

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See detailL'audition disciplinaire du fonctionnaire
Donnay, Luc ULg

in Administration Publique [=AP] : Revue du Droit Public et des Sciences Administratives (2005), (1), 61-75

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See detailAuditory evoked potentials and multiple personality measures in migraine and post-traumatic headaches.
Wang, W.; Wang, Y.-H.; Fu, X. M. et al

in Pain (1999), 79(2-3), 235-42

Migraine sufferers have abnormal cerebral information processing and personality disorders, post-traumatic headache sufferers also have some personality changes. We therefore, studied intensity dependence ... [more ▼]

Migraine sufferers have abnormal cerebral information processing and personality disorders, post-traumatic headache sufferers also have some personality changes. We therefore, studied intensity dependence of auditory evoked potentials, Plutchik-van Praag's depression inventory, Zuckerman's sensation seeking scales and Zuckerman-Kuhlman's personality questionnaire in patients suffering from migraine without aura (n = 26) and chronic post-traumatic headaches (n = 26) as well as in healthy volunteers (n = 30). The migraine group showed significantly increased neuroticism-anxiety than controls, increased intensity dependence of N1-P2, and decreased thrill and adventure score compared with the controls and post-traumatic headaches. The post-traumatic headache had significantly increased depression compared with the controls, and increased disinhibition compared with the controls and migraines. This study demonstrates that the two headache types have different neurophysiological and personality traits. The pronounced intensity dependence of N1-P2 suggests a cortical potentiation response, together with a decreased thrill and adventure seeking, favor a lower serotonergic innervation in migraine. While the elevated disinhibition and depression, as consequences, may be linked with the wide cortical neuronal/axonal degeneration in post-traumatic headache. [less ▲]

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See detailAuditory evoked potentials in the assessment of central nervous system effects of antimigraine drugs.
Roon, K. I.; Sandor, P. S.; Schoonman, G. G. et al

in Cephalalgia : An International Journal of Headache (1999), 19(10), 880-5

Because the "intensity dependence" of cortical auditory evoked potentials (IDAP) is under serotonergic control, it can be used to assess central antimigraine effects of 5HT1B/1D agonists. We measured IDAP ... [more ▼]

Because the "intensity dependence" of cortical auditory evoked potentials (IDAP) is under serotonergic control, it can be used to assess central antimigraine effects of 5HT1B/1D agonists. We measured IDAP before and 2 h after naratriptan (5 mg, n = 19) and zolmitriptan (5 mg, n = 19) in healthy volunteers. IDAP was expressed as the amplitude-stimulus intensity function ("ASF slope"). Naratriptan tended to increase ASF slope (mean difference 0.23 +/- 0.62 microV/10 dB, p = 0.06) while zolmitriptan (0.08 +/- 0.95 microV/10 dB, p = 0.35) did not. We assessed the suitability of IDAP for measuring central antimigraine drug effects using repeatability data (see companion paper). We calculated the trade-off between the size of the expected drug effects (ASF slope difference) and the necessary sample size. Because of poor repeatability 36 to 80 subjects are required to detect ASF slope changes in the 0.25-0.5 microV/10 dB range. These data can be used to design trials using IDAP. [less ▲]

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See detailAuditory forebrain activation in the female canary is modulated by male song quality.
Barker, Jennifer ULg; Monbureau, Marie; Leboucher, Gerard et al

Poster (2010, November 17)

One of the chief functions of birdsong is to attract and stimulate females. In canaries (Serinus canaria), specific phrases (“A” phrases) sung by males have been identified as especially attractive for ... [more ▼]

One of the chief functions of birdsong is to attract and stimulate females. In canaries (Serinus canaria), specific phrases (“A” phrases) sung by males have been identified as especially attractive for females. These phrases unite a number of characteristics that are particularly difficult to combine, including large frequency bandwidth, high repetition rate and multiple-note syllables. Females exposed to “A” phrases produce more copulation displays and deposit more testosterone into their eggs. However, the neuroendocrine pathway underlying the translation of song audition to changes in testosterone deposition in yolks is not understood. Increased expression of several immediate early genes including c-fos and zenk (also called egr-1 in mammals) in other songbird species has been observed in the auditory forebrain of females hearing attractive song, and such differential activation may represent a first step in signal processing linking auditory input to egg testosterone deposition. Female canaries in breeding condition were exposed to 60 minutes of “sexy” song with a preponderance of “A” phrases, “non-sexy” song lacking “A” phrases, or white noise. Thirty minutes after the end of song playback, brains were collected, fixed in acrolein and sectioned and stained by immunohistochemistry for quantification of the Fos protein, an indicator of neuronal activity, in several regions involved in audition and auditory processing. The endocrine condition of each female was determined by measuring ovarian and oviduct weight at the time of autopsy. In the caudomedial mesopallium (CMM), Fos expression was higher in females that had heard sexy song than those that heard non-sexy song or white noise. Expression of Fos in the caudomedial nidopallium (NCM), the nucleus spiriformis medialis (SPM), the nucleus ovoidalis (OV), and the song nucleus HVC was unaffected by song quality. Thus differential auditory processing in the CMM may be an initial stage in the assessment by a female of song information to differential testosterone deposition in the egg. [less ▲]

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See detailAuditory hallucinations in schizophrenia and non-schizophrenia populations: A review and integrated model of cognitive mechanisms
Waters, F.; Aleman, A.; Fernyhough, C. et al

in Schizophrenia Bulletin (2012), 38

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See detailAuditory P300 and the altered consciousness: detecting altered states of consciousness using the P300 speller
Lulé, D.; Kleih, S.; Chatelle, Camille ULg et al

in Proceedings of TOBI Workshop 2010: Integrating Brain-Computer Interfaces with Conventional Assistive Technology (2010)

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See detailThe auditory P300-based single-switch brain–computer interface:Paradigm transition from healthy subjects to minimally consciouspatients
Pokorny, Christoph; Klobassa, Daniela; Pichler, Gerald et al

in Artificial Intelligence in Medicine (2013), 59(2), 81-90

Objective: Within this work an auditory P300 brain–computer interface based on tone stream segregation,which allows for binary decisions, was developed and evaluated.Methods and materials: Two tone ... [more ▼]

Objective: Within this work an auditory P300 brain–computer interface based on tone stream segregation,which allows for binary decisions, was developed and evaluated.Methods and materials: Two tone streams consisting of short beep tones with infrequently appearingdeviant tones at random positions were used as stimuli. This paradigm was evaluated in 10 healthysubjects and applied to 12 patients in a minimally conscious state (MCS) at clinics in Graz, Würzburg,Rome, and Liège. A stepwise linear discriminant analysis classifier with 10 × 10 cross-validation was usedto detect the presence of any P300 and to investigate attentional modulation of the P300 amplitude.Results: The results for healthy subjects were promising and most classification results were better thanrandom. In 8 of the 10 subjects, focused attention on at least one of the tone streams could be detectedon a single-trial basis. By averaging 10 data segments, classification accuracies up to 90.6 % could bereached. However, for MCS patients only a small number of classification results were above chance leveland none of the results were sufficient for communication purposes. Nevertheless, signs of consciousnesswere detected in 9 of the 12 patients, not on a single-trial basis, but after averaging of all correspondingdata segments and computing significant differences. These significant results, however, strongly variedacross sessions and conditions.Conclusion: This work shows the transition of a paradigm from healthy subjects to MCS patients. Promisingresults with healthy subjects are, however, no guarantee of good results with patients. Therefore, moreinvestigations are required before any definite conclusions about the usability of this paradigm for MCSpatients can be drawn. Nevertheless, this paradigm might offer an opportunity to support bedside clinicalassessment of MCS patients and eventually, to provide them with a means of communication. [less ▲]

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See detailAuditory processing in severely brain injured patients: differences between the minimally conscious state and the persistent vegetative state.
Boly, Mélanie ULg; FAYMONVILLE, Marie-Elisabeth ULg; Peigneux, Philippe ULg et al

in Archives of Neurology (2004), 61(2), 233-8

BACKGROUND: The minimally conscious state (MCS) is a recently defined clinical condition; it differs from the persistent vegetative state (PVS) by the presence of inconsistent, but clearly discernible ... [more ▼]

BACKGROUND: The minimally conscious state (MCS) is a recently defined clinical condition; it differs from the persistent vegetative state (PVS) by the presence of inconsistent, but clearly discernible, behavioral evidence of consciousness. OBJECTIVE: To study auditory processing among patients who are in an MCS, patients who are in a PVS, and healthy control subjects. METHODS: By means of (15)O-radiolabeled water-positron emission tomography, we measured changes in regional cerebral blood flow induced by auditory click stimuli in 5 patients in an MCS, 15 patients in a PVS, and 18 healthy controls. RESULTS: In both patients in an MCS and the healthy controls, auditory stimulation activated bilateral superior temporal gyri (Brodmann areas 41, 42, and 22). In patients in a PVS, the activation was restricted to Brodmann areas 41 and 42 bilaterally. We also showed that, compared with patients in a PVS, patients in an MCS demonstrated a stronger functional connectivity between the secondary auditory cortex and temporal and prefrontal association cortices. CONCLUSIONS: Although assumptions about the level of consciousness in severely brain injured patients are difficult to make, our findings suggest that the cerebral activity observed in patients in an MCS is more likely to lead to higher-order integrative processes, thought to be necessary for the gain of conscious auditory perception. [less ▲]

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