75 research outputs found
Electrophysiological differences and similarities in audiovisual speech processing in CI users with unilateral and bilateral hearing loss.
Hearing with a cochlear implant (CI) is limited compared to natural hearing. Although CI users may develop compensatory strategies, it is currently unknown whether these extend from auditory to visual functions, and whether compensatory strategies vary between different CI user groups. To better understand the experience-dependent contributions to multisensory plasticity in audiovisual speech perception, the current event-related potential (ERP) study presented syllables in auditory, visual, and audiovisual conditions to CI users with unilateral or bilateral hearing loss, as well as to normal-hearing (NH) controls. Behavioural results revealed shorter audiovisual response times compared to unisensory conditions for all groups. Multisensory integration was confirmed by electrical neuroimaging, including topographic and ERP source analysis, showing a visual modulation of the auditory-cortex response at N1 and P2 latency. However, CI users with bilateral hearing loss showed a distinct pattern of N1 topography, indicating a stronger visual impact on auditory speech processing compared to CI users with unilateral hearing loss and NH listeners. Furthermore, both CI user groups showed a delayed auditory-cortex activation and an additional recruitment of the visual cortex, and a better lip-reading ability compared to NH listeners. In sum, these results extend previous findings by showing distinct multisensory processes not only between NH listeners and CI users in general, but even between CI users with unilateral and bilateral hearing loss. However, the comparably enhanced lip-reading ability and visual-cortex activation in both CI user groups suggest that these visual improvements are evident regardless of the hearing status of the contralateral ear
The timecourse of multisensory speech processing in unilaterally stimulated cochlear implant users revealed by ERPs.
A cochlear implant (CI) is an auditory prosthesis which can partially restore the auditory function in patients with severe to profound hearing loss. However, this bionic device provides only limited auditory information, and CI patients may compensate for this limitation by means of a stronger interaction between the auditory and visual system. To better understand the electrophysiological correlates of audiovisual speech perception, the present study used electroencephalography (EEG) and a redundant target paradigm. Postlingually deafened CI users and normal-hearing (NH) listeners were compared in auditory, visual and audiovisual speech conditions. The behavioural results revealed multisensory integration for both groups, as indicated by shortened response times for the audiovisual as compared to the two unisensory conditions. The analysis of the N1 and P2 event-related potentials (ERPs), including topographic and source analyses, confirmed a multisensory effect for both groups and showed a cortical auditory response which was modulated by the simultaneous processing of the visual stimulus. Nevertheless, the CI users in particular revealed a distinct pattern of N1 topography, pointing to a strong visual impact on auditory speech processing. Apart from these condition effects, the results revealed ERP differences between CI users and NH listeners, not only in N1/P2 ERP topographies, but also in the cortical source configuration. When compared to the NH listeners, the CI users showed an additional activation in the visual cortex at N1 latency, which was positively correlated with CI experience, and a delayed auditory-cortex activation with a reversed, rightward functional lateralisation. In sum, our behavioural and ERP findings demonstrate a clear audiovisual benefit for both groups, and a CI-specific alteration in cortical activation at N1 latency when auditory and visual input is combined. These cortical alterations may reflect a compensatory strategy to overcome the limited CI input, which allows the CI users to improve the lip-reading skills and to approximate the behavioural performance of NH listeners in audiovisual speech conditions. Our results are clinically relevant, as they highlight the importance of assessing the CI outcome not only in auditory-only, but also in audiovisual speech conditions
Sociodemographic and clinical predictors of depression in children and adolescents: results of a two-year follow-up study
Depressive disorders are a main cause of disability-adjusted life years already in children and adolescents, in whom the clinical picture somewhat differs from adult-onset depression. Thus, we studied sociodemographic and clinical predictors of depression/dysthymia in a sample of minors. Our baseline sample (N=676) included patients at clinical high-risk for psychosis (CHR-P, n=183), inpatients admitted for non-psychotic, non-affective disorders (n=277), and community participants (n=216) of age 7.0 to 17.9 years (43.8% male). They were assessed by clinical psychologists for mental disorders and symptoms with various clinical interviews including the Mini International Neuropsychiatric Interview for Children and Adolescents, which was also used to assess depression/dysthymia in the CHR-P group at 1- and 2-year-follow up (n=117 and 73, respectively). Analyses followed a stepwise procedure at baseline with stepwise logistic regression analyses to identify the final baseline model that was tested in the follow-up samples. The final cross-sectional model included nationality and 13 clinical variables Mild depressive symptoms in particular played a decisive role here. Variables contributing significantly to the prediction varied over time, indicating that CAD depression/dysthymia may require different predictors depending on the follow-up time. Furthermore, the prospective accuracy of ruling out depression/dysthymia was superior to the accuracy of ruling it in. This lower positive likelihood ratio might be overcome in future by stepwise approaches that further stratify risk in those initially identified as at increased risk of depression/dysthymia
In vitro culturing of porcine tracheal mucosa as an ideal model for investigating the influence of drugs on human respiratory mucosa
It has been previously shown that fresh mucosa from different mammals could serve as raw material for in vitro culturing with the differentiation of cilia, which are the most important morphological structures for the function of the mucociliary system. Increasing legal restrictions on the removal of human tissue and changing surgical techniques have led to a lack of fresh human mucosa for culturing. Most of the animals that have been used as donors up to now are genetically not very close to human beings and must all be sacrificed for such studies. We, therefore, established a modified system of culturing mucosa cells from the trachea of pigs, which is available as a regular by-product after slaughtering. With respect to the possibility of developing “beating” cilia, it could be shown that the speed of cell proliferation until adhesion to the coated culture dishes, the formation of conjunctions of cell clusters and the proliferation of cilia were comparable for porcine and human mucosa. Moreover, it could be demonstrated that the porcine cilia beat frequency of 7.57 ± 1.39 Hz was comparable to the human mucosa cells beat frequency of 7.3 ± 1.4 Hz and that this beat frequency was absolutely constant over the investigation time of 360 min. In order to prove whether the reaction to different drugs is comparable between the porcine and human cilia, we initially tested benzalkonium chloride, which is known to be toxic for human cells, followed by naphazoline, which we found in previous studies on human mucosa to be non-toxic. The results clearly showed that the functional and morphological reactions of the porcine ciliated cells to these substances were similar to the reaction we found in the in vitro cultured human mucosa
Calculated parenteral initial therapy of bacterial infections: Antibiotic treatment in the elderly
This is the fifteenth chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience.Multimorbidity, an atypical symptomatology of infections in combination with multimedication, the associated interaction risks and serious consequences of synergistic side effects characterize the conditions when deciding on the use of antibiotics in old age. Strict decision regarding the indication itself, choice of the best antibiotic even considering rare side effects which may be dangerous in the elderly, determining the correct dose, dosing interval and the shortest possible duration according to the physiological status of the patient as well as monitoring effectiveness and toxicity detect expected and unexpected side effects early. Recommendations must reflect the peculiarities of antibiotic treatment in elderly patients.Dies ist das fünfzehnte Kapitel der von der Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) herausgegebenen S2k Leitlinie "Kalkulierte parenterale Initialtherapie bakterieller Erkrankungen bei Erwachsenen - Update 2018" in der 2. aktualisierten Fassung.Multimorbidität, eine atypische Symptomatik von Infektionen in Kombination mit Multimedikation, die damit verbundenen Interaktionsrisiken und die oft schwerwiegenden Folgen synergistischer Nebenwirkungen kennzeichnen die Bedingungen bei der Entscheidung über den Einsatz von Antibiotika im Alter. Strenge Indikationsentscheidung, Auswahl des besten Antibiotikums auch unter Berücksichtigung seltener, bei älteren Menschen gefährlicher Nebenwirkungen, Ermittlung der richtigen Dosis, des Dosierungsintervalls und der kürzestmöglichen Dauer entsprechend dem physiologischen Status des Patienten sowie Überwachung von Effektivität und Toxizität erkennen frühzeitig erwartete und unerwartete Nebenwirkungen. Empfehlungen müssen die Besonderheiten der Antibiotika-Behandlung bei älteren Patienten widerspiegeln
Calculated initial parenteral treatment of bacterial infections: Bacterial gastrointestinal infections
This is the fourteenth chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience.Bacterial gastrointestinal infections are still the leading cause of death worldwide. The chapter describes the etiology of bacterial gastrointestinal infections in Germany and their frequency. Recommendations are given for the calculated therapy of these infections and for targeted antibiotic therapy for known pathogens. Particular attention is paid to Clostridium difficile . The diagnostic and therapeutic options of antibiotic therapy of the various infection patterns in this pathogen are discussed.Dies ist das vierzehnte Kapitel der von der Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) herausgegebenen S2k Leitlinie "Kalkulierte parenterale Initialtherapie bakterieller Erkrankungen bei Erwachsenen - Update 2018" in der 2. aktualisierten Fassung.Bakterielle gastrointestinale Infektionen gehören weltweit immer noch zu den häufigsten Todesursachen. Im Kapitel werden die Ätiologie bakterieller gastrointestinaler Infektionen in Deutschland und ihre Häufigkeiten beschrieben. Es werden Empfehlungen zur kalkulierten Therapie dieser Infektionen und zur gezielten Antibiotika-Therapie bei bekanntem Erreger gegeben. Besonderes Augenmerk wird auf Clostridium difficile gerichtet. Die diagnostischen und therapeutischen Optionen der antibiotischen Therapie der verschiedenen Infektionsbilder bei diesem Erreger werden diskutiert
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