A5003210328- Neural dynamics and brain function
- Neuroscience and Neural Engineering
- Photoreceptor and optogenetics research
- Hearing, Cochlea, Tinnitus, Genetics
- Hearing Loss and Rehabilitation
- Plant and Biological Electrophysiology Studies
- EEG and Brain-Computer Interfaces
- Neuroscience and Music Perception
- Light effects on plants
- Animal Vocal Communication and Behavior
- Neuroscience and Neuropharmacology Research
- CNS Lymphoma Diagnosis and Treatment
- bioluminescence and chemiluminescence research
- Retinal Development and Disorders
- Advanced Electron Microscopy Techniques and Applications
- Pressure Ulcer Prevention and Management
- Functional Brain Connectivity Studies
- Categorization, perception, and language
- Vascular Tumors and Angiosarcomas
- Photosynthetic Processes and Mechanisms
- Wound Healing and Treatments
- Cardiac tumors and thrombi
- Advanced X-ray Imaging Techniques
- Cancer Immunotherapy and Biomarkers
- Single-cell and spatial transcriptomics
University of Göttingen
2014-2025
Universitätsmedizin Göttingen
2018-2025
Essen University Hospital
2023
Leibniz Institute for Neurobiology
2007-2022
German Primate Center
2015-2022
Johns Hopkins University
2022
Leibniz ScienceCampus Primate Cognition
2022
Johns Hopkins Medicine
2022
Otto-von-Guericke University Magdeburg
2020-2021
University of Bern
2020
Auditory prostheses can partially restore speech comprehension when hearing fails. Sound coding with current is based on electrical stimulation of auditory neurons and has limited frequency resolution due to broad spread within the cochlea. In contrast, optical be spatially confined, which may improve resolution. Here, we used animal models characterize optogenetic stimulation, genetically engineered express light-gated ion channel channelrhodopsin-2 (ChR2). Optogenetic spiral ganglion...
Primary sensory cortex integrates information from afferent feedforward thalamocortical projection systems and convergent intracortical microcircuits. Both input have been demonstrated to provide different aspects of information. Here we used high-density recordings laminar current source density (CSD) distributions in primary auditory Mongolian gerbils combination with pharmacological silencing cortical activity analysis the residual CSD, dissociate contribution spectral integration. We...
Virus-mediated expression of channelrhodopsin enables optogenetic stimulation auditory pathways and restoration auditory-driven behavior in deaf adult gerbils.
Abstract Cochlear implants (CIs) electrically stimulate spiral ganglion neurons (SGNs) and partially restore hearing to half a million CI users. However, wide current spread from intracochlear electrodes limits spatial selectivity (i.e. spectral resolution) of electrical CIs. Optogenetic stimulation might become an alternative, since light can be confined in space, promising artificial sound encoding with increased selectivity. Here we compare optogenetic, electric, acoustic by multi-channel...
When hearing fails, electrical cochlear implants (eCIs) provide the brain with auditory information. One important bottleneck of CIs is poor spectral selectivity that results from wide current spread each electrode contacts. Optical (oCIs) promise to make better use tonotopic order spiral ganglion neurons (SGNs) inside cochlea by spatially confined stimulation. Here, we established multichannel oCIs based on light-emitting diode (LED) arrays and used them for optical stimulation...
Article29 June 2020Open Access Transparent process μLED-based optical cochlear implants for spectrally selective activation of the auditory nerve Alexander Dieter orcid.org/0000-0002-9154-4833 Institute Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Germany Göttingen Graduate School Neurosciences Molecular Biosciences, Search more papers by this author Eric Klein orcid.org/0000-0003-2593-059X Department Microsystems Engineering (IMTEK), Freiburg, Daniel Keppeler...
Devising new and more efficient protocols to analyze the phenotypes of non-human primates, as well their complex nervous systems, is rapidly becoming paramount importance. This because with genome-editing techniques, recently adopted animal models for fundamental translational research have been established. One aspect in particular, namely cognitive hearing, has difficult assess compared visual cognition. To address this, we devised autonomous, standardized, unsupervised training testing...
Multi-scale X-ray phase contrast tomography (XPCT) enables three-dimensional (3D), non-destructive imaging of intact small animal cochlea and apical cochlear turns. Here we report on post-mortem excised non-human primate rodent cochleae at different [Formula: see text]-CT nano-CT synchrotron instruments. We explore sample embeddings, stainings regimes. Under optimized conditions preparation, instrumentation, protocol, retrieval, high image quality detail level can be achieved in 3D...
In this study, we describe differences between neural plasticity in auditory cortex (AC) of animals that developed subjective tinnitus (group T) after noise-induced hearing loss (NIHL) compared to those did not [group non-tinnitus (NT)]. To end, our analysis focuses on the input activity cortical neurons based temporal and spectral local field potential (LFP) recordings an in-depth brainstem responses (ABR) same animals. response NIHL NT find a significant general reduction overall power as...
Harmful environmental sounds are a prevailing source of chronic hearing impairments, including noise induced loss, hyperacusis, or tinnitus. How these symptoms related to pathophysiological damage the sensory receptor epithelia and its effects along auditory pathway, have been documented in numerous studies. An open question concerns temporal evolution maladaptive changes after their manifestation balance thalamocortical corticocortical input cortex (ACx). To address issues, we investigated...
Direct electrical stimulation of spiral ganglion neurons (SGNs) by cochlear implants (CIs) enables open speech comprehension in the majority implanted deaf subjects1-6. Nonetheless, sound coding with current CIs has poor frequency and intensity resolution due to broad spread from each electrode contact activating a large number SGNs along tonotopic axis cochlea7-9. Optical is proposed as an alternative that promises spatially more confined activation and, hence, higher coding. In recent...
The auditory thalamus is the central nexus of bottom-up connections from inferior colliculus and top-down cortical areas. While considerable efforts have been made to investigate feedforward processing sounds in (medial geniculate body, MGB) non-human primates, little known about role corticofugal feedback MGB awake primates. Therefore, we developed a small, repositionable cooling probe manipulate studied neural responses both cortex under conditions normal reduced temperature....
Direct electrical stimulation of spiral ganglion neurons (SGNs) by cochlear implants (CIs) enables open speech comprehension in the majority implanted deaf subjects1-6. Nonetheless, sound coding with current CIs has poor frequency and intensity resolution due to broad spread from each electrode contact activating a large number SGNs along tonotopic axis cochlea7-9. Optical is proposed as an alternative that promises spatially more confined activation and, hence, higher coding. In recent...
Corticofugal projections outnumber subcortical input by far. However, the specific role for signal processing of corticofugal feedback is still less well understood in comparisonto feedforward projection. Here, we lesioned corticothalamic (CT) neurons layers V and/or VI auditory cortex Mongolian gerbils laser-induced photolysis to investigate their contribution cortical activation patterns. We have used laminar current-source density (CSD) recordings tone-evoked responses and could show...
Auditory signals that contain coherent level fluctuations of a masker in different frequency regions enhance the detectability an embedded sinusoidal target signal, effect commonly known as comodulation masking release (CMR). Neural correlates have been proposed at stages auditory system. While later seem to suppress response masker, earlier are more likely their signal when is comodulated. Using flanking band paradigm, present study investigates how CMR represented inferior colliculus...
Functional hemispheric lateralization is a basic principle of brain organization. In the auditory domain, right cortex (AC) determines pitch direction continuous stimuli whereas left AC discriminates gaps in these stimuli. The involved functional interactions between two sides, mediated by commissural connections, are poorly understood. Here, we selectively disrupted interhemispheric cross talk from to primary and vice versa using chromophore-targeted laser-induced apoptosis respective...
In recent years, the utility and efficiency of automated procedures for cognitive assessment in psychology neuroscience have been demonstrated non-human primates (NHP). This approach mimics conventional shaping principles breaking down a final desired behavior into smaller components that can be trained staircase manner. When combined with home-cage-based approaches, this could lead to reduction human workload, enhancement data quality, improvement animal welfare. However, our knowledge,...
Cochlear implants (CIs) restore activity in the deafened auditory system via electrical stimulation of nerve. As spread electric current biological tissues is rather broad, spectral information provided by CIs limited. Optogenetic nerve has been suggested for artificial sound coding with improved selectivity, as light can be conveniently confined space. Yet, foundations optogenetic strategies remain to established. Here, we parametrized stimulus-response-relationships pathway gerbils...
Abstract Optogenetic control of cells is a key life sciences method and promises novel therapies. Here we report on ChReef, an improved variant the channelrhodopsin ChRmine. ChReef offers minimal photocurrent desensitization, unitary conductance 80 fS closing kinetics 30 ms, which together enable reliable optogenetic at low light levels (nano-Joule) with good temporal fidelity allows sustained stimulation. We demonstrate efficient red-light pacing depolarization block ChReef-expressing...
1920 stellte Braun erstmals eine neue Hauttransplantationstechnik zur Behandlung von Wunden vor, in denen konventionelle Hauttransplantationen aufgrund Scherkräften, hohem Druck und exzessiver Wundsekretion nur selten erfolgreich durchgeführt werden können. Wir präsentieren klinische Anwendungsbeispiele Ergebnisse aus den vergangenen 10 Jahren, wir diese Technik bei Wundheilungsstörungen unterschiedlichster Genese eingesetzt haben. In Kombination mit der modernen Vakuumtherapie kann die...