Current Projects

Current and planned Projects

Currently, we are working on the following projects:
(see also: Cooperations )

Neurophysiological basis of central tinnitus

Inner ear biology of glycine receptors

IZKF

)

Lesion-induced neuroplasticity and reorganization in auditory cortex

DFG

)

Effects of Ginkgo biloba extract on the development of central tinnitus

Schwabe Pharmaceuticals, Karlsruhe

)

Neurophysiological basis of central tinnitus

IZKF

)

Back to top

Brain form internal representations of their sensory surround. These are filtered models of the world restricted to the perception-relevant parts of the sensory inputs. Brains perform this task by sequential and parallel processing of the sensory information via synaptic transmission in neuronal networks. Consequently, malfunction of synaptic interplay leads to errors in the central sensory representations and thereby to erroneous percepts. One of such erroneous percepts is central tinnitus. It is characterized by over-representations of certain parts of the sensory input within the auditory cortex. These neuro-plastic changes of cortical representations make tinnitus a chronic disease and so far there exists little or no therapy to cure it. This project aim at the development of a therapy which is able to cure central tinnitus.

Inner ear biology of glycine receptors

IZKF

)

Back to top

Efferent innervation of the inner ear regulates auditory signal transduction by modulating auditory nerve and hair cell activity. The efferent cochlear feedback loop has been associated with improved detection of acoustic signals in background noise, selective auditory attention and protection of the inner ear against acoustic trauma. Glycine is the most important inhibitory transmitter in mammalian CNS besides GABA. However, due to technical difficulties in cochlear glycine receptor detection, no information about glycinergic neurotransmission in the peripheral auditory system has been available so far.
In our previous work, we gave the first description of glycine receptors in the rat cochlea, indicating a role of these inhibitory ion channel receptors in cochlear efferent innervation (Dlugaiczyk et al., 2008). Furthermore, our description of localization and developmental regulation of glycine receptors in the murine cochlea support our hypothesis of a glycinergic component in cochlear efferent signal transduction.
This project currently focusses on the description of the functional role of these cochlear glycine receptors.

Lesion-induced neuroplasticity and reorganization in auditory cortex

DFG

)

Back to top

Lesions of the human brain often lead to severe, non-treatable deficits of brain function. One reason for this is the largely missing regeneration of neuronal tissue, although non-lesioned brain regions may compensate for some of the deficits related to the lesion. Nevertheless certain functions may get completely lost, especially in cases where the function is more or less lateralized to one hemisphere, as it is the case e.g. for speech. Here we aim at a characterization of hemispheric differences in lesion-induced reorganization processes in the auditory cortex of an animal model.

Effects of Ginkgo biloba extract on the development of central tinnitus

Back to top

In this project we try to evaluate if Ginkgo biloba extract EGb 761Ž protects Mongolian gerbils from the development of a central tinnitus after noise trauma. For this we conduct behavioral and neurophysiological studies in animals treated with EGb 761Ž and placebo-treated controls. The study is supported by Schwabe Pharmaceuticals, Karlsruhe.

Finally, we are about to start projects on the following topics:

Effects of hearing aids on central auditory processing
Effects of hearing impairment on auditory discrimination learning