Environmental dependent influences on the developmental refinement of excitatory inputs at an ultra-fast coincidence detector neuron

• Applicant: Professor Dr. Felix Felmy
• Subject Area: Cognitive, Systems and Behavioural Neurobiology ; Molecular Biology and Physiology of Neurons and Glial Cells
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 403373145

Binaural coincidence detection relies on the precise excitation-inhibition interaction in neurons of the medial superior olive (MSO). This precision is achieved through alterations during late postnatal development, a period marked by the establishment of prominent structure-function relationships in the auditory system. How excitatory inputs to MSO neurons refine during late postnatal development is unknown. In this proposal, we plan to mechanistically investigate these processes, through quantification of the developmental changes of excitatory currents and the morphology of axonal input patterns. To unravel what drives these changes we will perform these experiments in gerbils raised in omnidirectional white noise, which suppresses relevant sensory spatial cues. Conversely, the impact of sound-evoked activity will be eliminated using cochlear ablations. Applying both forms of sensory manipulation will allow us to distinguish whether sound evoked activity or the experience of spatial cues is crucial for functionally important circuit refinements in the MSO. Thus, our study will provide a quantitative insight into mechanisms that drive the development of synaptic excitation at an ultrafast coincidence detector neuron important for sound source localization.

• DFG Programme: Research Grants