In vivo investigation of spontaneous activity in the prehearing mammalian auditory system

Sound is detected by extremely sensitive sensory cells, called hair cells, located in the inner ear. Hair cells transduce acoustic information (e.g. frequency and intensity) and convert them into electrical signals that are sent to the brain via auditory nerve fibres. This allows us to communicate and enjoy music.

Our current knowledge of how hair cells in the cochlea operate derive from ex vivo experiments, since in vivo measurements with subcellular resolution from the intact mammalian cochlea have long been considered unfeasible. This has created a substantial barrier towards our understanding of how the cochlea develop and function, since ex vivo work cannot replicate its sophisticated anatomy, innervation and physiology.

The aim of this PhD project is to understand the mechanisms that modulate and pattern the spontaneous firing activity in the developing mammalian cochlea in vivo, and how these influence central auditory refinement. This proposal will require the student to perform state-of-the-art techniques that are well established in the lab, including in vivo 2-photon functional imaging and in vivo AAV-gene delivery, applied to transgenic mice. These experimental approaches, combined with large data analysis (MATLAB and/or Python), will allow the student to investigate functional changes in the developing cochlea by monitoring the activity of individual cells and synapses.