The understanding, diagnosis and treatment of so-called ‘sensorineural’ hearing loss, caused by dysfunction of the cochlea in the inner ear, is severely lacking compared to other fields. There exist few techniques that are capable of pinpointing the reason for loss of hearing and virtually no treatments. Often all clinicians can do is confirm a diagnosis of impaired hearing. This deficiency in the understanding and treatment of deafness is already a major issue globally with five per cent of the global population having some kind of hearing loss. As populations begin to age thanks to other medical advances, this proportion will rise and the problem will become ever more urgent. A fundamental gap in our understanding of the physiological problems that can occur in the ear is our knowledge of the mechanisms of the sound signal transduction. This forms part of the scope of Hibino’s work; in particular, he is focused on analysis of the mechanisms behind the unique electrochemical properties of the cochlear endolymph. This is because the balance of potential and ions in the endolymph is fundamental to whether or not the inner hair cells depolarise and send a signal. The endolymph is highly positively charged, with transport of potassium ions (K+). It is suspected that potassium ion circulation is key to proper function, as those with hereditary deafness have mutations in the genes for potassium ion transporters and channels. In order to investigate this in more detail, Hibino and his team are employing microelectrodes capable of measuring both the electrical potential of the endolymph and the potassium ion concentration.