Abstract
This study has shown that an electrode array can be passed along the whole length of the cochlea if it is inserted through an opening in the scala tympani of the apical turn. The electrode must have the appropriate mechanical properties and some of these were stiffness and extensibility. This electrode and operative approach should be helpful in stimulating the terminal auditory nerve fibres on a place basis, which is desirable if patients with severe sensorineural deafness are to be helped with a cochlear implant.