There has been an increasing trend towards hearing preservation surgery for patients undergoing cochlear implantation. Literature supports improved speech and pitch perception in quiet and noise for subjects who combine the use of their implant with any residual preserved natural hearing compared with using the implant alone. Once again the the underlying mechanisms for this are unknown. It would be of scientific interest to investigate the interaction between natural residual hearing and hearing via a cochlear implant. It is likely that this cohort of subjects process speech similarly to those with normal hearing.