1. A method of optimizing an electrode tissue interface comprising: implanting at least one electrode in the vicinity of visual neural tissue; electrically stimulating the visual neural tissue through at least one electrode, wherein a stimulation signal to the at least one electrode comprises pulses at a first frequency within a frequency range of greater than 100 Hz and less than 10,000 Hz; measuring impedance of the electrode tissue interface to obtain a first impedance measurement; electrically stimulating the visual neural tissue through the at least one electrode, wherein a stimulation signal to the at least one electrode comprises subsequent pulses at a second frequency based on the first impedance measurement and within a range of greater than 100 Hz and less than 10,000 Hz; measuring impedance of the electrode tissue interface to obtain a second impedance measurement; and altering the location of said at least one electrode based on said first and second impedance measurements.