a talented graduate student completed his or her Ph.D. their expertise was lost and a new start with a new researcher had to be made (interview with B. Simmons, Stanford University, April 20, 1992).

When British observers John Ballantyne, Edward Evans, and Andrew Morrison visited Standford in October 1977, only two (volunteer) patients had been implanted (in September), with a newly developed 4-electrode device; the objective was to "optimize stimulation strategies," although it was intended that the subjects "be provided with wearable control units in the future" (Ballantyne et al., 1978). At the time of this visit, Blair Simmons continued to regard cochlear implantation as an experimental procedure, and took the view that widespread clinical prescription of single-channel devices was premature. "All implants have been multichannel, made directly into the body of the cochlear nerve through the modiolus, in the belief that, with direct contact between electrodes and nerve fibers, thresholds would be lower, excitation would be more discrete and there would be less chance in principle of electrodes encountering 'gaps' in the array of surviving fibers than in the cochlea" (Ballantyne et al., 1978). Development work was continuing on a number of fronts. One priority was replacement of the transcutaneous button transmission system by a much more sophisticated system then undergoing tests. The British visitors were impressed by the electronic link system being developed. "This employs two separate transmission systems: an ultrasonic link transmitting pulse-coded information on when each of the four channels is active, their pulse duration, phase and amplitude; and a radio frequency link providing the power for the implanted package'' (Ballantyne et al., 1978). Various aspects of the "take home" package with which patients should be supplied were still under discussion. On the basis of results from the first two patients plus one awaiting implantation it was hoped to develop "a coding system which will establish transfer of information on, say, the amplitude envelope of the acoustic signals and on the speech fundamental (laryngeal) frequencies. There is still discussion within the team about the optimal strategy which should be employed both for the psychophysical testing and for the short-and long-term attempts at coding speech signals" (Ballantyne et al., 1978).

The intention was still to keep the program small, to try to get the optimum information from small numbers of experimental subjects ("healthy English-speaking adults between 21 and 65 years of age, with total post-lingual deafness … adequately motivated and still functioning in society") (Ballantyne et al., 1978).

By this time Dr. Robin Michelson, an ear surgeon at the University of California, San Francisco (UCSF), who had previously worked at Stanford, had also started work. Michelson was a man of unusual background, having been trained originally as a physicist. He had also done some cat studies (which had led him to a number of theoretical conclusions that informed his subsequent clinical



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