The ethics of brain interfacing using implantable electrodes

The ethics of brain interfacing using implantable electrodes The era of brain interfacing has arrived, whether one agrees or not, according to Philip Kennedy, CEO and Chief Scientist at Neural Speech Inc. He discusses two key ethical concerns: the longevity and stability of the signals, and brain stimulation. It is obvious that when a human brain is implanted for the purpose of prosthetic or cognitive enhancement, the implant should be permanent in the same way that joint replacements are permanent. The most used electrode is the Utah array. Earlier publications indicated that 85% of signals are lost within three years. (1) However, a recent paper suggests a better outcome. (2) It reviews long-term performance in 14 participants over 20 years. The average longevity is 2.8 years, with one participant showing neural activity at 7.6 years. The array has 96 tines and records from an average 35.6% of tines. The most recently implanted participants had better results. One, T5, survived 2780 days (7.625 years) and then became deceased, while another, T11, is still producing neural activity at 1728 days. The number of spikes, however, is less than 20 in one electrode and about 60 in another electrode. In addition, the number of spikes varies widely over time. The problem of spike non-stationarity is ongoing and partly compensated for by using population averages.