Page - 86 - in Cyborg Mind - What Brain–Computer and Mind–Cyberspace Interfaces Mean for Cyberneuroethics

86 • Cyborg Mind available in the future and whether all the information about the optimum location for implanting the device has been provided to the prospective patient.189 Any activity in the brain will also cause other brain cells to migrate towards, and cluster around, the device. Indeed, some of these cells will recognise the implant as being foreign to the body and will then work hard to destroy or evict it. Furthermore, if an electrode is implanted, this clustering will most probably eventually interfere with its ability to pick up or give signals.190 But much progress has been made in recent decades into developing materials that resist rejection. For instance, nanoscale coatings on surgical implants may give enhanced biocompatibility. However, it is still necessary to assess the risk of abrasion in long-term use and the possible release of nano-particles into the brain. Connecting the device with the outside world also creates challenges. Implanting any item into brain tissue will cause local neuronal and vascular damage and will introduce an increased risk of infection.191 The first devices all relied on wires reaching from the electrodes through the skin, but the exit site for these wires could give rise to possible infections, with the wires form- ing a surface along which bacteria can travel. Moreover, the wires themselves can easily act as aerials, picking up radio signals or electrical interference from the surrounding environment. If this occurs, the device may malfunction or the information it is transmitting may be lost in the midst of the ‘noise’.192 However, future wireless appliances may be able to partially address some of these challenges. In normal situations, a person often has a number of different ways to help him or her communicate, such as talking, waving a hand or in more extreme situations blinking. If a person believes that others have misunderstood what he or she wanted, he or she can reinforce or correct the message by doing something. But in some situations where neuronal interfaces are used, such as when a person is locked-in, communication through the device may be the only means of conveying a message. If that information is disrupted through interference, then the person has no secondary means of correcting the situation.193 Thus, a system linking a brain to a wheelchair would need to seriously consider a secondary safety system in order to prevent dangerous or unintended movements. Biological risks relating to neuronal interfaces should also address the long- term consequences that may not be envisaged at the beginning. For example, it may eventually be necessary to remove a device because it became defec- tive, less effective or worn out. This means that in the case of implants, revers- ibility and controllability are significant factors. If something goes wrong, it is important to consider whether the device could be taken out of a person, replaced with a new or more improved system, or even just deactivated. This open access edition has been made available under a CC-BY-NC-ND 4.0 license thanks to the support of Knowledge Unlatched. Not for resale.