*2.3. Magnet Implants*

One other line of research worth mentioning here is the use of permanent magne<sup>t</sup> implants for sensory extension. The pads of the middle and ring fingers are the preferred sites for magne<sup>t</sup> implantation in the experiments that have been reported [18]. The mechanoreceptors in the fingertips are most sensitive to frequencies in the 200–300 Hz range. An interface containing a coil mounted on a wire frame and wrapped around each finger is used to generate magnetic fields to stimulate magne<sup>t</sup> movement within the finger. The output from an external sensor is used to control the current in the coil.

Experiments have been carried out in a number of application areas [18]. Ultrasonic range information, involves an ultrasonic sensor for navigation assistance. Distance information from the sensor is encoded as variations in the frequency of pulses. Effectively the closer an external object is to the sensor so the frequency of the pulses increased. The recipient has an accurate indication of how far objects are from the sensor. Further tests have used infrared sensors, which give an indication of the temperature of any objects remotely detected [19]. So the recipient 'feels' the temperature of remote objects.

### *2.4. Case 2 Conclusions*

The implants considered in this section certainly, in each case, allow the recipients abilities that are not normal for Homo sapiens. On top of that the recipients regard their implant as being part of their body, which is quite different to something that is merely worn. However, apart from the usual long term brain modification also apparent due to external conditions, there is no immediate change to the neural abilities of the individuals. Hence all those involved in this type of implant are considered to stay within the realms of Homo sapiens with regard to this specific experimentation. In other words, because their implant does not immediately alter their neural make up, the individuals are still considered to be a member of species Homo sapiens.
