Seite - 57 - in Cyborg Mind - What Brain–Computer and Mind–Cyberspace Interfaces Mean for Cyberneuroethics

Neuronal Interface Systems • 57 The importance of these procedures is significant when combined with careful staining systems. In this way, it is possible to place a stain in one zone of the brain and then, after a fixed amount of time, to kill the animal in order to study in which parts the dye has diffused. Adding different types of dyes under different circumstances to different parts of the brain enables neuro- scientists to build a massive three-dimensional map or catalogue of all the neuronal connections. By the time the data from thousands of mice is added (each one being killed in the process), it is possible to obtain a fascinating overview of life inside a mouse brain.39 Doing this for a human brain is theoretically possible, but there are some insurmountable obstacles: first, it requires a number of brains from deceased persons so that they can be cut into slices; second, it requires that appropriate dyes be added to specific parts of their brains just before these persons die; and, third, it requires massively scaled-up machines that provide a very large amount of data. The resolution of these systems is very good, but it is only possible to determine where neurological cells begin and end, without knowing very much about the final terminals, the intercell communication systems (the synapses). This lack of knowledge significantly restricts any understanding of what is really going on at each nerve ending. Electron Microscopy (EM) With electron microscopy (EM), which requires the brain to be dead, frozen, sliced and stained, it is possible to observe the very small junctions between the neurons. EM generates very good images of these complex junctions, pro- viding a detailed understanding of the structure of small volumes. However, it is not feasible to scale this up to the level of a mouse brain, let alone a human. Input Neuronal Interface Systems: Changing the Brain and Mind As already mentioned, scientists such as the Italian Luigi Rolando started to electrically stimulate parts of nonhuman animal brains back in the eigh- teenth century, while examining whether these were similar to those found in humans. This eventually resulted in clinical applications, with input neuronal interfaces providing stimulation to specific parts of the neuronal network in seeking to restore or improve function.40 These are technologies that take signals from the outside and provide it to an individual’s neuronal system. Again, they can be classified as invasive and noninvasive procedures. 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.