Limitations, possibilities and implications of Brain-Computer Interfaces

EEG Systems and Brain-Computer Interfaces (BCIs) are terms that are commonly used and discussed in the field of neurological research. From a technological point of view, the components and techniques used to build technical devices for this purpose are also widely discussed. Undifferentiated use of the terms EEG Systems and BCIs in the same context provokes a discussion because they in fact refer to distinct and different concepts and should be treated accordingly. This assertion shall be discussed and established without going into more technical detail of the concrete components. We will discuss the associated problem of the vague definition of BCIs and depict the essential limitations when using skull potential signals to realize such devices. To demonstrate alternative ways of realizing man-machine interfaces, we will describe the most recent research results, based on the example of a complex arm prosthesis. With respect to the requirements for realizing such a complex prosthesis we will show the possibilities and limitations of accessing the human brain structures and finally propose clear conclusions regarding the specifications for Brain-Computer Interfaces and the corresponding long term research and development goals.