The term “cerebro-cigital interface” was defined as part of the terminology of the “Digital Era Framework”. Within this reference framework, four spheres are identified according to the type of information manifestation. The resulting scheme can be used to classify interfaces. The spheres are as follows: The infosphere, which consists of the analog infosphere and the digital infosphere, plus the cognisphere and the entisphere.
A “cerebro-digital interface” can be considered either as “bio-digital interface” or as “cogni-cigital interface”. If the brain is brought into focus in its capacity as a physical organ, then it is part of the biosphere and thus part of the entisphere. Functionally, however, it is part of the cognisphere.