electric_brain, некто, выполняющий охранительно-обслуживающую функцию, проводник, знающий входы и выходы, знающий то место, куда открывает дверь, что-то в этом роде. У Эко и в других местах проскакивает этот термин по отношению к билиотекарям (людям, имеющим отношение к информации). Смотри здесь:

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Librarian work routines have been reengineered by eliminating their role as gatekeepers of the culture. According to Twitchell (1992), between 1850 and 1950 high culture was separated off from popular culture by the presence of a gatekeeper who determined what would be admitted into high culture. At least until 1950, and perhaps as late as the introduction of the paperback book and the conglomeration of the entertainment industry in the 1970s and 1980s, the selection of printed texts was viewed as the most important function of the gatekeeper, because print was viewed as the foundation of the culture. In Umberto Eco’s fable about a medieval monastery, librarians serve as the paradigmatic gatekeepers of the culture. Due to the influence of Melvil Dewey and the defining down of the profession, librarians in the United States always had an ambivalent relationship to their role as gatekeepers. But if librarians in the United States had been partly reduced to clerical intermediaries in the process of selecting printed texts, at least they were still positioned at the gate. In the era of the New Economy there was no gate to keep.

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