Global brain

The global brain is a metaphor for the planetary ICT network that interconnects all humans and their technological artifacts. As this network stores ever more information, takes over ever more functions of coordination and communication from traditional organizations, and becomes increasingly intelligent, it increasingly plays the role of a brain for the planet Earth.

Proponents of the global brain hypothesis claim that the Internet increasingly ties its users together into a single information processing system that functions as part of the collective nervous system of the planet. The intelligence of this network is collective or distributed: it is not centralized or localized in any particular individual, organization or computer system. Therefore, no one can command or control it. Rather, it self-organizes or emerges from the dynamic networks of interactions between its components. This is a property typical of complex adaptive systems.

The World-wide web in particular resembles the organization of a brain with its webpages (playing a role similar to neurons) connected by hyperlinks (playing a role similar to synapses), together forming an associative network along which information propagates. This analogy becomes stronger with the rise of social media, such as Facebook, where links between personal pages represent relationships in a social network along which information propagates from person to person. Such propagation is similar to the spreading activation that neural networks in the brain use to process information in a parallel, distributed manner.

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