  The emergence of opinion polarization within human communities -- the
phenomenon that individuals within a society tend to develop conflicting
attitudes related to the greatest diversity of topics -- has been a focus of
interest for decades, both from theoretical and modelling points of view.
Regarding modelling attempts, an entire scientific field -- opinion dynamics --
has emerged in order to study this and related phenomena. Within this
framework, agents' opinions are usually represented by a scalar value which
undergoes modification due to interaction with other agents. Under certain
conditions, these models are able to reproduce polarization -- a state
increasingly familiar to our everyday experience. In the present paper, an
alternative explanation is suggested along with its corresponding model. More
specifically, we demonstrate that by incorporating the following two well-known
human characteristics into the representation of agents: (1) in the human brain
beliefs are interconnected, and (2) people strive to maintain a coherent belief
system; polarization immediately occurs under exposure to news and information.
Furthermore, the model accounts for the proliferation of fake news, and shows
how opinion polarization is related to various cognitive biases.
