Fake news as such is an oxymoron. It is false information. It is surprising that it gets traction. Human brain likes novelty, unexpected and outlandish information or signals. It releases dopamine when such information is received. This chemical facilitates such messaging by transmitting it between nerve cells. Hippocampus and amygdala of the brain compare the novel information against existing memories. Such information is converted into long-term memory.

Thus fake news has a lot to do with memory formation. People are not able to distinguish between good and bad, and allow the popular to enter into the memory rather than what is correct. Brain suffers from cognitive bias. It does not filter outlandish material. It tries to relate the new information with what we have already experienced.

The brain confirms what is an opinion held. It is confirmation bias. At times even true news is branded fake since you believe that what views you hold are the only accurate views. It is naive realism.

It is necessary to verify or fact check the information. Communities can be trained to do this. We should hold independent opinions, and should not form our world view on the basis of what is expressed on social media. We should be careful about click-bait headlines. Social media statistics too are made up.