'Trump's Lies vs. Your Brain'
"Unfortunately, it’s no contest. Here’s what psychology tells us about life under a leader totally indifferent to the truth."
"The sheer frequency, spontaneity and seeming irrelevance of his lies have no precedent. Nixon, Reagan and Clinton were protecting their reputations; Trump seems to lie for the pure joy of it. A whopping 70 percent of Trump’s statements that PolitiFact checked during the campaign were false, while only 4 percent were completely true, and 11 percent mostly true."
"Those who have followed Trump’s career say his lying isn’t just a tactic, but an ingrained habit. New York tabloid writers who covered Trump as a mogul on the rise in the 1980s and ’90s found him categorically different from the other self-promoting celebrities in just how often, and pointlessly, he would lie to them. In his own autobiography, Trump used the phrase 'truthful hyperbole,' a term coined by his ghostwriter referring to the flagrant truth-stretching that Trump employed, over and over, to help close sales. Trump apparently loved the wording, and went on to adopt it as his own."
"What does this mean for the country—and for the Americans on the receiving end of Trump’s constantly twisting version of reality? It’s both a cultural question and a psychological one. For decades, researchers have been wrestling with the nature of falsehood: How does it arise? How does it affect our brains? Can we choose to combat it? The answers aren’t encouraging for those who worry about the national impact of a reign of untruth over the next four, or eight, years. Lies are exhausting to fight, pernicious in their effects and, perhaps worst of all, almost impossible to correct if their content resonates strongly enough with people’s sense of themselves, which Trump’s clearly do."
https://www.politico.com/magazine/story/2017/01/donald-trump-lies-liar-effect-brain-214658
(This is an old article, but since Trump's lying is again being normalized, it's useful to understand the psychological consequences.)