A prominent clinical psychologist revealed that President Donald Trump's rambling tangents could indicate something disturbing ahead, according to a report on Thursday.Dr. John Gartner, former assistant professor at Johns Hopkins University Medical School, told The Daily Beast that Trump's "lengthy monologues about his construction projects" show that he has "growing signs of dementia and malignant narcissism—and it’s about to get worse."The evidence of his cognitive decline has been evident in the way Trump talks about his vanity projects, including the White House Ballroom or the Lincoln Memorial Reflecting Pool."Tangential speech is one of the diagnostic criteria for dementia," Gartner told the Beast.Trump will often move from one topic to another, circling back to the projects that involve his own name, Gartner explained."What he’s obsessed with is a function of malignant narcissism. He’s obsessed with things that reflect glory on him," Gartner said. "He’s changing Washington D.C. to Trump D.C."And although the White House might argue that Trump's health is not in decline, the reality shows otherwise, the doctor argued."It’s only going to go downhill from here," he said.