President Donald Trump’s recent confusion with words and facts, including about his own father, could be signs of pre-dementia and deteriorating cognitive skills, some mental health experts warn.

“The ‘Tim Apple’ episode a few weeks ago, his calling Venezuela a company, and then yesterday, confusing his grandfather’s birthplace with his father’s, mispronouncing ‘oranges’ for ‘origins,’ and stating out of the blue, ‘I’m very normal,’” recited Bandy Lee, a professor of psychiatry at Yale University who has been waving red flags about Trump’s mental state for years. “There is no question he needs an examination.”

“I think he’s suffering from pre-dementia. And it’s only getting worse,” said John Gartner, a clinical psychologist with practices in New York City and Baltimore.

Both acknowledged that they have not given Trump a full examination and could not offer a definitive diagnosis, but Gartner noted that the president’s behaviors are on full view every single day. “The evidence is right in front of our eyes,” he said.

Lee and Gartner are among the relatively few mental health professionals speaking out about Trump’s condition because of guidelines against speculating about patients a doctor has not personally examined. Both said those standards should not apply in situations where the safety of the nation is at stake and the president’s behavior is on public display.

White House spokesman Hogan Gidley denied that Trump had any cognitive difficulties and said that those who actually work with Trump “see his total command of complex issues” on a daily basis. “These ‘doctors’ are disgusting, and they should be ashamed of themselves for trying to use their titles to push their own personal political views.”

Speaking in the Oval Office Tuesday, Trump said that his father was “born in a very wonderful place in Germany.” In fact, his father was born in the Bronx. It was his paternal grandfather who emigrated from Germany. The president also said repeatedly that he wanted to take a look at the “oranges” of the special counsel investigation against him, when he clearly meant “origins.”

Last month, Trump called Apple CEO Tim Cook “Tim Apple” ― but later claimed that he had, in fact, said “Tim Cook Apple,” but people missed “Cook” because he’d said it very rapidly, and finally claimed that he was trying to save time by skipping some words.

“That was real cognitive slippage,” Gartner said. “And then he tried to cover for it.”

The White House this year did not make available the doctor who performed Trump’s annual physical exam and released scant information about its results.

In contrast, last year Trump authorized physician Ronny Jackson to field questions about his health for nearly a full hour. The president himself bragged about his performance on the Montreal Cognitive Assessment, a screening tool for Alzheimer’s disease that asks the patient, for instance, to identify a camel and to draw a clock.

“There aren’t a lot of people that can do that,” Trump said days later, boasting of his 30-out-of-30 score to a Republican National Committee audience.

That test, though, was never designed to be an in-depth analysis of cognitive function, Lee and other experts said. “Ronny Jackson declared his boss and commander-in-chief ‘fit for duty’ based on a 10-minute cognitive screen on which full-blown Alzheimer patients and hospitalized schizophrenia patients are known to score in the normal range,” she said.

Lee edited a book of essays by mental health professionals warning Trump’s mental state is dangerous, and in 2017 met with Congress members who were exploring forming an expert panel to look into the issue.

Large numbers of Americans who are not mental health professionals have also started to question Trump’s mental condition, including prominent critics like George Conway, the husband of top White House aide Kellyanne Conway. They’ve noted both the president’s actions and his televised speeches and public remarks, in which he is frequently incoherent and goes off on long, unrelated tangents.

On Tuesday night, during his speech at the National Republican Congressional Committee spring dinner, Trump, who was then in the middle of 90 minutes of rambling remarks, veered off on a two-minute, 22-second detour that touched on how wind turbines kill bald eagles and other birds, moved on to how North Korean dictator Kim Jong Un was not ready for a deal, came back to how people who use wind power can’t watch television if the wind doesn’t blow, and finished with former President Barack Obama playing golf in Hawaii:

Hillary wanted to put up wind. Wind. If you ― if you have a windmill anywhere near your house, congratulations: Your house just went down 75 percent in value. And they say the noise causes cancer. You tell me that one, OK? “Rrrrr, rrrrr” ― you know the thing that makes the ― it’s so noisy. And of course it’s like a graveyard for birds. If you love birds, you’d never want to walk under a windmill because it’s a very sad, sad sight. It’s like a cemetery. We put a little, we put a little statute for the poor birds. It’s true. You know in California, if you shoot a bald eagle, they put you in jail for five years. And yet the windmills wipe ’em all out. It’s true. They wipe ’em out. It’s terrible. And I told the other day at CPAC. Great people at CPAC. We had an incredible thing. I had nothing to do. It was early on a Saturday morning. I had just gotten back from dealing with Kim Jong Un. We had a walk. He wasn’t ready for a deal but that’s OK because we get along great. He wasn’t ready. I told him, you’re not ready for a deal. That’s the first time anybody has ever told him that and left. It never happened to him before. Nobody’s ever left. But I said you’re not ready for a deal, but we’ll make a deal. We have a good relationship. We have a good relationship. But I told a story about, at CPAC. The woman, she wants to watch television. And she says to her husband, “Is the wind blowing? I’d love to watch a show tonight, darling. The wind hasn’t blown for three days. I can’t watch television, darling. Darling, please tell the wind to blow.” No, wind’s not so good. And you know, you have no idea how expensive it is to make those things. They’re all made in China and Germany, but the way, just in case you’re ― we don’t make ’em here, essentially. We don’t make ’em here. And by the way, the carbon, and all those things flying up in the air, you know the carbon footprint? President Obama used to talk about the carbon footprint, and then he’d hop on Air Force One, a big 747 with very old engines, and he’d fly to Hawaii to play a round of golf. You tell me, the carbon footprint.

“He has been growing less and less coherent,” Lee said, pointing to Trump’s appearance a month ago at the Conservative Political Action Conference, which Trump referenced on Tuesday night. “His two-hour CPAC speech revealed a lot of rambling sentences, tangential thought trails, word-finding difficulties and repetition.”

On Twitter last month, George Conway wrote: “*All* Americans should be thinking seriously *now* about Trump’s mental condition and psychological state, including and especially the media, Congress ― and the vice president and Cabinet.”

That exhortation followed up on a string of Conway tweets listing the symptoms of narcissistic personality disorder from the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.

Gartner, though, said Trump’s condition appears to be an even worse variant of that disorder and a condition that is common to dictators: malignant narcissism, whose traits include narcissism, paranoia, sociopathy ― exhibited by constant lying ― and sadism.

“He has been getting worse in the last few months,” Gartner said, adding that he agrees with Conway that earlier interviews show how far Trump’s decline has progressed. In the past, Gartner said, “he not only spoke in complete sentences, he spoke in complete paragraphs.”

Gartner pointed out that one of the symptoms of narcissism is repeated lying. “Donald Trump is the most documented liar in human history,” he said. “We observe his behavior every day.”

This story has been updated with comment from White House spokesman Hogan Gidley.