A prominent psychologist is warning that President Donald Trump’s increasingly erratic public behavior shows signs of severe cognitive deterioration layered on top of a long-standing personality disorder. Dr. John Gartner, a former Johns Hopkins professor and a clinical therapist with decades of experience, said on The Daily Beast Podcast that the 79-year-old president’s symptoms point to a dangerous and accelerating decline.

“When people develop dementia, they become the worst versions of themselves,” Gartner told host Joanna Coles. He described Trump’s recent verbal missteps, confusion, memory lapses, and impulsive outbursts as “clinical signs of dementia,” adding that those symptoms appear to be exacerbating what he believes is Trump’s preexisting “malignant narcissism.”

Gartner, who has repeatedly analyzed Trump’s cognition on the podcast, said the president’s concerns extend beyond personality traits. He pointed to specific physical indicators — including Trump’s “wide-based gait,” chronic venous insufficiency diagnosis, and a widely circulated September photo in which one side of Trump’s face appeared drooped — as potential signs of psychomotor decline.

“You do see he’s having difficulty raising his hand to salute,” Gartner said, referencing Trump’s appearance at a Veterans Day event. “And part of dementia and or stroke — because it really could be either or both — appears to be affecting the right side of his body. The face droop was on the right. The gait abnormality is on the right. These are signs.”

The psychologist’s comments come amid escalating public concern over Trump’s mental state. Since returning to office as the oldest president in U.S. history, Trump has faced a string of highly visible gaffes: confusing world leaders, mixing up countries, falling asleep during meetings, and abruptly losing his place in prepared remarks. Critics argue the behavior reflects cognitive decline; supporters say it is exaggerated by political opponents.

But the scrutiny intensified sharply this week after Trump verbally lashed out at a reporter aboard Air Force One who asked about the Jeffrey Epstein scandal. Trump snapped: “Quiet, piggy,” jabbing a finger at the journalist. The remark was met with global shock, prompting additional questions about his emotional stability and impulse control.

Gartner said the moment offers perhaps the clearest window yet into Trump’s deteriorating mental state. “He’s a malignant narcissist. Anything which doesn’t affirm his grandiosity and his omnipotence — which have gotten to almost psychotic degrees at this point — is a mortal threat,” he explained. “And the fact that he is perpetually being bombarded by waves of these threats… it is going to take a toll.”

He argued that Trump’s violent rhetoric — including calling for political enemies to be put to death for supposedly “seditious behavior” — is consistent with the disinhibition that often accompanies dementia. The inability to regulate emotion, he said, is typical of frontal-lobe deterioration.

Another recent episode Gartner pointed to: Trump abruptly canceled high-level trade negotiations with Canada because he disliked a viral clip featuring former President Ronald Reagan speaking against tariffs. “Who calls off a high-level meeting with the head of state because you got pissed off about something you saw on social media over your corn flakes?” he said. “That’s the kind of impulsivity we’re talking about.”

Gartner is not alone in sounding alarms. Only a week earlier, Trump’s niece Mary Trump — a psychologist herself — told the podcast she sees in her uncle the same behavioral patterns that marked the early stages of Alzheimer’s disease in his father, Fred Trump Sr.

“Well, of course, Alzheimer’s is genetic,” Gartner acknowledged. “He may have Alzheimer’s. He may have frontotemporal dementia. There’s more than one kind of dementia, but his symptoms seem to point more towards frontotemporal dementia.”

Frontotemporal dementia (FTD), often associated with impulsivity, emotional volatility, and loss of social filters, typically progresses faster than Alzheimer’s and can produce dramatic personality changes.

Gartner argues that these traits — grandiosity, rage, paranoia, and an increasingly distorted sense of reality — are not new for Trump, but they are becoming more severe. “Whatever personality issues people have before dementia, they become even more crude, disorganized, aggressive, confused versions of that personality disorder,” he said. “That is what we’re seeing.”

The White House did not respond to requests for comment.

As Trump prepares for another year of domestic crises, foreign-policy standoffs, collapsing approval ratings, and intensifying investigations into his historic ties to Epstein, experts warn that the pressure may accelerate the decline they believe is already underway.

For Gartner, the conclusion is stark: “We are witnessing a mind in crisis — and the country must face that reality.”