A leading psychologist has issued a stark warning about Donald Trump’s mental state, suggesting that the former president’s increasingly erratic behavior is a sign of dementia amplifying an underlying personality disorder.
Dr. John Gartner, a prominent psychologist, former Johns Hopkins University professor, and author, recently appeared on The Daily Beast Podcast where he argued that Trump is displaying clear clinical signs of cognitive decline.
According to Gartner, when someone with a pre-existing personality disorder—specifically what he describes as “malignant narcissism”—develops dementia, their worst traits become exaggerated.
“People with dementia don’t just get confused,” Gartner explained. “They become the most extreme, unfiltered version of who they already were—more impulsive, more aggressive, more disorganized.”
He pointed to Trump’s frequent verbal stumbles, memory lapses, and moments of apparent confusion as textbook indicators of progressing dementia.
Gartner also highlighted physical signs of possible “psychomotor retardation,” including an incident on Veterans Day when Trump appeared to struggle to raise his right arm fully to salute.
“You can see the difficulty lifting his hand,” Gartner noted. “There’s also the noticeable droop on the right side of his face in some recent appearances, and the wide-based gait where he swings his right leg outward in a semicircle.
Those kinds of asymmetrical motor issues can be associated with dementia, small strokes, or both.”
The concerns come amid ongoing questions about Trump’s health, particularly after his unscheduled visit to Walter Reed Medical Center in October for what the White House described as “advanced imaging and preventive assessments,” including an MRI.
Trump later described the results as flawless, saying the doctors told him they were “some of the best reports they’ve ever seen for a man his age.”
However, several medical professionals have expressed skepticism about the lack of detailed disclosure regarding the visit, with some speculating that key information may have been withheld.
Gartner’s assessment adds to a growing chorus of mental health experts—many of whom have never personally examined Trump but are commenting based on public behavior—who argue that the 79-year-old’s cognitive and behavioral changes raise serious questions about his fitness for high-stakes leadership.
