John Gartner, David Reiss and Steven Buser

Opinion contributors

On the face of it, President Trump doesn’t seem like a paragon of health. He’s 71, sedentary and borderline obese, with high cholesterol and a high fat diet. Despite this, through the blessing of “good genes,” says Rear Adm. Ronny Jackson, the White House doctor, Trump is in “excellent health” and would more than likely be healthy straight through a second term.

Jackson’s fulsome praise for Trump’s health, including his "cardiac health," generated widespread skepticism — and it was not limited to Trump’s physical condition. His account of Trump’s cognitive health was misleading as well, leaving the impression that all cognitive problems have been ruled out.

On one hand, we sincerely appreciate that Jackson gave the president a Montreal Cognitive Assessment test (MoCA), as we requested in a letter sent to him by 70 mental health professionals. We have now established the precedent that when enough concerns arise, presidential physicians can be expected to take a closer look at brain function.

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But it is important to be clear on what we now know and don’t know about the president’s mental fitness. Jackson portrayed the Montreal Cognitive Assessment as a grueling comprehensive battery. "We picked one of the ones that was a little bit more involved, it was longer. It was the more difficult one of all of them. It took significantly longer to complete, but the president did exceedingly well on it," he said.

In reality, this 10-minute screening test shows us the president can recognize a camel, read a string of letters, repeat three numbers backwards, and draw a clock. The MoCA is an excellent basic screen for dementia, but it comes with an error rate. In a study comparing its detection of cognitive impairments among stroke patients, the MoCA misses brain problems about one in five times.

A perfect score on the MoCA — Trump’s now famous “30/30” — effectively rules out actual full-blown dementia, which is a legitimate concern given his behaviors. But a perfect MoCA score is entirely compatible with significant cognitive decline relative to Trump himself. You can score 30/30 on these basic tests, but still be mentally declining — so-called pre-dementia. To rule out pre-dementia we would need a full neuro-psychological battery.

Trump asked to have the exam included because cognitive decline had become “the narrative for a while, and I think he saw doing the physical as an opportunity to put some of that to rest,” Jackson said.

But the president’s ability to recognize a camel doesn’t negate the troubling signs of cognitive decline that we and others have noted:

►Declining complexity of thought, rambling speech, difficulty completing a thought

►Markedly declining vocabulary over recent years, with over reliance on superlatives

►Episodes of slurred speech

►Failure to recognize old friends

►Perseveration of thought (perpetual repetition of the same concepts)

►Decreased fine motor coordination

►Difficulties reading, listening and comprehending

►Suspect judgment, planning, problem solving, and impulse control

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Particularly troubling is the notable decline from his own previously high level of functioning. In interviews Trump gave in the 1980s and 1990s, according to STAT’s Sharon Begley, “he spoke articulately, used sophisticated vocabulary, inserted dependent clauses into his sentences without losing his train of thought, and strung together sentences into a polished paragraph.” She called that a stark contrast to today when “Trump’s vocabulary is simpler. He repeats himself over and over, and lurches from one subject to an unrelated one.” For decades, Begley notes, research has shown such changes can be indicative of neurodegenerative disease.

Jackson has done a reasonable job ruling out gross brain dysfunction, but has still not ruled out a serious cognitive disease process that could be disabling for Trump’s current intensive job. And of course, we have not ruled out psychiatric illness because Jackson refuses to refer his patient for a psychiatric evaluation.

There is no reason to stop at a cursory screener that ruled out the most severe current organic pathology. A neuropsychologist would be able to compare Trump’s cognitive performance to peers of his age and educational level, and definitely determine whether he is experiencing pre-dementia. Such testing takes several hours, not several minutes, and provides a far more accurate result. The MoCA is but a fork in the road leading us on to other paths.

Unfortunately, Jackson and his patient both made clear they view the matter as closed.

John Gartner is a psychologist and former assistant professor at Johns Hopkins University Medical School. David Reiss of California has been a practicing psychiatrist for more than 30 years specializing in "front-line" adult and adolescent psychiatry. Steven Buser is a clinical psychiatrist practicing in Asheville, N.C. and a former U.S. Air Force psychiatrist.