That person was Ziad Nasreddine - who designed the test.
Senator Lindsey Graham said Trump was on board early last week with a tentative "compassionate" deal between Democrats and Republicans to guarantee the status of almost 700,000 "Dreamers" - people who came to the United States illegally as children and are now threatened with expulsion.
The doctor said he was getting a nutrition specialist to meet with the White House chefs, "to make sure we're cutting the calories and the fats and the carbohydrates as much as we possibly can while making good meals for him".
I'd like to repeat that, the world's top diplomat gave an entire press conference to answer questions on whether or not he used the word, "moron" in reference to Trump.
The White House doctor announced during a briefing with reporters that he selected the Montreal cognitive test among several available.
The exam was conducted by Rear Adm. Ronny Jackson, who was appointed by Barack Obama back in 2013.
"I think somebody on his staff gave him really bad advice from 10:00 to 12:00 on Thursday", Graham said.
Washington had been abuzz in recent days with details from a tell-all-style book suggesting everyone in Trump's entourage questions his mental stability.
Michael Wolff's Fire and Fury Is Heading to Television
Public libraries around the country have been inundated with demands for the highly contentious book Fire and Fury . However, top White House aides also admitted Wolff, including senior counselor Kellyanne Conway.
Adding to some online observers' skepticism that Trump's measurements were accurate was the fact that 239 pounds, at 6-3, conveniently put his body mass index at 29.9 - just below the 30.0 threshold for him to be officially described as obese, rather than merely overweight.
Nasreddine cautioned that his exam doesn't test for everything.
It's created to identify early cognitive decline - not other psychological issues, or personality attributes, such as judgment. He also points out that it can be tricked by someone with a very high level of education. "It has limitations", he said.
The president performed "exceedingly well" on cognitive screening, which is not standard but was requested by Trump. "It does not absolutely assess personality issues". Lindsey Graham, R-S.C., was at the infamous meeting with Trump and told others about his racist language.
The irony of the Trump administration pointing to a test devised by an immigrant was not lost on Nasreddine, whose family came to Canada during Lebanon's civil war. Patrick Leahy, D-Vt., asked her specifically if she heard the vulgarity used or a "substantially similar word" to describe certain countries.
He says he hopes the president draws some lessons from his story. "I mean, I'm strong, physically", he said.
Mr Trump campaigned for president in 2016 promising a hard line on immigration, including deporting all of the roughly 11 million illegal immigrants already in the country and a "total and complete shutdown" of the entry of Muslims into the United States.
"I actually do not know that, sir", Nielsen replied. "I think he's one of those people who just does not need a lot of sleep".