Responding to queries on the subject, spokesman Hogan Gidley said simply: "No."
"He's sharp as a tack," Gidley told reporters on board Air Force One.
Trump, 71, will be examined at the Walter Reed military hospital in a Washington suburb Friday and the results are set to be made public.
During the 2016 presidential campaign, Trump published a letter by his long term doctor Harold Bornstein that stated he was in "excellent physical health."
Angered by the publication of a bombshell book that raised doubts over his mental faculties, Trump took to Twitter this weekend to describe himself as "a very stable genius" and "like, really smart."
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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