A look at the cognitive test that Trump aced and why it's 'not considered definitive'

Drawing a clock. Counting backward by sevens. Rattling off words that begin with "F" before a minute's up.

They may not sound like difficult tasks, but they're part of a cognitive exam that's getting a lot of attention because U.S. President Donald Trump aced it.

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For all their apparent simplicity, 10-minute quizzes like the Montreal Cognitive Assessment offer doctors a snapshot of someone's memory and certain other neurologic functions, one piece of information to help determine if trouble's brewing.

They're not a routine part of check-ups, either for a president or a not-so-famous senior.

Trump's doctor says he didn't see any symptoms that would prompt the test but that the president, who has faced questions about his mental acuity, requested it.

'It's not considered definitive'

So who really needs a cognitive assessment? They're usually offered only if there are concerns about memory or other cognitive functions concerns noticed either by the patient, a relative or the doctor.

"The value of screening without a complaint has not been established," cautioned Dr. David Knopman, a Mayo Clinic neurologist who chairs the Alzheimer's Association's medical and scientific advisory council.

And people should understand that "it's not considered definitive," he said."It's ultimately only a first pass at cognition."

The Montreal Cognitive Assessment MoCa for short is one of a list of similar tests that all aim to tap into specific functions.

MoCA was created by Lebanese-Canadian neurologist,Ziad Nasreddine.

"It's not a diagnostic test, but it's pretty sensitive in picking up subtle changes in cognition," things involving memory, attention and language but not mental health issues, said Dr. Ranit Mishori, professor of family medicine at Georgetown University.

Drawing a clock, and putting the right time on it, is a classic evaluation of how the brain comprehends spatial relationships. Someone with even very mild cognitive impairment is much more likely todraw a wobblyclock, or aim the hands wrong, than someone who's healthy.

Subtracting backward assesses things like attention and concentration.

Recalling a list of five words after five minutes of doing other tasks or coming up with at least 11 words that begin with "F" in a minute can assess short-term memory and language functions.

'Can't be evaluated with a snap of a finger'

Failing doesn't mean someone has dementia. There might be a fixable problem, like depression or medication side effects. Maybe the person isn't a good test-taker, or, for that counting task, never was very good at math.

And while passing is reassuring, someone who passes despite forgetting appointments or losing their way home probably still needs a closer look.

That's why doctors put together other information including questions about day-to-day functioning in order todeterminewho may need to take thenext step, a three- to four-hour battery of neuropsychological testing.

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"Cognitive concerns in middle-aged and elderly people need to be taken seriously. They can't be evaluated with a snap of a finger," Knopman said.

Getting that message out is an upside to all the publicity about Trump's test.

The downside: By reading these examples, you might have cheated. "If people practice it, guess what? It's invalid," Knopman noted.