President Donald Trump experienced full-body twitching during a Friday speech at NASA's Johnson Space Center in Texas — an episode that one forensic psychologist argued was consistent with what is known as a focal aware seizure, or partial seizure.

John Paul Garrison, a Georgia-based clinical and forensic psychologist, analyzed footage of the speech in a video published Saturday, calling it "the most concerning footage" of the president he has analyzed to date. His assessment joins a broader pattern of public scrutiny of Trump's health as he serves a second term as the oldest person elected to the U.S. presidency, though assessments made from video footage alone, without examination or medical records, cannot constitute a diagnosis — a limitation Garrison himself acknowledged in framing his remarks as his own opinion.

"For the past few months, I have been showing various neurological concerns and some steep signs of decline from President Trump, but what we're going to start with today is extremely concerning," Garrison said.

The footage was captured during Trump's remarks at a Congressional Space Medal of Honor presentation in Houston, Texas. As Trump spoke — at one point boasting about the stock market's performance — he briefly paused mid-sentence while his body twitched.

"What you just observed was a distinct and concerning neurological event, and you got to watch it cross both hemispheres in his brain — I'll explain what I mean," Garrison said, noting that his analysis was strictly his own opinion.

"You saw his right arm jerk, and then you saw him blink, you heard his voice hesitate, and then you saw his left arm jerk. You literally watched it travel across his brain. To be very clear, these were not simple muscle spasms; this is not something related to pain — you don't see any pain on his face. You actually watch it travel from one arm, to his eyes, to his voice, to his left arm."

Garrison went on to suggest that Trump may have suffered a focal aware seizure, an epileptic event that tends to be less severe than generalized seizures and is usually brief. Such seizures, in which a person remains aware, can also stem from causes other than epilepsy, including prior stroke or other brain injury — which is the specific connection Garrison raised.

"Now, what this is very consistent with is something that we see in people that have had strokes called a focal aware seizure or a focal motor seizure, and this can be focused in one part in the brain, and occasionally, it can spread to both parts of the brain," said Garrison, who is profiled at Psychology Today.

"I'm not insisting that's what's going on with him, but it is clearly something neurological, whether it's post-stroke or something else." No medical evaluation, physician statement, or diagnosis regarding the episode has been made public, and involuntary movements can have a range of medical explanations beyond those Garrison discussed.