TORONTO -- U.S. president-elect Joe Biden has spoken frequently about the immense challenge of dealing with a stutter in his frequent speeches as a member of the U.S. Senate, as vice-president, and even more as the soon-to-be 46th president of the United States.

While his verbal stumbles on the campaign trail caused some to question his mental fitness, Eric S. Jackson, assistant professor of communicative sciences and disorders at New York University, says people may be more understanding if they understood the difficulty of living with a stutter.

Jackson, who is also a speech therapist, told CTV's Your Morning on Wednesday that people who stutter often deal with people assuming they are slow, less intelligent or anxious.

"In the most general sense, stuttering is a person knowing what they want to say, but in that moment, their body breaking down and them not being able to say, and this is due to a combination of genetic, neurological, and environmental factors," Jackson said in an interview from New York.

"But the important thing to know about stuttering is that you can't always see it," he added.

Jackson, who also has a stutter, explained that those who stutter are often made fun of, not just as kids, but also as adults.

For example, U.S. President Donald Trump frequently mocked Biden's stutter at campaign rallies, alleging his Democratic rival was pretending to endear himself to the American public.

"People who stutter learn very early on that there's a stigma associated with stuttering, that stuttering is bad and it's something that you're not supposed to do. So there's a lot of shame around stuttering. For lots of people, the experience of stuttering comes [with] trying to hide or conceal stuttering," Jackson said.

Jackson says he believes that Biden’s eye movements, such as blinking and glancing downwards, are part of his ongoing efforts to manage his stutter. Jackson said these are called accessory or compensatory behaviours.

"For some reason, moving other parts of our bodies sometimes helps or sometimes seems to jolt us out of a moment of stuttering. We're not really sure why this happens, but these behaviours can become very ingrained in how a person stutters, and they really only complicate the stuttering problem," he explained.

Jackson said speech therapists wouldn't typically introduce accessory behaviours as strategies in therapy and often work with people in trying to reduce these sorts of mannerisms.

Jackson noted that Biden also appears to intentionally not stutter by switching to an alternative word in a technique called "circumlocution."

This happened during a town hall in August 2020 when Biden briefly got stuck trying to say "Obama," before quickly subbing in "my boss."

Biden previously told CNN that he didn't receive professional help for his stutter, but instead practised in the mirror for hours, reciting poetry written by Irish poets including William Butler Yeats.

Moving into a career in politics, Biden said he started marking up his speeches, using slashes to show where he could take a moment to pause, noting that the method forces him not to rush. The same method is depicted in the Academy Award-winning movie "The King's Speech" about England's King George VI’s stutter.

Jackson says this method helps a person learn how to phases portions of a speech in separate "chunks."

"The benefit of this type of strategy is that it reduces the overall rate of speech, which does seem to help a person move through stuttering in an easier way," he said.

However, Jackson said it is important to point out that using these speaking strategies can be "extremely challenging."

"The person who stutters needs to think about what they're saying, while at the same time thinking about how they're going to use their speech system or their body to talk," Jackson said.

"As a speech therapist, I love working with people on speaking strategies and therapy, but there should be no expectation that all people who stutter should be using speaking strategies," he added.

Growing up, Jackson said he was "petrified" about the possibility of having a job that would require him to talk a lot. Now, he says seeing a U.S. president who stutters is a "golden opportunity" for others who struggle with their speech to see that they can still have high-profile careers.

"The fact that he stutters sends a message that that you can stutter and still have an important job and for kids… I can only think that seeing Joe Biden stutter -- that seeing the president of the U.S. stutter -- would at least lessen the burden and lessen those fears a little bit for lots of kids out there who stutter," Jackson said.

He added that the public discourse about stuttering has "already increased tremendously" following Biden’s election campaign, and will only expand as he takes on the presidency.

"I think we have an opportunity to spread awareness about stuttering and increase understanding about what stuttering really is," Jackson said. "This is going to normalize stuttering so that it's more OK to talk about it."