Upcoming Biden vs Trump presidential debate to be "an incredible test of their cognitive competence": Expert

US President Joe Biden and former President Donald Trump are poised for a historic confrontation next week, in what will be the earliest presidential debate in modern U.S. history.

Biden, 81, and Trump, 78, are running neck-and-neck in national polls, with a significant portion of the electorate still undecided as the November 5 election approaches.

This debate, therefore, is set to be a pivotal moment for both contenders. It will offer a vivid comparison between the two oldest candidates ever vying for the U.S. presidency, amid growing voter concerns about their age and cognitive abilities, Reuters reports.

“It's an incredible test of their cognitive competence. This is our chance to see how much they've declined or if they've declined,” said Patrick Stewart, a political science professor at the University of Arkansas and an author of a book on presidential debates.

Over half of Americans believe both are too advanced in age for another term, according to an April ABC News/Ipsos poll. However, there are consistently more doubts regarding Biden’s capabilities, CNN reports.

The 90-minute CNN debate will enforce strict rules: limited speaking time, a prohibition on notes, and no audience presence. Both candidates must brace for rigorous questioning and a format that challenges their usual strategies, Stewart noted.

As far as debate strategies are concerned, Biden plans to portray himself as a wise and stable leader, contrasting Trump’s divisive and chaotic nature. His team aims to emphasise Trump’s extreme stances on issues like abortion, his threats to democracy, and his dependence on wealthy donors, according to a campaign insider.

On the other hand, Trump's team suggests he will be adopting a more relaxed approach to his debate preparation compared to previous years. Trump’s camp intends to hold Biden accountable for his administration’s handling of immigration and inflation, as well as his response to global crises like the Israel-Hamas conflict and Russia’s invasion of Ukraine, according to senior campaign adviser Brian Hughes.

With both camps under pressure to demonstrate their candidate's preparedness to lead the nation amidst ongoing domestic and global challenges, this unprecedented early face-off could have far-reaching implications for the US elections outcome.