Facial expressions spoke volumes when mics were muted in the presidential debate

This story first appeared in NPR's live blog of the presidential debate between Kamala Harris and Donald Trump. See how the night unfolded.

In a presidential debate, the split screen shot of the candidates — with one candidate speaking and the other reacting non-verbally — can easily become the story of the debate.

In Tuesday night's presidential debate, while former President Donald Trump delivered voluble answers often looking and sounding angry, Vice President Harris’ face was doing a lot of work.

At times her expression was pained, at other moments she leaned her head back and took a breath looking to the sky in a motion that was just one step shy of an eye roll. And at other times, she got a look that said "bless your heart" without actually saying it.

As NPR’s Deepa Shivaram wrote, for Harris, facial expressions have been an important part of her past debate performances. And that was (very noticeably) the case on Tuesday night too.

"She understood the split screen," CBS News contributor Ed Gordon put it.

For his part, Trump could be seen shaking his head, pursing his lips and furrowing his brow when Harris spoke.

He appeared reluctant to mention Harris by name — repeatedly referred to "she" and "her" — and spent little time looking at Harris, even when speaking about and to her.

In contrast, Harris directed many of her comments right at Trump and frequently turned to face him as he spoke.

One person Trump was willing to name check was President Biden, despite him no longer being in the race. He also repeatedly referred to Biden as "her boss," avoiding saying Harris' name while emphasizing the relationship between the two.

Harris didn't shy away from critiques of Trump, both with her words and her actions, from