Lawrence didn't appear in any films between X-Men: Dark Phoenix in 2019 and Don't Look Up last year.
Since then, it seems, she has recovered her enthusiasm for acting.
"It feels personal for me for the first time in a long time," she told Stock.
Lawrence, now 32, made the remarks during one of the festival's "Screen Talk" events on Saturday, local time. She was in London due to her role in the new film Causeway, which tells the story of a soldier who struggles after returning home.
This is the second time Lawrence has opened up publicly in recent weeks. Speaking to Vogue for its October cover story, she spoke about becoming a mother, and the effect it may have on her career going forward.
Lawrence married art dealer Cooke Maroney in 2019, and the pair welcomed a baby boy in February of this year.
"I have had a pretty consistent theme in all my movies since I was 18," she told Vogue.
"I'm curious if, now that I'm older and I have a baby, I'll finally break out of that.
"It's so scary to talk about motherhood. Only because it's so different for everybody. If I say it was amazing from the start, some people will think, 'It wasn't amazing for me at first,' and feel bad.
"Fortunately I have so many girlfriends who were honest. Who were like, 'It's scary. You might not connect right away. You might not fall in love right away.' So I felt prepared to be forgiving. I remember walking with one of my best friends at like, nine months, and being like, 'Everyone keeps saying that I will love my baby more than my cat. But that's not true. Maybe I'll love him as much as my cat?'"
In the end, she did fall in love with her son immediately.
"The morning after I gave birth, I felt like my whole life had started over," Lawrence said.
"Like, 'Now is day one of my life.' I just stared. I was just so in love. I also fell in love with all babies everywhere. Newborns are just so amazing. They're these pink, swollen, fragile little survivors.
"Now I love all babies ... So many of my films in the past have been about my mother, my childhood. I wonder what will happen now that I'll be witnessing somebody else's childhood. And I wonder what he's going to be talking about with his therapist."
Causeway, incidentally, is releasing on November 4. You'll be able to watch it on Apple TV+ from that date.