Mayim Bialik reveals that she suffered from high levels of anxiety while filming The Big Bang Theory. The Blossom actress played Amy Farrah Fowler in the hit CBS sitcom until it wrapped up two years ago after 12 seasons. Despite the show's lightheartedness, Bialik, apparently, had a difficult time working on it, especially when she couldn't seem to perform a certain way.

Originally featuring only five main characters — Sheldon (Jim Parsons), Leonard (Johnny Galecki), Penny (Kaley Cuoco), Howard (Simon Helberg), and Raj (Kunal Nayyar) - the cast of The Big Bang Theory expanded by season 4 with the addition of Amy and Bernadette (Melissa Rauch). Since then, Bialik became an integral part of the show as she developed a romance with Sheldon. Eventually, the pair tied the knot, and by the sitcom's finale, they won the Nobel Prize in Physics for their work on Super Asymmetry. Subsequently, Young Sheldon revealed that the couple is still going strong in the future; they even confirmed that they have a son named Leonard Cooper.

Related: Young Sheldon Foreshadows Sheldon & Amy's Relationship In Big Bang Theory

Speaking on her own web series, Mayim Bialik's Breakdown (via Good Housekeeping), Bialik opened up about her time working on The Big Bang Theory. As it turns out, she's anxious about performing in general; she doesn't do well when it comes to improvisation, so it was tricky for her to be in a sitcom. The actress also said that there were times when she can't seem to perform the way the director wanted her and not getting the reaction they wanted from the live audience made it so much worse. She copes with this primarily through therapy.

"With acting stuff, my level of anxiety surrounding performing is very, very high. It's a high level of anxiety. And when I've tried to do things like improv — things that are very, kind of, free form, I freeze. I literally freeze. It's like an instant knot in your throat ... it's stuck and there are tears there. Like, I want to cry."

"I've had this a handful of times when working on Big Bang Theory when there was a certain way they wanted a line delivered, and I was like, 'Oh okay, I got that. I'll do that in the next take.' And I do it, but it's still not right. And sometimes it's like the audience isn't laughing, you know it's not funny ..."

"I can usually do about four takes or five takes before my throat starts to do that thing."

Sheldon and Amy in The Big Bang Theory season 11 finale

It's worth noting that after starring in Blossom, Bialik took a break from acting and went to school, getting her Bachelor's Degree in Neuroscience in 2000. She had a brief Hollywood comeback in 2005 but continued her studies, eventually earning her Ph.D. degree in neuroscience in 2007 — funnily, the same year The Big Bang Theory debuted. Bialik has been honest about not knowing what the sitcom was when she auditioned for it. In fact, the only reason she tried to join the comedy was that she lost her health insurance. What's curious is if she has always had anxiety about performing, or if she developed it later on.

After her long stint in The Big Bang Theory, Bialik is able to successfully transition into a new sitcom, playing the headliner in Call Me Kat. The Fox comedy also marks the second time she's collaborating with Parsons who is producing the show. Other than that, the actress is also the current interim host of Jeopardy!. However, her previous controversial comments about vaccines and Harvey Weinstein's victims are making her a divisive replacement for the well-loved Alex Trebek.

More: Young Sheldon Season 5 Needs More Than TBBT Easter Eggs & Explanations

Source: Mayim Bialik's Breakdown (via Good Housekeeping)