'I felt I wasn't smart enough': Natalie Portman acknowledges her Imposter Syndrome.

Image: Natalie Portman at the Cannes Film Festival (Getty)

The showbiz world is full of high-achieving, Type A personalities, and Natalie Portman is undoubtedly one of them.

The 33-year-old started her film career in her early teens, going on to star in several critically acclaimed films — including the one that earned her an Oscar, Black Swan — and try her hand at directing and script-writing. Amid all this, she also studied neurobiology and advanced modern Hebrew literature at Harvard University, and launched her own line of vegan footwear.

That’s pretty damn impressive.

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Despite her obvious successes, Portman hasn’t been immune to feelings of self-doubt and depression. During a speech at Harvard’s Commencement Day, the actress spoke candidly the ‘Imposter Syndrome’ she experienced after her admission to the Ivy League establishment. (Post continues after gallery)

“When I got to Harvard just after the release of Star Wars: Episode 1, I feared people would assume I had gotten in just for being famous, and not worthy of the intellectual rigour here … I got in only because I was famous. This was how others saw me, it was how I saw myself,” Portman told the university’s current students.

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“[I felt] I wasn’t smart enough to be in this company, that every time I opened my mouth, I would have to prove that I wasn’t just a dumb actress.” We hope she now realises ‘dumb actress’ is the last way anybody would choose to describe her.

Although you mightn't be familiar with the name 'Imposter Syndrome', it's quite a common phenomenon. There's a good chance you've felt it too. Have you ever believed you were a "fraud" just waiting to be "found out"; and that any successes and achievements you've had were somehow undeserved? You don't need to be an award-winning Hollywood actress to be plagued by that kind of self-doubt.

Portman, who gave birth to her son Aleph in 2011, also acknowledged she had some "dark moments" in her earlier university days.

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"It's easy now to romanticise my time here, but I had some very difficult times here too. Some combination of being 19, dealing with my first heart break, taking birth control pills that have since been taken off the market for their depressive side effects, and spending too much time missing daylight during winter months led me to some pretty dark moments," the Dior spokeswoman said. (Post continues after video.)

"There were several occasions I started crying in meetings with professors, overwhelmed with what I was supposed to pull off, when I could barely get myself out of bed in the morning."

Portman ended her address with some stellar advice for the students sitting in front of her — but it's equally applicable to the rest of us.

“You can never be the best. The only thing you can be the best at is developing your own self. Make use of the fact that you don't doubt yourself too much right now. As we get older we get more realistic, and that realism does us no favours.”

Have you ever experienced Imposter Syndrome?