Lady Gaga "wouldn't be here" without David Bowie.

She said: "It's hard to talk about. I would never be here without him -- I would've thought I was too weird -- and I never gave up because I thought he was the coolest ever."

Gaga will also be performing at the Oscars and is pleased 'Til It Happens to You', which she co-wrote with Diane Warren for 'The Hunting Ground' - a documentary which tackles issues surrounding campus rapes in American educational institutions - has been nominated for Best Original Song because it tackles an important subject.

She told 'Extra': "It's actually very personal -- it's so important to us. We are so grateful that the Academy cares about this issue, because you can't nominate this song without nominating the issue."

At the weekend, the 'Poker Face' hitmaker performed the US national anthem at the Super Bowl and doesn't think there can be a greater "honour" than singing 'The Star-Spangled Banner' in public.

She said: "I was nervous, but I was really excited.

"Those athletes were just so in the zone and getting pumped up and the stadium energy was magnificent. There is really no greater honour than singing for your country."