George Clooney blames his career start as a television actor for his refusal to listen to directors.

The Oscar-nominee - who rose to fame after starring in hospital drama ER - is thankful for his small screen roots, but prefers roles where he can follow his own emotions.

The actor/director says, "People love to knock sitcoms, but television is a great place to start. After hundreds of episodes or television as an actor, though, you become director-proof, because you're guarding the character. That's not an insult to television directors.

"Each new director wants to make the episode his Macbeth. But on ER a director would come and say, 'I think this really upsets you and you would be crying here.' And you're like, 'I cried the last three episodes.' So I trained myself not to listen to directors, because you can't."