Niall said: "I love it. I love the screaming. They love it, too: they're all got their tickets and they've been waiting a year or so to see you, so you've got to give it your best."
It is accepted among the boys that Harry is the recipient of the loudest screams, and while he enjoys the adulation on stage he admits it's weird when he walks into a room and girls start shrieking.
In an interview with the band in the December issue of Vogue magazine, the 18-year-old pop star said: "You're never going to get used to walking into a room and have people screaming at you. There's a lot of things that come with the life you could get lost in. But you have to let it be what it is. I've learnt not to take everything too seriously."
If Harry - who has dated several older women, including TV presenter Caroline Flack - is the heartthrob of 1D, Liam insists he is the rule breaker.
Liam - who shot to fame on Simon Cowell's pop star search show 'The X Factor' UK in 2010 with the rest of the group - won't always follow the instructions their management lay down for them, and decided to cut his hair even though he was told not to.
He revealed: "At the start, management said I wasn't allowed to change my hair. But then I did it anyway, so they kind of let that one go. I tend to change my hair quite a lot. I can go out and about. The other day I went out dressed in Adidas trainers, jogging bottoms - and no one recognised me."