Miley Cyrus has a phobia of wigs.

The former 'Hannah Montana' actress hates the thought of putting fake hair over her own natural locks, with her fear stemming from a previous spooky encounter.

Her friend Kelly Osbourne tweeted: ''sat with @MileyCyrus while getting my hair done & she is telling me a story about a haunted wig shop being the reason she does not like wigs (sic)''

Miley isn't the only star with an unusual phobia. Model Poppy Delevingne recently confessed to being terrified of buttons and claims to feel ''physically sick'' when she sees the clothes fastenings.

She said: ''I have a phobia of buttons - they make me feel physically sick. A girlfriend of mine once wore a pair of jeans with multicoloured buttons on the pockets. I was hugging her and grabbed her bum. I thought, 'Oh my God, what's that?' When I saw them, I went green.''

Meanwhile, The Wanted singer Siva Kaneswaran recently had his worst nightmare come true when he checked into a New York hotel room and it was decorated in a polka dot theme.

He tweeted: ''Great. Got to my hotel room and it's my worst nightmare. Polka Dots on the walls, bed sheets, floors! #SivaHatesDolkaDots #Phobia (sic).''

He's not the only boy band member to have a strange phobia, as One Direction's Niall Horan suffers from ornithophobia, a fear of birds.

He has said: ''I get really nervous if pigeons are flying around before shows.

''I can't stand them after one once flew in through my bathroom window and went for me while I was having a wee. That was enough. I think pigeons target me.''