Jamie Spears, 68, said his daughter had the condition on forms to justify controlling her finances – but fans insist it would be impossible for her to learn songs and routines if that were the case.
The singer released a song on her 39th birthday in December, Swimming In The Stars, and has released four albums and been on four global tours during her father’s ‘conservatorship’ – which gives a third party the right to manage someone’s finances.
It was set up when Britney’s conduct deteriorated after her divorce from Kevin Federline in 2007, during which she lost custody of her children Jayden and Sean.
But a documentary by journalist Mobeen Azhar, to be broadcast in the UK next week, has seen documents that show dementia may be the reason she has been living under strict legal constraints for 12 years.
Interesting: Britney Spears ‘ father Jamie claimed that his pop star daughter had dementia in conservatorship documents according to new BBC documentary The Battle for Britney: Fans, Cash And A Conservatorship reported The Sun on Friday
In The Battle For Britney: Fans, Cash and a Conservatorship, Mr Azhar says the dementia claim sounds ‘a bit out there’ and that he thought it was a ‘conspiracy theory’.
‘You have to tick a box justifying the reason and the box that is ticked, it says: ‘The order is related to dementia placement or treatment as specified’.
Those under 65 reportedly make up less than 5 per cent of dementia cases in the US leading the journalist to think it is unlikely she has the condition.