Britney Spears’ mental state has been compared to that of a comatose patient by her lawyer, according to reports.The Toxic singer, 38, is said to be unable to sign a sworn declaration in her conservatorship case in a hearing on Wednesday 7 October. It was claimed Britney doesn’t want to perform again, after cancelling her Las Vegas residency last year, but her father Jamie, 68, is said to be pushing for her to continue to record and perform music.