Vulnerability to alertness failure in response to sleep deprivation in people with obstructive sleep apnoea

A series of measurements relating to vulnerability to altertness failure will be undertaken at two laboratory visits, one week apart: (1) baseline visit, with measurements undertaken in the evening of the visit, throughout the night and in the morning of the baseline visit (2) an extended wakefulness (sleep loss challenge) visit Details of the extended wakefulness intervention: Each participant's wakefulness will be extended by 3 hours based on their habitual sleep onset time (which will be determined using actigraphy and sleep diary sent to the participants one week prior to their baseline visit). Measurements will be undertaken in the evening of the visit, throughout the night and in the morning.