It has been observed that women accumulate sleep debt more rapidly than men do and might need more sleep to be functional.96–98 Interestingly, while women normally have longer and better sleep, they also report a higher incidence of sleep disorders.99–102 With regards to sleep after TBI, women often report having worse sleep outcomes after injury than men, and the female sex is considered to be a risk factor when measuring sleep disorders after injury.103–107 There are differences in orexin neuron populations between males and females. Here, HCRT is linked to sleep disorder.