The reason for this is because the autistic brain tends to produce more melatonin during the day than it does at night, as opposed to a neurotypical brain that produces melatonin at night instead of during the day. Melatonin is the hormone that regulates your sleep cycle and is produced by the pineal gland in the brain. As you've probably gathered, the presence of melatonin is what makes you go to sleep, and when your melatonin levels drop that's when you wake up. The main factor that seems to trigger the release or reduction of melatonin is how light or dark it is. Autistic brains are often wired up to get this the opposite way around to the general population.
I've always had a tendency to not properly wake up until later in the day, but this really stepped up when I had kids, especially because my son was bottle fed so I did most of the night feeds. Even nowadays I find it hard to get up when my kids get up around 6:00 or 6:30am when they want me to get up. I try to drink tea (I don't like coffee even though it'd probably work better) for a caffeine boost but whatever I do I never really feel awake until just before lunch time. Conversely, my head feels by far the most awake and the most active around midnight to 1:00am. I've spent the last couple of years working until midnight until recently, which is ironic. I always feel exhausted early in the morning, but despite waking up still tired and mostly having no more than 5 or 6 hours' sleep I can't always sleep at night because my brain is too active. It's often around 1:00am that my brain processes things that have happened that day, and that I have a lot of ideas for things like blog posts or other things that I want to do. In fact, the custom vinyl figure of Christa Holmans that I made was a midnight idea.
I tried herbal sleeping tablets not long ago to try and help me sleep on a night because it was becoming a lot more frequent for me to struggle getting to sleep, but it didn't do much. I'm not sure if that's because I'm autistic but for whatever reason it didn't work. Because of things like autistic sleep patterns I think it's great that companies are moving to longer and later opening hours as well as more remote working facilities. It makes for an accessible society in terms of both customers and employees. Granted, we've mainly moved away from the standard 9-5 quite a while ago but there's still a way to go and there should be more out of hours access than there is at the moment.
I've always been quite good at sciencey subjects so I find things like the reasons for sleep cycle differences really interesting. If it's been just as interesting for you please hit the Follow button in the side bar and follow me on social media. I'm on Twitter, Facebook, Instagram, Pinterest, and you can buy me a coffee at my Ko-Fi account here.