Below is an instruction that describes a task. Write a response that appropriately completes the request. ### Instruction: Thanks for the comment. This is more comprehensive than I expected.But what I meant is, without the sleep deprivation/fragmentation, could the SpO2 drop still cause cognitive dysfunction? My nadir oxygen (lowest Spo2 recorded in my sleep study) was 88% (for a total of 9 minutes, not continuously but distributed across the night), and usually the drops are to the levels between 90-94%. If it was the sleep fragmentation caused by the Spo2 drops that is the culprit, then it doesn't really explain why I have been feeling sharper and yet I am feeling sleepy. I have had insomnia in the past and the sleep deprivation have never given me "brain fog" neither, I simply felt so tired that I can't continue with my day anymore subjectively but I wouldn't notice a "fog" over my head. One way to illustrate the difference would be the comparison between the times I had to do an all-nighter before I had OSA and when I had to do an exam after having slept say 6 hours the night before while having OSA: I still found it harder to think on my feet in the latter case even though theoretically I should be more tired in the first case due to the acute sleep loss.I don't think that my cognitive dysfunction is a placebo effect because the difference that I have noticed is a bit too big. I have taken anxiety medication (atarax) and followed the advice of a psychologist to just take it easy and relax before as well when my clinicians thought that the brain fog was caused by stress and anxiety, but even though I convinced myself that the it was psychological and even layed off my studies for a whole year, I did not experience any improvement as significant as that which I am experiencing now.I know why I am still feeling sleepy: it is from the simple fact that I get woken up by the sunlight in the morning easily, since the CPAP mask is making it hard for me to put my eye mask on and I haven't learnt to sleep under my duvet yet due to the heat underneath (the CPAP mask is making that a possibility as an added benefit anyhow).. ### Response: I don't think that there is a distinction between the SpO2 drops and the sleep awakening here. They aren't really separable since you are treating both.To whit, treating sleep apnea with oxygen supplementation isn't really effective at improving symptoms, and other causes of sleep disruption that don't cause intermittent low oxygen also result in cognitive dysfunction.I see that you are trying to separate these things out but no I don't think it is just that you are recovering from a hypoxic injury to the brain..