One of the reasons it’s hard to keep track of time or even a sense of time during dreams is because the prefrontal cortex part of the brain isn’t active. The prefrontal cortex has a key role in memory.
There’s also a lot of self-reference in dreams – the idea that things are being cleared up before you. And it can be hard to recognise inconsistencies because this imagery is being generated internally and it does seem to jump around a lot. You don’t seem to notice that in the dream itself, you tend to think about it more when you wake up. At least I do anyway. And I think it’s to do with your lack of self-reference almost when you’re asleep. You can’t recognise that it’s not real and has been generated internally.
"With lucid dreaming the frontal areas of your brain are reactivated, like they are when you’re awake, and with that it means you get an increased sense of the flow of the dream."
I think for lucid dreamers the narrative can be more continuous – almost like you’re awake. And many can control the scenes as they play themselves out. With lucid dreaming the frontal areas of your brain are reactivated, like they are when you’re awake, and with that it means you get an increased sense of the flow of the dream. You can recognise yourself and that you’re actually in a dream environment. But when you don’t have a lucid dream, you’ve lost this frontal activity and consequently you don’t get that sense of you or the narrative at all.
It’s been described as the difference between primary consciousness and secondary consciousness. The primary consciousness is what you get when you’re in a regular dream – you can have emotions and sensations and stuff, but you don’t really have any thoughts of self, you don’t really have any self-awareness or any notion of things happening now. Secondary consciousness is what we have when we’re awake and also when we lucid dream – and there are certainly references to the self within this.
Our perception of time is skewed when we dream – almost completely. Whatever mechanisms control our time perception; they aren’t active when we’re dreaming. At least not in the way that they are when we’re awake. That’s certainly one of the reasons dreams can be ramshackle and skewed, because we have no way of recognising it in a linear fashion. And that certainly applies to most people’s non-lucid dreams. Again you do get individual differences and degrees of randomness and lack of linearity. People that are more aware that they’re dreaming report higher instances of linear dreams. If you’re well versed in dreaming and can distinguish a dream from when you’re awake, so you know that time is going to work a little more strangely.