Well...we do always remember having a good night's sleep! That requires consciousness. It is Consciousness that has experienced the good nights sleep. And the fact that you wake up as the same person you were before shows the consciousness did not really die during the sleep. It was merely unconnected. Like switching off the wifi. So...saying that Consciousness does not SURVIVE falling asleep is wrong.
Many people sleep walk..... when their subconscious/unconscious mind stays awake though the person does not remember the event. This shows part of our consciousness stays awake even when we sleep. The Unconscious mind is part of our Consciousness. We cannot ignore it.
A number of inaccuracies and misunderstandings there Sriram, and I suppose my previous post was also somewhat sloppily worded.
Consciousness is something that admits of degrees, it is not an either/or thing, in fact we measure its strength now by an index, the perturbational complexity index, or pci for short. It normally reduces during sleep and is maximised during states of high alert and minimised or even zero under general anaesthesia or coma or dreamless sleep. We tend to think of being awake and consciousness as being the same thing but that is not really true either; people in a vegetative state have periods of sleep and wake, but they are not conscious whilst awake.
I think you are mixing up memory with consciousness. Consciousness does not 'experience' anything, rather it is a synthesised retrospective experiential phenomenon of what the (unconscious) body collectively experienced just a moment ago. The fact that we wake up feeling the same person as when we went to sleep is due to memory retention, not the persistence of consciousness during sleep. There are occasional islands of conscious experience during sleep, we call them dreams.
There is nothing in the current flood of research that would support a notion of consciousness as being somehow a separate thing from the body, rather it is a process produced by a complex biological system and this process evolved primarily to provide a service of
interoception, ie a holistic registering of the internal state of the body derived from data procured by a central nervous system; complex living bodies produce consciousness just as they produce many things, perspiration, for instance, and the idea of a consciousness separate from a body makes no more sense than the idea of perspiration existing independently of the body producing it.