Are we conscious when we are asleep?
Bernard Norman
London, UK
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This issue is complicated because it raises the question of what consciousness is. (Although, as an aside, my pet chickens know where they are in their pecking order, so appear to be self-aware and therefore conscious.)
I work as an anaesthetist and would argue that one is conscious when asleep. On waking in the morning, one is aware of events during the night, even if not fully woken up by them (for example, a partner joining you in bed or a rainstorm outside).
In addition, there is awareness of the passage of time since the evening before, when you went to bed. Compare this with the drug-induced coma of general anaesthesia. On waking, the patient is completely unaware that time has passed and will often think they haven鈥檛 had surgery, even if it has taken many hours.
You are conscious when asleep, but not when anaesthetised. The problem with alcohol or sleeping pills prior to bed is that the resultant 鈥渟leep鈥� is more akin to anaesthesia, and therefore the background processing of information is inhibited, making the sleep less restorative.
David Bortin
Whittier, California, US
The simple answer is yes, we are conscious when we are asleep.
There seems to be no authoritative consensus on the definition of consciousness, but most would agree that it can鈥檛 be a simple binary (on or off) state. If it is acknowledged that consciousness correlates to receptivity and responsiveness to sensory input, then there must be at least three measurably different levels: awake, asleep and dead. Otherwise, alarm clocks wouldn鈥檛 work as they do.
In my opinion, a useful definition would be one that allows for a hypothetically quantifiable measure of at least one dimension of consciousness, much like that for intelligence. have to measure consciousness instrumentally 鈥� with less than satisfactory results so far. These considerations have taken on a new urgency with the question of whether artificial intelligence is or can ever become conscious. Perhaps 鈥渓iving鈥�, 鈥渂iological鈥� or even 鈥渂rain鈥� should have a place in the definition, possibly as a second dimension. Then there is the philosophy of panpsychism, which argues that no material object is completely without consciousness.
Another intriguing tangent to explore from the 鈥渨hat is consciousness?鈥� enigma is 鈥渨hy is consciousness?鈥� This intersects with the philosophy of hard determinism, wherein it is believed that all events are determined by a chain of prior causes. Consciousness in such a world view would be like watching a movie with full awareness of the course of events, but being totally powerless to alter the script. Might consciousness 鈥� whatever it is 鈥� have evolved purely for its entertainment value?
Gillian Peall
Macclesfield, Cheshire, UK
If we can be prodded awake in order to act and/or think, then we are conscious while asleep, as opposed to being anaesthetised or unconscious due to a brain injury. So long as we can be classed as a living, breathing sentient being, then we are conscious as opposed to dead. But it all depends on your use of the word 鈥渃onscious鈥�.
Mark Thompson
Tewkesbury, Gloucestershire, UK
We lose consciousness when we fall asleep, at least until we start to dream. It is widely believed that dreams occur only in rapid eye movement (REM) sleep. Thus, it can be assumed that there is no sleep consciousness outside REM sleep. Although, interestingly, my wife always fully remembers her dreams (and tells me about them every morning). I, on the other hand, rarely remember my dreams, but I can lose consciousness during the better half鈥檚 retelling.
Gregory Wlodarski
Via Facebook
It depends on your definition of consciousness. If you consider consciousness to be awareness of and the ability to respond to changes in the environment, then no, you aren鈥檛 conscious while asleep. But if the definition is having mental activity, then the answer is yes, at times, depending on the sleep stage.
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