Are we aware of our surroundings when we sleep?

Are we aware of our surroundings when we sleep?

The brain's analyzing information all the time, even when we are asleep. And making decisions as to whether we should awaken or not and attend to the sounds. An example of that is thinking about how a baby's whimper will invariably awaken a parent whereas a snorer who can generate industrial levels of noise won't awaken themselves. Another example of that is, if you're in dreaming sleep, and experimentally provide somebody with emotionally salient material, then it will get incorporated into their dream. An example might be something like if you provide the name of somebody's parent, that parent will then probably arise in the dream so you let them dream for ten, fifteen minutes, and you awaken them and they'll tell you about it.