last night, i dreamt that i was at school with my friend, except we were in a different grade and school. every single detail was there; from the name of the school to what day it was. we had an assignment, to say something that we thought was cute. my friend said young love, and it reminded me of old love. i decided to tell the teacher, but she wasn't there, so i found a person on a laptop. just before i told the person what i wanted them to tell the teacher, i woke up. not realizing i was awake, i said out loud to my mom,
" old couples."
"what?"
"old couples. that's hat i think is cute. tell my teacher that i said old couples are cute."
"your teacher isn't here."
"i know. tell her when she gets back."
after that, i fell asleep immediately, and continued the same dream. it wasn't repeated, it was continued, as though i hadn't woken up. i kind of think subconsciously when i dream, as though i am watching a movie and commenting.
i was vaguely aware that something had disrupted my dream, but decided that since my dream continued, i hadn't woken up. i woke up to find that i had woken up in the middle of the night and had a conversation with my mom. i sleep talk, but i know that i definitely woke up.
every other time i've woken up from a dream and continued it later, i've always known that i had woken up.

This is normal. You seemed awake to your mother, but you were really still half asleep.

When I was younger, I once had an entire (pretty complicated) telephone conversation with someone when I was sleeping. The person on the other end had no idea I wasn't awake.

There are people who cook meals and even drive cars - safely, obeying all the rules and not getting into accidents - in their sleep. These things are very unusual, but they do happen.

There isn't always a clear distinction between waking and sleeping. You can have a mixture of being asleep and being awake. This is called a state dissociation. Some other types of state dissociations are hallucinations when you are falling aseep or waking up, sleep paralysis, lucid dreaming, out of body experiences, sleepwalking, night terrors and REM behavior disorder (where you act our your dreams in your sleep.) They aren't a problem unless you move around without knowing what you are doing so that you physically hurt yourself or another person. For example, if you dream you are in a fight and you punch someone in real life.

I honestly think that there is a sector of our brains that, when stimulated while in a REM phase, reacts to external stimuli and brings the body along for its little joy ride. Like Marcia says, you really are asleep, but to everyone else you appear just fine. I've had conversations, unlocked doors, and even changed clothes in my sleep because someone walked in and started talking to me. Because the rest of your brain is carrying on the dream, that one part of your brain makes your body play along and reasons with yourself why it makes sense to do so. Every now and then, the brain is SO convincing that either you convince yourself you woke up and really didn't, or didn't wake up and really did, all because the conditions were right and your brain made up a really good excuse. Doesn't happen often, but I'd say it's a classic case of perfect timing lol

Our page on sleepwalking might be of interest.