The absence of epinephrine during REM sleep allows for the processing of challenging experiences without fear and anxiety, which is important for emotional adjustment.

“And that turns out to be very important. And you can imagine why that's important. It's important because it allows us to experience things, both replay of things that did occur as well as elaborate contortions of things that didn't occur. And it allows us to experience those in the absence of fear and anxiety, and that it turns out is very important for adjusting our emotional relationship to challenging things that happened to us while we were awake.”

“REM sleep is associated with intense experiences without this chemical epinephrine that allows us the anxiety or fear.”

“REM sleep has a certain dream component when which there's no epinephrin, therefore we can't experience anxiety, we are paralyzed. Those dreams tend to be really vivid and have a lot of detail to them.”

“So if a car suddenly screeches in front of us, or we get a troubling text message, adrenaline is deployed into our system. Adrenaline is epinephrin, those are equivalent molecules. And epinephrin isn't just released from our adrenals it's also released within our brain. So there's this weird stage of our life that happens more toward morning, that we call REM sleep, where we're hallucinating and having these outrageous experiences in our mind, but the chemical that's associated with fear and panic and anxiety is not available to us.”

“The experience in our sleep where our eyes are moving, excuse me, although in a different way, but we don't have the chemical epinephrine in order to generate the fear response, and yet we're remembering the event from the previous day or days.”

“And low adrenaline, epinephrin during REM sleep is basically a signature, a neurochemical signature of the REM sleep state, which is so vital for emotional and physical repair and so forth.”

“it's also an interesting neurochemical phenomenon because during these rapid eye movement dreams they tend to be very intense but the body can't release adrenaline so it's almost like its own form of trauma therapy it's like you're experiencing this intense thing in your mind but your body can't react”

“Rapid eye movement sleep is also important for removing the emotional load of previous day and previous days' experiences. So it's its own form of trauma therapy.”

“REM sleep is associated with intense experiences without this chemical epinephrine that allows us the anxiety or fear and almost certainly has an important role in uncoupling of emotion from experiences, kind of self-induced therapy that we go into each night.”

“And we have REM sleep, where the chemical epinephrine that allows for signaling of intense emotion and the experience of intense emotion in the brain and body is not allowed. And so we're starting to see an organizational logic, which is that a certain component of our sleeping life is acting like therapy. And that's really what REM sleep is about.”

“REM sleep has a certain dream component in which there's no epinephrine. Therefore, we can't experience anxiety. We are paralyzed. Those dreams tend to be really vivid and have a lot of detail to them. And yet, in REM sleep, what's very clear is that the sorts of learning that happen in REM sleep are not motor events. It's more about unlearning of emotional events.”

“But that bears a lot of resemblance to REM sleep, this experience in our sleep where our eyes are moving, although in a different way. But we don't have the chemical epinephrine in order to generate the fear response. And yet, we're remembering the event from the previous day or days.”