Nearly everyone who drives experiences some highway hypnosis as mentioned in an earlier post. This might include blanking out for a few exits or "waking up" long past your exit or after a lengthy (more than 10 minutes) period of time.
So when you are "zoned out", who is driving the car? What happens that you are still driving safely, haven't run off the road, been in an accident. You aren't consciously there.
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What scenery can you identify from the time you blank out until you "wake up"? You won't remember because it is not your memory. The aspect of you who drove holds that memory. We all have a safe driver somewhere inside who takes over at those times, thank goodness. Do you believe you must also have a homicidal part because you experienced a dissociated state of a driving part? Are you afraid to share your experience with friends or family? Generally highway hypnosis is an open topic. We all do it so it's acceptable even though it is experiencing a dissociative state.
So why is it that someone who dissociates because of long-term childhood abuse is feared and dismissed and devalued as a human being by society? Just something to think about.