I experience this type of dissociation multiple times every day. According to my mom I have always done this ever since I was an infant. Now it is clearly pathological (but nevertheless helpful in getting me out of situations in which I do not feel safe, e.g. people arguing in a restaurant) and I lose a lot of time. My therapist understands it and can see it. Her idea is that it will diminish as I need it less.
Sometimes I eventually come out of it by myself and have to figure out where I am and what I was doing. Other times (the most common times) I stay in this freeze state until someone slowly moves their hand about 5 feet from my face. Being stuck in this freeze mode for a while can have quite the consequences. I miss time. My eyes dry out because I do not blink throughout it. I have missed appointments or who knows what else. These severe dissociation episodes can last for days as well.
Another thing I do regularly is experience flashbacks, but those look significantly different. Some people can tell the difference while others can't. My eyes blink fast and my hands are usually involved in repetitive self stimming behaviors (e.g. flapping, wringing, something that looks like counting in ASL). Although my eyes are fixated in space, I am seeing either a movie or am fully in a past traumatic experience. People can identify facial expressions throughout the process (e.g. fear and terror as I am reliving some situations).
My therapist tries to get me out of both the flashbacks and the dissociation if it keeps going. With flashbacks I can remember the flashback and the feelings associated with it, all of which we can then process. Although both are significantly different experiences, my therapist sees the flashbacks at the high-end of activation and the episodes of dissociation at the opposite end of the activation spectrum (no activation when I need to shut out my environment). To me that makes sense.
Because of both of these symptoms, my contact alone with people in the real world is limited. I usually only go places with someone I know (e.g. PCA and friend) or alone to places where the staff knows me and knows how to respond (e.g. YMCA, therapy, bookstore). Strangers usually have no idea what they are dealing with and that they don't need to do anything. Concerned people are real and have needs as well. Even nurses are quick to identify them as different types of seizures and respond by contacting emergency services. EMS personnel can quickly find the pertinent medical information which is in my dog's pouch, but the trauma around being touched, confined, etc... puts it into a traumatic scenario. People on the not-so-healthy-minded-end of the spectrum can easily walk me away from the public and do with me whatever they would like, putting me into high-risk situations.
Yet, somehow I do manage to lead a full life... although it is different from most people... I go from times with little dissociation or flashbacks to times where the two basically replace each other depending on how triggering my experiences or my mind are.