This type of memory loss is called Memory Hack Review retrograde amnesia which eliminates any memory of events prior to the accident. It may only be for the preceding few minutes, hours or days rather than the more unusual extensive period that my partner experienced. When he became more aware, after ten days in a medically induced coma, he thought it was ten years in the past. He had no recollection at all of his accident and had lost ten years of his memory.
This was a traumatic experience for me, as I'm sure it was for him because during this ten year amnesia period, his wife had died and we met each other only three years prior to his accident. When I visited him, there were times that he knew my name and other times when I asked him if he knew who I was that he avoided my question. But even when he seemed to know my name, I don't think he had any real understanding of what our relationship meant to him. Even after he had been out of the hospital for several months and appeared to have recovered most of his memory of that ten year period, he admitted that he had no accurate realization of what our relationship had been like prior to his accident. This was very disconcerting.
This period was a learning experience for him. When I asked him how old he was, he gave me the age he would've been ten years previously. There were many friends who visited that he didn't recognize including some he had known for twenty plus years. He had no memory of the new home we had moved into, still thinking he lived where he had for many years prior. He also had no memory of the year or make of car that he drove instead telling me about one he had driven years before.
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