The operation was successful, but not long after Campbell returned home, her mother sensed that something was wrong. The calm, precocious girl who went into the surgery was not the same one who emerged. Campbell began flinging food from her high chair. She suffered random episodes of uncontrollable vomiting. She threw violent temper tantrums during the day and had disturbing dreams at night. “They were about people being cut open, lots of blood, lots of violence,” Campbell remembers. She refused to be alone, but avoided anyone outside her immediate circle. Her parents took her to physicians and therapists. None could determine the cause of her distress. When she was in eighth grade, her parents pulled her from school for rehabilitation.

...Many of these cases are benign: vague, hazy flashbacks. But up to 70 percent of patients who experience awareness suffer long-term psychological distress, including PTSD—a rate five times higher than that of soldiers returning from Iraq and Afghanistan. Campbell now understands that this is what happened to her, although she didn’t believe it at first....The lawsuit claimed that Sizemore was tormented by doubt, wondering whether he had imagined the horrific pain. No one advised Sizemore to seek psychiatric help, his family alleged, and no one mentioned the fact that many patients who experience awareness suffer from PTSD. On February 2, 2006, two weeks after his surgery, Sizemore shot himself. He had no history of psychiatric illness.

...Doctors began investigating how anesthesia affects consciousness during the 1960s, shortly after the first reports of awareness. One South African researcher was especially curious about whether and how one might recall memories from a surgery. Perhaps a near-death experience? Pushing well beyond the limits of what would today be considered ethical, he collected 10 volunteers undergoing dental surgery. The procedures went along as normal until, midway through, the room went silent and the medical staff reached for scripts....Of the 10 volunteers, four remembered the words accurately; four retained vague memories; and two had no recollection of the surgery. The eight patients who did remember it displayed anxiety during the interview, many of them bursting from hypnosis, unable to continue. But when out of hypnosis, it was as though nothing had happened. They had no memory of the incident. The terror and anxiety seemed permanently buried in their subconscious.

"Awakening", Atlantic