There was a patient named Donald who murdered his girlfriend while he was high on PCP. Donald claimed to have no memory of the murder, and at his trial his lawyers successfully pled insanity. Donald spent four years in a psychiatric hospital for the criminally insane. In the hospital, he took an active interest in gardening. He seemed calm, and his doctors guessed that, somehow, he’d achieved “a sort of stability.”
Sacks doesn’t editorialize on whether or not Donald actually went insane under the influence of PCP; however, there have been many cases of people losing their memories and inhibitory instincts under the influence of PCP or other similar drugs. Indeed, even the sober mind sometimes blocks out unpleasant memories, so that the individual can achieve “a sort of stability.”
Donald became so stable that he was allowed to leave the hospital on weekends. One weekend, Donald took a bike ride and sustained a severe head injury, which left him in a coma for two weeks. After he regained consciousness, Donald was plagued by hallucinations of the act of murdering his girlfriend. Where before Donald claimed to have forgotten any memory of the deed, he could now remember the deed in almost photographic detail. Donald became so racked with guilt and anxiety that he twice tried to kill himself.
The fact that Donald could suddenly remember killing his girlfriend in such vivid detail suggests that the memory of the incident was never truly lost; instead, Donald repressed his memories of the incident, at least until his head injury caused his memories to “escape” once again.
What caused the sudden change in Donald’s behavior? EEG tests suggested that Donald experienced near-constant seizures in both temporal lobes, perhaps inducing his hallucinations. However, over time, Donald learned to control his hallucinations with the help of therapists. Donald still experiences visions of his murder, but he’s no longer “obsessed” with these visions—he’s learned how to live with them. But the real mystery, Sacks concludes, is why Donald lost the memory of the murder in the first place.
As with many of the patients in this book, Donald doesn’t “defeat” his neurological disorder; he just learns to live with it, thanks to the therapy and training he receives in the hospital. Sacks acknowledges that he—and the neurological community in general—doesn’t understand exactly why Donald forgot the murder to begin with (and if he did, Donald probably wouldn’t have needed training).