2/2Examining the curious case of a man whose memory was removed (脳の記憶部分摘出ー書評)

Scoville, meanwhile, had become a vocal proponent and prolific performer of psychosurgeries;by the time he began treating Molaison in the mid-1940s, he was a participant in a study that lobotomize mentally ill patients in the hope of easing overcrowding in Connecticut's asylums. But it wasn't until 1953 that Scoville drilled into Molaison's skull. Why the delay? One obvious answer is that Scoville had initially tried, and failed, to control Molaison's seizures with medication. Mr. Dittrich speculates that there was another, more sinister explanation. In the era of early brain mapping, when identifying the function of a specific region could secure lasting glory, Scoville had become frustrated with the limitations of operating on patients with acute psychological problems. What could removing a portion of the brain in someone who wasn't “normal” possibly tell him about the role of that area in someone who was healthy?
Molaison, however, was psychologically intact - but the locus of his seizures was unknown. “Lacking a specific target in a specific hemisphere of Henry's medial temporal lobes, my grandfather had decided to destroy both,” Mr. Dittrich writes in one of the book's many chilling passages. “The risks to Henry were as inarguable as they were unimaginable. The risks to my grandfather, on the other hand, were not. At that moment, the riskiest possible option for his patient was the one with the most potential rewards for him.” This is heavy stuff:Mr Dittrich ultimately puts his grandfather's actions on a continuum with those of Nazi doctors who tortured Jews to test the limits of human endurance. While that comparison is a bit strained - Molaison was, after all, a willing patient who was actually sick - Mr. Dittrick does make a convincing (if implicit) case that Scoville violated the Nuremberg Code adopted in the wake of World War II to govern re
search on humans.
Mr. Dittrich's righteous indictment of his own grandfather is undeniably powerful. Of the two most compelling acusations of medical and scientific misconduct in “Patient H.M.,” it's also the one that has been aired before. But Mr. Dittrich also raises a number of issues relating to Suzanne Corkin's actions, including whether she received informed consent for her tests on Molaison.
Corkin. who died of liver cancer in May, first encountered Molaison in the 1960s, when she was a graduate student in Montreal, but it wasn't until 1977 that she fully took over his case. Over the following decades, Corkin and more than 100 collaborators conducted countless experiments, many of which involved activities a typical test subject would find invasive or unpleasant.
The entire reason Molaison was given these tests was that he was incapable of remembering more than 20 or 30 seconds in the past - and yet for 12 years, from 1980 until 1992, Molaison signed his own consent forms. At that point, Mr. Dittrich writes, Corkin arranged for the son of Molaison's former landlady, who may have been a distant relative, to serve as his conservator despite the fact that Molaison had several first cousins living nearby.
Mr. Dittrich also appears to have uncovered evidence that Corkin's published work painted an incomplete picture of Molaison. In her book, Corkin described Molaison as carefree and easygoing, a sort of accidental Zen master who couldn't help living in the moment. In one of her papers, which make reference to but does not quote from a depression questionnaire Molaison filled out in 1982, Corkin wrote that Molaison had “no evidence of anxiety, major depression or psychosis.” Mr. Dittrich located Molaison's actual responses to the questionnaire, which had not been included in Corkin's paper. Among the statements Molaison circled to describe his mental state were “I feel that the future is hopeless and that things cannot improve” and “I feel that I am a complete failure as a person.”
That disclosure raises the question of whether there is more unpublished information that could yield new insights into Molaison. Corkin, however, told Mr. Dittrich in a recorded interview that she was shredding her files on Molaison lest future researchers misinterpret her data. When several of these revelations appeared in a New York Times Magazine excerpt from Mr. Dittrich's book, Corkin's former colleagues, at M.I.T. and elsewhere, cried foul. The question of whether files were actually destroyed remains unsettled, while the issue of informed consent has not yet been addressed. (I am a professor at M.I.T.;I did not know Corkin and don't know any of the principals involved in the response to Mr. Dittrich's work.)
The fact that Mr. Dittrich looks critically at the actual process of scientific investigation is just one of things to admire about “Patient H.M.” It also makes its most glaring shortcoming all the more incomprehensible:This deeply reported, 400-page book, which aims to reframe one of the best-known medical case studies of the 20th century, is devoid of either source notes or a bibliography. That's inexcusable:Given the number of ways in which Mr. Dittrich's narrative differs dramatically from what's been published before, he has a responsibility to show readers how he came to his conclusions.
Molaison has long been portrayed as the victim of a surgeon's hubris. Mr. Dittrich's book, and the reaction to it, highlight why the lessons learned from his life cannot be limited to those stemming from a single act in the distant past. With most of the principals in the tragedy of “Patient H.M.” now gone, the question at the core of Mr. Dittrich's story - did the pursuit of knowledge conflict with the duty of care for a human being? - remains, in every interaction between science and vulnerable subject.