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SUZANNE CORKIN (à) PERMANENI The man with no memory, and what he taught the world “rich with implications for our brain, our experience and STEVEN PINKER 'Fascinating . understanding of the what it means to be human 70% Contents List of insert Figures Prologue: The Mem Behind the Initials 1. Prelude to Tragedy 2.ºA Frankty Experimental Operation” 3. Penfieid and Milner 4. Thirty Seconds 5. Memories Are Made of This 6. “An Argument with Myself” 7. Encode, Store, Retrieve 8. Memory without Remembering I: Motor-skill Leaming 9. Memory without Remembering II: Classical Conditioning, Perceptual Learning, and Priming 10. Henry's Universe 11. Enowing Facts 12. Rising Fame and Declining Health 13. Henry's Legacy Epilogue Illustrations Nates Acknowledements Follow Penguin Suzanne Corkin PERMANENT PRESENT TENSE The Mem with No Memory, and What He Taught the World List of Insert Figures 1. Limbic system. This image is a work of the United States Government (NIH) and is in the public domain falling under Image License B defined under the Image License section of the Disclaimer page. 2. Four lobes of the cerebral cortex. Courtesy of Andrê van der Koumwe, Jean Augustinack, and Evelina Busa. 3a Medial temporal lobe structures. Courtesy of Andrê van der Kouwe, Jean Augustinack, and Evelina Busa. 3b. Hippocampus, entorhinal cortex, and perirhinal cortex. Courtesy of Andrê van der Kouwe, Jean Augustinack, and Evelina Busa. 4. Henry's MRI. 8. Corkin etal., “HM.'s Medial Temporal Lobe Lesion: Findings from Magnetic Resonance Imaging,” Journal of Neurosciencel 7 (1097): 3064-70. 5. Mooney Face-perception Test. B. Milner et al., “Further Analysis of the Hippocampal Amnesic Syndrome: 14-Year Follow-up Study ofHAM)” Neuropsychologia 6 (1968): 215 34. 6a Visual stepping-stone maze. B. Milner et al. “Further Analysis of the Hippocampal Amnesic Syndrome: 14-Year Follow-up Study ofHM,” Neuropsychologia 6 (1968): 215 34. Gb. Tactual stylus maze. 25. Henry, 1975. 26. Henry ready for testing at MIT. Photograph by Jenni Ogden, 1986. 27. Henry at Bickford Health Care Center. 28. Henry's drawing of the floor plan of his home. 5. Corkin, “What's New with the Amnesic Patient HM Nature Reviews Neuroscience 3 (2002): 153-160. 29. Henry"'s spoon. Prologue The Man Behind the Initials Henry Molaison and I sat opposite each other, a microphone on the narrow table between us. Parked next to him was his walker, and the white basket attached to the front held a book of crossword puzzles; he alwavs kept one close by. Henry wore his usual attire—pants with an elastic waist. à sport shirt, white socks, and sensible black shoes. His large face, partly covered by thick glasses, wore a pleasant. attentive expression. “How are vou feeling today)” I asked him. “ feel okay,” Henry replied. “That's good. You look great.” “Well. thank you.” “Tunderstand that you have a hiítle trouble remembering things” “Yes, 1 do. I do have-—well, a lot of trouble remembering things. vou know. And one thing I found out that 1 fool around with a lot is crossiword puzzles. And, well, 1t helps me in a way.” new memories and, in doing so, determined the course of the rest of his life. Amnesia is the inability to establish lasting memories that are later available for conscious retrieval. The words origin 15 n the Greek amresia, meaning forgetfulness or loss of memory. but the deficit goes beyond forgetting. Amnesic patients such as Henry are stripped of their ability to tum their immediately present experiences into lasting memories. This condition, which may be permanent or temporary, tvpically stems from an insult to the brain, such as encephalitis, stroke, or head injury. Amnesia can also arise from a rare psychiatric disorder, psvchogenic amnesia, whuch has no identified nevrological cause. In Henry's case, the amnesia resulted from the surgical removal of pieces of his brain, and 1t was permanent. Henrv was a voung man of twenty-seven when he had the operation. Now sixty-six, he relied on a walker to prevent falls. But to him, only a short time had passed. In the decades after his operation, he lived in a permanent present tense: he could no longer remember the faces of people he met, places he visited, or moments he lived through. His experiences slipped out of his consciousness seconds after they happened. My conversations with Henry vanished from his mind immediately. “What do vou do during a typical day?” “See, that's tough—what I don't ... I don't remember things.” “Do you know what you did yesterday?” “No. 1 don't.” “How about this morning?” “ don't even remember that.” “Could vou tell me what vou had for lunch today” “T don't know. tell you the truth. [m not— “What do vou think you'll do tomorrow?” “Whatever's beneficial,)” he said in his friendly. direct way. “Good answer,” 1 said. “Have we ever met before, vou and 12º “Yes, I think we have.” “Where?” “Well, in high school” “In high school?” “Yes. “What high school?” “In East Hartford.” “Have we ever mei any place besides high school” Henry paused. “Tell you the truth, 1 can't—no. I don't think so.” At the time of our interview, I had been working with Henry for thirty vears. 1 first met him in 1962, when L was a the first psychologist to test Henry after his operation, and her 1957 paper with Scoville, describing Henry's operation and its awful consequences, revolutionized the science of memory” I was trving to expand the scientific understanding of Henry's amnesia by examining his memory through his sense of touch, his somatosensory system. My initial investigation with him was focused and brief, lasting one week. After [moved to MIT, however. Henry's extraordinary value as a research participant became clear to me, and 1 went on to study him for the rest of his hfe, forty- six years. Since his death, I have dedicated my work to linking Aftv-five years of rich behavioral data to what we will learn from his autopsied brain” When I first met Henry. he told me stories about his early life. 1 could instantly connect with the places he was talking about and feel a sense of his hfe history. Several generations of my family lived mm the Hartford area: my mother attended Henry's high school, and my father was raised m the same neighborhood where Henry lived before and after his operation. 1 was born in the Hartford Hospital, the same hospital where Henry's brain surgery was performed. With all these intersections in our backgrounds and experiences, it was interesting that when 1 would ask him whether we had met before, he typically replied, “Yes, in high school” I can only speculate as to how Henry forged the connection between his high-school experience and me. One possibility is that 1 resembled someone he knew back then: another is that during his many visits to MIT for testing, he gradually built up a sense of familianity for me and filed this representation among his high-school memories. Henry was famous, but did not know it. His striking condition had made him the subject of scientific research and public fascination For decades, I received requests from the media to interview and videotape him. Each time I told him how special he was, he could momentarily grasp, but not retam, what 1 had said. The Canadian Broadcasting Corporation recorded our 1992 conversation for two radio programs, one devoted to memory. the other to epilepsy. A vear earlier, Philip Hilts had written an article about Henry for the New York Times. and later made him the focus of a book, Memory 's Ghost.* Scientific papers and book chapters were written about Henry, and his case is one of the most frequently cited in the neuroscience literature. Open any introductory psychology textbook and vou are likely to find somewhere in its pages a description of a patient known only as HM. next to diagrams of the hippocampus and black-and-white MRI images. Henry's disability, a tremendous cost to him and his family. became science”s gain. our memory to get us through each moment and each day. We need memory to survive — without 1t, we would not know how to clothe ourselves, navigate our neighborhoods, or communicate with others. Memory enables us to revisit our experiences, to learn from the past, and even to plan what to do in the future. It provides continuity from moment to moment, morning to evening. day to day, and year to vear. Through Henry's case, we gained insights that allowed us to break memory down into many specific processes and to understand the underlying brain circmits. We now know that when we describe what we had for dinner last night. or recite a fact about European history, or type a sentence on à keyboard without looking at the keys. we are accessing different types of memory stored in our brains. Henry helped us understand what happens when the ability to store information is missing. He retained much of the knowledge he had acquired before his operation, but in his daily life afterward, he depended heavily on those around him. His family, and later the staff at his nursing home, remembered what Henry had eaten each day, what medications he needed to take, and when it was time for a shower. His test results, and medical reports, and the transcripts of his interviews, helped preserve information about his life that he could not retam. Of course, none of these resources could substitute for the capacities Henry had lost. For memory does more than just help us survive-t influences our quality of life and helps shape our identity. Our identity is composed of narratives we construct based on our personal history. What happens 1f we can no longer hold our experiences in our brain long enough to string them together? The link between memory and identity lies at the heart of our apprehensions about aging and cognitive decline. Losing our memory to dementia seems an unimaginable misfortune, vet this 15 what all of adult life was like for Henry. As his present moved forward, it left no trail of memory behind, like a hiker who leaves no footprints. How could such a person ever have a clear sense of who he was? Those of us who knew Henry recognized a clear personality—gentle, goodhearted, and altruistic. Despite his amnesia, Henry had a sense of self. But it was skewed. weighted heavily toward his general knowledge of the world, his family, and himself before 1953. After his operation, he was able to acquire only the smallest fragments of self-knowledge. We can describe memory in all the ways we confront it im our lives. But how do our experiences translate into mechanisms in the brain? Memory is not a single event, not a snapshot fixed in celluloid with the click of a shutter. We have learned —initially from Henry—that memory does not 
