Unforgettable A Nobel-winning neurologist's favorite books on memory. BY ERIC KANDEL Saturday, April 7, 2007 12:01 a.m. 1. "Ficciones" by Jorge Luis Borges (Grove, 1962). Memory is the scaffold that holds our mental life together. One of its most remarkable characteristics is that it has no restraints on time and place. Memory allows you to sit in your living room while your mind wanders back to childhood, recalling a special event that pleased or pained you. This time-travel ability, often sparked by a sensory experience that opens the floodgates of memory, is central to much great fiction. It is described in the most detail in Marcel Proust's million-word classic, "Remembrance of Things Past," in which a madeleine dipped in tea famously prompts an onrush of images from the protagonist's childhood. But one of the most fascinating descriptions of memory in fiction can be found in Jorge Luis Borges's seminal short-story collection, "Ficciones," first published in 1945 in Spanish. Borges, who knew for much of his life that he was slowly going blind from a hereditary disease, had a deep sense of the central and sometimes paradoxical role of memory in human existence. This sense informs much of "Ficciones" but particularly the story "Funes, the Memorious," which concerns a man who suffers a modest head injury after falling off a horse and, as a result, cannot forget anything he has ever experienced, waking or dreaming. But his brain is filled only with detail, crowding out universal principles. He can't create because his head is filled with garbage! We know that an excessively weak memory is a handicap, but, as Borges shows, having too good a memory can be a handicap as well--the capacity to forget is a blessing. 2. "Memories Are Made of This by Rusiko Bourtchouladze (Columbia, 2002). There are several good introductions to the biology of memory storage for the general reader, but I particularly like Rusiko Bourtchouladze's. A gifted writer who is also a behaviorist, she discusses both of the great themes of memory research: the "systems problem" of memory storage (the areas of the brain recruited for different forms of memory) and the "molecular problem" (the molecular mechanisms whereby memory is stored at each site). In considering the system problems of memory, Bourtchouladze describes the now famous patient called H.M., who underwent brain surgery that left him with a devastating memory loss. H.M. could not store any new information about people, places and objects. The great Canadian psychologist Brenda Milner studied H.M. and, in a classic analysis carried out over two decades, succeeded in localizing this component of memory storage to the medial temporal lobe. Bourtchouladze brings these riveting discoveries to life. 3. "Memory and Brain" by Larry R. Squire (Oxford, 1987). "Memory and Brain" is a classic in the biology of memory. In it, Larry R. Squire, a professor of psychiatry and neuroscience at the University of California at San Diego, provides a superb historical overview of the key experiments and insights that have given rise to our current understanding of the problem of memory storage. Squire himself has played a vital role in this history: He pioneered our understanding that memory exists in two major forms: declarative memory (this is the kind of memory that H.M. lost) and procedural memory (for motor and perceptual skills such as riding a bike or hitting a backhand--this is the memory that H.M. retained). His later work includes such breakthroughs as identifying the hippocampus in the medial temporal lobe as critical for the storage of declarative information. 4. "The Seven Sins of Memory" by Daniel L. Schacter (Houghton Mifflin, 2001). In "The Seven Sins of Memory: How the Mind Forgets and Remembers," Harvard professor Daniel L. Schacter shows that declarative memory (the kind involving people, places and objects) is highly fallible and susceptible to distortion and suggestion. The seven "sins" refers to memory's various weaknesses: its transience, absentmindedness, blocking, misattribution, suggestibility, bias and persistence. Schacter, another pioneer in the study of human memory, employs his insights not only to reveal the fragility of memory and its extraordinary vulnerability to influence by authority figures but also to indicate effective ways of understanding how memory is normally encoded. 5. "Memory From A to Z" by Yadin Dudai (Oxford, 2002). Any question that remains unanswered after reading the above works by Bourtchouladze, Squire and Schacter can be answered by Yadin Dudai, a professor at the Weizmann Institute in Israel. This is an entertaining, wide-ranging and well-written primer (subtitle: "Keywords, Concepts and Beyond") with more than 130 entries that range from discussions of memory on the molecular level to examinations of the philosophical issues that confront researchers. "Memory A to Z" begins with "A priori" and runs through subjects such as "False Memory," "Metamemory" and "Synapse," before ending at "Zeitgeist." The book is a handy reference, accessible to the general reader. Dr. Kandel is University Professor in the Center for Neurobiology and Behavior at the Columbia University College of Physicians and Surgeons. He is the author of "In Search of Memory: The Emergence of a New Science of Mind" (Norton, 2006). He won the Nobel Prize in Physiology or Medicine in 2000 for his studies of memory.