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The Sevens Sins of Memory

Memory’s Fallibility

By Izzat Jarudi

staff writer

Written by Daniel Schacter

Published by Houghton Mifflin


It is not an obscure fact among people of all cultures, times, and disciplines that memory is critical to human identity. Memories store the past -- our former thoughts and experiences -- and thus define how we feel and act in the future. What is less understood about the mechanism of memory, however, is how the brain manages the flood of sensory information that a human being confronts every day. How are relevant pieces of information selected from among the deluge and organized for later conscious retrieval in long-term memory?

Daniel Schacter, chairman of the Psychology Department of Harvard University and one of the world’s experts on memory, offers the best answer I have encountered to that question in his new book The Seven Sins of Memory. He not only presents a lucid synthesis of current research on how the mind remembers, but also on how the mind forgets.

We become most aware of our memory when it fails us, when we forget where we put our keys or when we remember something differently from the way it happened. Schacter recognizes that tendency and structures his discussion of memory around seven of its “sins” -- transience, absent-mindedness, blocking, misattribution, suggestibility, bias, and persistence.

The first three are “sins of omission” in which we can’t remember something we want to remember. Transience occurs when memories fade over time, absent-mindedness when we don’t pay enough attention to what we need to remember, and blocking when we can’t spit out a name or word that is on the tip of our tongue.

The last four are “sins of commission” in which we remember something but it is either distorted or unwanted. These tend to be less innocuous with profound implications for the legal system, from the reliability of eyewitness testimony to the frequency of false confessions. Misattribution occurs when we confuse the source of a memory, suggestibility when a false memory is implanted as a result of leading questions, comments, or suggestions, bias when our current knowledge and beliefs lead us to revise memories of our previous experiences, and persistence when memories of disturbing events linger despite our best efforts to forget them.

Schacter devotes a chapter to each sin, discussing their consequences for our lives and our understanding of memory through vivid examples from history, current events, and everyday life as well as an effective review of the scientific literature. In addition, he considers ways to counter memory’s sins, both assessing current methods (including popular approaches like taking gingko to reduce transience) and presenting his own ideas.

Schacter ends his book with some speculation about the origins of these lapses, mistakes, and distortions of memory. After filling two hundred pages with a discussion of memory’s imperfections and the harmful effects they can have on our lives, he anticipates an interesting question: Isn’t this evidence of poor system design by natural selection? He explains why he still believes that “memory is a mainly reliable guide to our pasts and futures” by arguing that “each of the seven sins is a by-product of otherwise desirable and adaptive features of the human mind.” After all, not everything about us is adaptive. For example, Schacter explains that the sin of persistence may be the painful consequence of a memory system that doesn’t let us forget events that could threaten survival.

Clearly, this book is not only for students in Course IX (Brain and Cognitive Sciences), although I wouldn’t be surprised if it become required reading for classes in that department very soon. Schacter has written a comprehensive (and concise) book on memory, accessible to anyone interested in how science today thinks we remember and forget the past. He simply does everything right in The Seven Sins of Memory, with elegant writing that smoothly integrates a discussion of current memory research with its undeniable impact on all our lives.