Memories are made of this

The issue of what is remembered and what forgotten is a key one in our society. Did Michael Portillo's or John Major's office "forget" the anniversary of the Somme? Are people who say they were sexually abused as children remembering real events, or misinterpreting others? Are eyewitnesses who give different descriptions of the same event lying? If we were all blessed with perfect memories, some say, we could know for sure.

Others contend that we remember everything perfectly: it's all "in there", and the only problem is getting it out. This camp tends to contain strong believers in the idea of "recovered memories", where adults' repressed recollections of horrific events in childhood can be pulled back to the surface intact.

But as John Kotre points out, in this beautifully guided tour through the landscape of our minds, we all forget. We have to: a perfect memory would be a curse. He cites the case of a young Russian newspaper reporter called Shereshevskii, who could retain lists of words, and recall them perfectly forwards and backwards, for years. But he could not forget anything, and so those lists sat in his mind, cluttering it; and he could not form abstractions from the groups of objects: everything was discrete, separate. "By the end of his life, all he could do was travel from town to town demonstrating his peculiar talent for memorising lists of words," writes Kotre.

So we have to forget some things, to be able to remember others. He explains how, as children learn language, they develop "scripts" for their days. This helps them know what to expect (and hence overlook, for the purposes of memory). Any parent will know that a child accustomed to an evening routine of dinner-bath-bedtime becomes enormously upset if given a bath before dinner. It doesn't fit the script: they fear dinner will not come.

But as also becomes clear, more complex versions of such scripts are vital to forming our personalities, and we misremember events in order to make them fit our self-perception. How many times have you heard people say things about their youth like "I was always picked last for sports" or "My father never gave me any encouragement"? Always? Never? Such absolute terms cannot be true. But similar misrepresentations of the past, and the present ("The boss never notices me") inform our personalities and guide our decisions. Memory has to be fallible to work. Thus "recovered" childhood memories of sexual abuse may be wrong - but may be correct, too. There is simply no hard and fast rule.

Thankfully, Kotre - professor of psychology at the University of Michigan- Dearborn - keeps his writing jargon-free, producing something like a user's guide to memory. But he has another purpose: the book is his tribute to his father, who has Alzheimer's disease, and so has no coherent memory from day to day of his son, his wife, his family, himself.

The personal touches that are sprinkled through the book could have turned into episodes of pure schmaltz, but Kotre has a sure, gentle touch. He recalls days spent fishing together; he recalls the company softball game where his father wowed the crowd. Kotre recalls all the details - but then admits he is unsure if they are correct. But no matter: the anecdote has done its work, of fixing his father's life in his memory.

Kotre clearly has a mission - to purge himself of guilt about neglecting his father, in favour of his own career. (The "white gloves" of the title recall how his grandfather had to abandon becoming a professional clarinet player; he wore the gloves to play). But while fulfilling that end, he provides us with a mirror in which we also gaze at our own relationship with our parents and our lives. What is your own earliest memory? What is the earliest memory that you think best defines your personality? Which best defines your relationship with your parents? Kotre throws the questions up to help to comprehend the process of memory. But in doing that, he helps us to begin to understand ourselves.