AGE IS what we all do, but as Paul Auster notes in the opening sentence of his new memoir, "You think it will never happen to you, that it cannot happen to you, that you are the only person in the world to whom none of these things will ever happen, and then, one by one, they all begin to happen to you in the same way they happen to everyone else."

Time is running out for Auster – one of America's most celebrated writers – so he has decided the moment has come to put aside his fiction and try to examine what it has felt like to live inside his body from the first day he can remember being alive until the one when he embarks on Winter Journal, his "catalogue of sensory data. What one might call a phenomenology of breathing."

On a snowy January day, one month before his 64th birthday in February, 2011, New Jersey-born Auster began writing Winter Journal, a plangent but humorous book that he tells me "just poured out" of him, despite the fact that he had to dig deep into his memory of his memories. It is a memoir like no other I have ever read, giving new meaning to the phrase body of work.

"I know what you mean," concedes Auster, speaking from the beautiful, book-lined, art-filled Brooklyn home he shares with his second wife of 30 years, the acclaimed writer Siri Hustvedt, his first and most valued reader. "I've never read another book like it either. I believe it is the first time any writer has told the story of their life through their body. I have no idea why I wanted to write the book; I never know why I want to write any book. This idea just felt very compelling to me, so I went with it and I have tried to be honest in it."

Winter Journal tells how our ageing, decaying bodies are maps of our lives, so the novelist, poet, screenwriter, film director, translator, essayist, memoirist – Auster made his name with his mysterious debut memoir The Invention Of Solitude (1982), about his late father, followed by two other autobiographical works, The Red Notebook (1995) and Hand To Mouth (1997) – turns cartographer, carefully recording his physical terrain, often in forensic detail.

He chronicles the inventory of scars scribbled on his face; childhood accidents; the dislocated shoulder; the stinging attack by hornets; his phantom heart attack and other curious psychosomatic ailments; his "years of phallic obsession" when he was "a willing slave of Eros", and the ensuing deliriums and mad surges of desire; the blood clot in his leg; the monstrous panic attacks that ripped through his body and threw him to the floor; the near-fatal car crash in which he feared he'd killed his wife and daughter; and, most poignantly, the sudden death in 2002 of his marvellously resilient mother, Queenie, "a sumptuously decked out charmer ... who dazzled the world in public."

This long section is by far the best part of Winter Journal, in which he also reveals on the penultimate page that he still dreams about his father, Samuel, although it's 35 years since he died. He talks to his father in those dreams. Once he wakes up, he can't recall a single word either one of them has said.

"I wanted to write about my mother's life because my life and my own body began in my mother's body, so I wanted to write about her death, too, which was unbearable, although I didn't cry. I do cry in life every once in a while – more over books and films than real events, however. Something in me shuts down in the face of death, which is probably why my body broke down after her death and I had a panic attack when I absolutely thought I was dying. My limbs turned to stone; it was the most terrifying moment of my life."

Neither of his parents is named in the book, nor is his "sublimely beautiful" 57-year-old wife, Siri ("the One ... the grand love") and their singer-songwriter daughter, Sophie, 25, "whose parents are bursting with pride because she is so talented and so lovely," he enthuses to me. His first wife, the brilliant short-story writer Lydia Davis, and their son, Daniel, 35, are unnamed shadowy presences, too. This, says Auster when I ask him about it, is because the book is not about his children at all. "Sophie, my daughter, is hardly in the book, because it's all about my physical being. Every entry is about my body: autobiographical fragments arranged in a kind of fugue-like way rather like a musical composition, say."

So while Auster sometimes appears to offer too much information – "the enormous boil that sprouted on the left cheek of your ass" which prevented him from sitting for a week; the one and only time he peed his pants; and the pleasures of scratching an itch, sneezing and burping and farting – he withholds a great deal in his meditations on mortality. Perhaps because he has chosen to relate this book using the tricky second person "you" – in The Invention Of Solitude, he's "A" – which is rare in literature. Nonetheless, it gives his writing immediacy and power.

"I didn't want to use the first person, the traditional 'I' of memoir. It seemed too egocentric, too hermetic," he explains, adding that obviously the second person means that the reader can also identify with his musings on what it feels like to be no longer young in a way that the distancing third person would not have allowed.

"We all have bodies. We all share the fact that our bodies fail us and hurt us and cause us pleasure and pain – these are the conditions of life," he says, so the use of "you" means that he's directly addressing you, the reader. "I really wanted to discuss the fact that the body is the site of events, written by an invisible hand, that have often been expunged from history. Your story begins in your body, and everything will end in the body as well."

The tall, greying, gothically handsome Auster's body is no temple, however. "Far from it!" he exclaims, with a nicotine-scarred laugh that rapidly guns up into a hacking smoker's cough. He admits that he smokes too much (chains of little cigars) and drinks too much ("frequent glasses of wine").

His wife, he confesses, worries about him, especially about his smoking and drinking. Yet he forges on with his "vile habits". Alcohol and tobacco serve as crutches to keep his crippled self upright and moving through the world, he believes. His wife calls it self-medication.

There is no doubt, Auster writes, that he's a flawed and wounded person, a man who has carried a wound in him from the very beginning. Why else, he asks, would he have spent the whole of his adult life bleeding words onto a page? (Strangely, in one of several interviews I have conducted with his wife, she too has spoken of the fact that she can't remember a time when she did not carry around inside her a sensation of being "wounded".)

When I put this to Auster, he replies: "I've always believed that artists are damaged people in one way or another, that we need to do what we do in order to hold ourselves together. Most people don't feel they have to do this kind of thing – it's not pressing on them."

It was his maternal grandmother, whose death he also writes about in Winter Journal, who gave him his first experience of literature: a set of Robert Louis Stevenson for, he thinks, his eighth birthday. They were too hard for him so he read them when he was maybe 10. He loved A Child's Garden Of Verses – "the idea of a grown man projecting himself into the mind of a child was my first experience of what literature was, that you're actually thrusting yourself into another consciousness."

He's thrusting himself into yet another consciousness with his next book, another memoir, only this time he'll be mapping his mind. "It's the story of my inner life and dawning consciousness and early intellectual life – I recall writing a poem to great joy when I was about nine-years-old, for instance. One of the worst poems ever written! So, yes, I am still sitting alone in a room, examining the inside of my head."

He feels remarkably fit for 65 – "it's official, I'm a senior citizen!" – but wants to pass on a dear friend's jokey wisdom. "She's in her eighties. She says, 'Once you're over 60, if you don't wake every morning with some aches and pains, you're dead.'" Inevitably, he murmurs, he wonders how many mornings are left. After all, as the final line of his book has it: "You have entered the winter of your life."

Winter Journal by Paul Auster is published by Faber and Faber, £17.99