Reading between the lines: how Iris Murdoch's last book shows she was in grip of Alzheimer's

Iris Murdoch's last novel, Jackson's Dilemma , was a puzzle even to her nearest and dearest. So when scientists approached John Bayley, her husband, with a proposal to examine it for signs of Alzheimer's disease, he readily agreed.

Iris Murdoch's last novel, Jackson's Dilemma , was a puzzle even to her nearest and dearest. So when scientists approached John Bayley, her husband, with a proposal to examine it for signs of Alzheimer's disease, he readily agreed.

"I told them that I had felt all along that there was something different about [it], that it was moving but strange in many ways. I felt sure that [the researchers] would find something unusual in her writing," he said.

Today, a team from the Institute of Cognitive Neuroscience at University College London, publishes the results of a textual analysis of the novel - about the lives and love affairs of a group of friends - which was published just before Murdoch was diagnosed with Alzheimer's in 1995.

The experts say it shows a smaller vocabulary than her previous novels, which were noted for the richness of their language, suggesting she was in the grip of the "word-finding difficulty" characteristic of the earliest phase of Alzheimer's.

The finding could lead to the development of more sensitive tests for Alzheimer's, based on analysis of correspondence or diary entries, to detect the disease early.

As well as being a prolific novelist, Murdoch had a formidable intellect and began her career as a lecturer in philosophy, first at Cambridge University and later at Oxford. Her unconventional lifestyle and acerbic tongue kept her at the forefront of the literary scene. She won the Booker Prize in 1978 for The Sea, The Sea and was created a Dame in 1987 in recognition of her contribution to literary life, but reviewers greeted her last novel with disappointment.

A S Byatt said Jackson's Dilemma was akin to an Indian rope trick in which the characters "have no selves and therefore there is no story". Penelope Fitzgerald suggested that the economy of the writing made it appear that Murdoch had "let her fiction wear through". Hugo Barnacle described it as reading "like the work of a 13-year-old schoolgirl who doesn't get out enough".

Murdoch confessed she had suffered writer's block while trying to complete it - an early sign of the illness.

The researchers compared Jackson's Dilemma with two of her earlier novels - The Sea, The Sea , written when she was at the peak of her powers in the mid-1970s, and Under the Net , her first novel, published in 1954. They found that while the structure and grammar remained consistent, her vocabulary had dwindled and her language was simpler in her last novel.

The texts of the three novels were converted to digital format, which was analysed to show the frequency with which each word was used. The smallest vocabulary was in Jackson's Dilemma and the largest in The Sea, The Sea . The rate of introduction of new words was strikingly greater in the earlier works than in the last.

Peter Garrard of the Medical Research Council's cognition and brain sciences unit said: "Alzheimer's is known to disrupt the brain's semantic system, but this can happen subtly before anyone has the remotest suspicion of intellectual decline.

"Intriguingly, Murdoch experienced an intense and unfamiliar feeling of writer's block during this period. It would appear that the disease was already beginning to disrupt her cognitive abilities."

Murdoch was diagnosed with Alzheimer's at the age of 76. A brain scan in June 1997 showed shrinkage of the hippocampus, associated with memory, and a classic sign of Alzheimer's disease. The diagnosis was confirmed after her death in 1999.

Mr Bayley said: "Iris donated her brain to medical science to help in the search for a cure for Alzheimer's disease. We are still a long way off from that cure but every study that sheds light on how Alzheimer's develops will ultimately help scientists to diagnose and treat patients at the earliest possible stages of this disease."

Critics say many of the greatest works of fiction deliberately use a pared down vocabulary and the use of words alone cannot reveal the physical state of their creator. But Dr Garrard said that the change in Murdoch's use of language was as predicted for Alzheimer's.

"We knew what to expect. We didn't just trawl the novel for simplicity. The sentence structure remained complex, only the vocabulary changed, which is typical of Alzheimer's."

HOW HER PROSE CHANGED

The Sea, The Sea (1978)

The chagrin, the ferocious ambition which James, I am sure quite unconsciously, prompted in me was something which came about gradually and raged intermittently.

Jackson's Dilemma (1995)

Owen had laid out a little table with whisky and red wine and orange juice and ham sandwiches and olives and plums and cherry cake.

Peter Garrard comments: "The first sentence contains 24 words of 22 different sorts (ie, each word is used, on average 1.1 times). The second sentence contains 25 words of 20 different sorts (ie, each word is used, on average 1.25 times). These differences may not seem large, but when multiplied over the length of a large text they become significant.

"I have also found the frequency values for the words in each of the two samples - the number of times each word tends to be used in written English - indicating how common they are. The mean frequency for The Sea, The Sea is 75.6, and the mean frequency for Jackson's Dilemma is 111.2, illustrating the unusual vocabulary used in the first compared with the second."