20 2G M Wednesday August 12 2020 | the times

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Are you feeling ill? The computer willsee you now. And just like a humandoctor this medical app will use “im-agination” when making a diagnosis.

The result is a program that candiagnose illness with greater accura-cy than a GP — achieved thanks to anapproach that lets it think like a GP.

In 1,671 test cases the program,from the British healthcare companyBabylon Health working with col-leagues at UCL, correctly diagnoseda disease 77 per cent of the time, com-pared with 71 per cent by doctors.

But the most significant achieve-ment, outlined in the journal NatureCommunications, was not its accura-cy, but the way it made its decisions.

Conventional artificial intelligencehas progressed by applying more andmore computer power to look forcorrelations. This has producedprograms that can outclass people atradiography, mammography andeven in previously impregnable are-nas such as the games chess and Go.

Some scientists have worried thatthere is a flaw in the approach that

Virtual GP that beats thedoctor to right diagnosis

will ultimately limit it: computers seecorrelation, they don’t see causation.

Judea Pearl, an artificial intelli-gence pioneer at the University ofCalifornia Los Angeles, calls this theproblem of “why”. People know that adisease causes symptoms, computersknow that there are symptomspeople have when they also have adisease. The difference is crucial.

“This is about the soul of datascience,” Professor Pearl, who wasnot involved in the research, said. AIhas found the “low hanging fruit”, butexpecting true intelligence to emergeis, he says, a little like “simulating evo-lution and expecting to get Einsteinfrom an amoeba. It takes too long”.

Consider a computer programtrained to look for the cause of flood-ing on roads. It might see that whenstreets are waterlogged lots of peoplealso use umbrellas, and conclude thatumbrellas cause floods. In fact bothhave a deeper cause: rain.

Similarly, imagine an elderly smok-er with chest pain, nausea andfatigue. Many people with thosesymptoms have emphysema, and acomputer might conclude that this

was the cause. A GP would know it isangina. Lots of people have emphyse-ma and those symptoms not becauseone causes the other but becauseboth have a deeper cause: smoking.

To train a computer not to fall intothis trap, to help it spot causation,involves teaching it to consider“counterfactuals”. Would there stillbe floods without umbrellas? What ifthe patient did not have emphysema?Would the symptoms go away?

Using medical modelling the com-puter is able to “imagine” what wouldhappen if a disease was magicallycured. Did the symptoms go too?

“If the symptoms did go away thenwe’d know the thing that generatedthem was the disease,” JonathanRichens, the lead author, said. “In thecase of emphysema, they won’t goaway because it doesn’t make youhave chest pain or dizziness.”

Professor Pearl said that it wasearly days but he was “very hopefulthey have broken a barrier here.”

“I’m going to use it as a warning tomachine learning enthusiasts in theUS — you’re going to be made obso-lete by companies in the UK.”

Tom Whipple Science Editor

Boys whose mothers sufferdepression during pregnancy aremore likely to be aggressive andhyperactive as they are about to startschool, a study has found.

Brain scans showed that they hadaltered connections between theparts of the brain that affect emotion.Their mothers also reported childbehavioural problems.

One in five women experience de-pressive symptoms during pregnancy.

Researchers asked women a seriesof questions to check for depressivesymptoms three times during their

Prenatal depression affects boys’ brains pregnancy and after their babieswere born. Once the children wereaged four they were given an MRIscan to assess their white matter con-nections between brain regions thatare involved in emotional processing.Their parents also completed asurvey asking about behaviour.

The research, by the University ofCalgary, Canada, and two medicalresearch institutes and published inthe Journal of Neuroscience, foundthat boys whose mothers experi-enced prenatal depression were morelikely to show altered brain connec-tivity which could affect theregulation of their emotional state

and was associated with increasedaggression and hyperactivity.

The correlation between higherlevels of depressive symptoms amongmothers during pregnancy and dis-ruptive behaviour was less strongamong girls.

The study involved 54 mothers andtheir children, of whom 30 were boys.Given its small scale some cautionshould be attached its findings.

Prenatal depression has beenlinked previously to behaviouralproblems in children but the latestresearch highlights weakened brainconnections as an explanation forhow this happens.

Greg Hurst Social Affairs Editor

TONY FRANCIS

Harry Dunn’s family seekremote trial

The government has been urged toconsider a trial via videolink for thewife of an American diplomat whofled after the death of Harry Dunn.

Mr Dunn, a 19-year-old motorcy-clist, was killed last August in a head-on collision with Anne Sacoolas’s carshortly after she turned out of RAFCroughton in Northamptonshire.

Mrs Sacoolas, 42, left the country,claiming diplomatic immunity. Shewas charged with causing death bydangerous driving but the UnitedStates rejected an extradition request.

Now Mr Dunn’s local MP, AndreaLeadsom, has asked for a remote trial.In a letter to the home secretary,foreign secretary, attorney generaland crown prosecution service, shesaid Mrs Sacoolas could remain onUS soil. “Should there be a custodialsentence, she could serve it in the US.”

Mr Dunn’s mother, CharlotteCharles, said that she wanted justicefor her son and that a trial via video-link could be a step towards closure.

Neil JohnstonMidlands Correspondent

In a spin An anti-clockwise roundabout appeared in Berkhamsted, Hertfordshire, yesterday. The error was fixed hours later

This Country team to make period comedy

The siblings behind the BBC mocku-mentary This Country have revealedtheir next project: a period comedy.

Daisy May Cooper, 34 and CharlieCooper, 31, endeared themselves tomillions as Kerry and Kurtan Muck-lowe, a bumbling pair of Cotswoldsne’er-do-wells, in the Bafta-winningshow. They are swapping village lifefor a historical romp after the thirdand final series of This Country wasbroadcast earlier this year.

“Charlie and I have started writingour new thing, which is very, very dif-ferent,” Daisy May told the WhiteWine Question Time podcast, hostedby Kate Thornton. “It’s a period thing. . . but it’s funny.

“For This Country, we couldn’twrite for ‘names’, like for famousactors, it would have to be [for]unknowns. So this is actually quitefunny to have an actor in mind and beable to write a part for them specific-ally. It’s very, very early days but we’rereally enjoying it.”

Matthew Moore Media Correspondent

The Times, UK

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