The trouble with brain scans

There's a worrying problem with the way neuroscience made the headlines at the end of last month. Scientists at the University of California, Berkeley, had looked at the electrical signals generated in the brains of patients listening to speech. From those signals, they were able to infer some of the words being heard. Such work may one day help us listen to the thoughts of comatose or locked-in patients. So what's the problem? It will add to the unfounded faith in scientists' ability to read minds - a ticking time bomb for the legal system.

Research has shown that people are much more likely to believe a statement prefixed with the phrase "Brain scans indicate . . ." That has been true even when the statements were obviously scientifically flawed. It was also true for neuroscience students who should have known much better.

Things are made even worse with functional magnetic resonance imaging (fMRI) scans, pretty pictures that look like they contain much more data than they actually do. These differentiate the relative amounts of blood flow in the brain. The differences are generally displayed on "false-colour" pictures: like a Tube map, the colours are arbitrary and are used just for contrast; they are not an absolute measure of anything. But they look ever so significant.

That would explain why, in 2009, a defence team in the US tried to use fMRI scans to convince a jury to reduce the sentence of a convicted rapist and murderer. Brian Dugan had confessed to the 1983 abduction, rape and murder of a ten-year-old, Jeanine Nicarico. He was already serving a life sentence for two other murders and faced the death penalty for this crime. With the aid of Kent Kiehl, an expert on psychopathy at the University of New Mexico, the defence team showed the jury scientific evidence derived from fMRI scans. The evidence, according to the defence, showed Dugan to be a psychopath.

The jury eventually rejected the evidence and sentenced him to death. But the jurors' hesitation - they stayed out for five hours - provided a moral victory for the defence and gave grounds for appeal against the sentence.

It's worth pointing out to anyone who might find himself on a jury that whether you can infer anything solid from one person's fMRI scan is so far entirely unproven. All tests of fMRI have been carried out on groups of people; the indicative calibration maps of relative blood flow are an average over many individuals.

False memories

What's more, all fMRI calibration studies for brain-reading so far involve hugely artificial situations - students being paid to sit in scanners and tell banal lies, for example. Applying inferences from that kind of research to real-world situations is simply not justifiable. The technology can't distinguish between wishes or desires and what happened. If you imagine you have done something - whether or not you did it - the scan will see it: it cannot distinguish between real and false memories.

The biggest responsibility for the appliance of science here will lie not with jurors but with the neuroscientists who get involved in legal proceedings. They will face pressure to overstate the permissible conclusions.

Having carried out the fMRI scans on Dugan, Kiehl told the BBC that Dugan "struggles to try to understand why people even care about what he did". However, the defence attorney handling the appeal told the Chicago Tribune that Dugan had "expressed his sorrow and his remorse for what he had done".

The truth is out there but not everybody wants to expose it - and endorsing half-baked science won't help.

Michael Brooks's "Free Radicals: the Secret Anarchy of Science" is published by Profile Books (£12.99 paperback)

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

Show Hide image

Why the philosophy of people-rating app Peeple is fundamentally flawed

The app claims that “character is destiny”, and that we should be constantly judged based on our past interactions with others. But do we really believe that? 

Yesterday, you were probably one of the millions around the world who recoiled from their screen in blank-eyed horror at the news: Peeple, an app to be launched in November, will let others rate you, publicly, on the internet, and there's nothing you can do about it. You can't opt out, and you don't need to join in order to be rated on a scale of one to five by colleagues, friends, and romantic partners. That boy whose girlfriend you stole? He can review you. The boss you swore at as you quit? Her, too. Those people in your life who think you're just a bit average? Expect a lukewarm three stars from them.

Of all the online rage at the app's announcement, perhaps the most was directed at the fact that you can't remove your own profile. Other users need only submit your mobile number and name to create your page, and you have no control about who posts on there. Reviews of two stars or less are invisible to the public for 48 hours, and you have the chance to review them and try to "work it out" with the rater. Once that time is up, though, the negative reviews appear for all to see. You can comment on them to defend your corner, but unless they break the app's rules, you can't delete them.

There are all kinds of problems with Peeple's premise. Despite its founders' promises that bullying and harassment won't be tolerated (helped slightly by the fact that users must be over 21 and use their full name and Facebook profile to comment), it seems impossible that they'll be able to moderate this effectively. And as we've learned from sites like TripAdvisor or Yelp, the majority of reviews are from those seeking to boost the company's reputation, rivals, or angry customers - it's rare to see one that's balanced and helpful.

Yet the biggest flaw of all is the assumption that public rating and shaming has a place, or is even acceptable, in our society. There's something fundamentally broken in the app's presmise, which is summarised in its tagline, "character is destiny".  As western society has moved on from earlier ages where people were fundamentally changed in the eyes of the law and public into "criminals" by virtue of their deeds, or a time where a woman was utterly defined by her sexual acts, we've ceased to accept this as truth. The app's whole set-up assumes that someone who has offended a co-worker is likely to do it again, or a positive review from a partner makes it likely you'll enjoy a good relationship with them. As a society, we accept that some violent criminals are likely to re-offend, but we also see the value of rehabilitation, and can accept that people make mistakes they're unlikely to repeat. 

The dark side of social media is that it moves us backwards on this front. It allows permanent imprints of our online lives to be seen by everyone, to the extent where they seem to represent us. Victims of cyberbullying terrified that naked photos of them will be released, or people who make public gaffes on social media, become reduced to and defined by single acts. The mental health deterioration (and sometimes  suicide) that follows these shamings hints at how unnatural it is for single actions to change lives in such disproportionate ways. 

Jon Ronson, author of So you've been publicly shamed, which cleverly links the current culture of internet shaming with a legal past where criminals were shamed indefinitely as criminals for a single illegal act, seems chilled by the prospect of Peeple:

As one review of Ronson's book noted:

As Ronson makes patently clear, all these people’s punishments by far outweighed the gravity of their so-called crimes. In fact, having researched the history of public shaming in America in the Massachusetts Archives, he can only conclude that Lehrer, for one, was humiliated to a degree that would have been thought excessive even in the 18th century, the Puritans of New England having seemingly worked out that to ruin a person in front of his fellows is also to refuse him a second chance in life.

As Ronson explores in his book, extreme public shaming doesn't make us better people, or encourage us not to repeat offend: it shuts us down and exiles us from society in a way that benefits no one. (This makes Peeple's URL – – seem grimly ironic). What Ronson calls "chronic shame" occurs when our regretted actions harden into something far greater, something we allow to become part of ourselves. As Gershen Kaufman, a scholar of shame, notes:  "Shame is the most disturbing experience individuals ever have about themselves; no other emotion feels more deeply disturbing because in the moment of shame the self feels wounded from within."

We also shouldn't be forever defined by a clutch of "good" actions, or people who see some benefit in leaving us gushing reviews. Those who measure their worth through social media come to rely on the endorphins sparked by small online interactions and boosts to their confidence, at the expense of the more slow-burning satisfaction of real life. A single person's thoughts about us are relatively inconsequential, whether positive or negative - but they're given far greater weight on the internet  by virtue of their permanence and publicity.

In Mary Gordon's novella The Rest of Life, a character wishes that someone had told her earlier that "the world is large and will absorb the errors you innocently make". If we're to avoid tearing each other to pieces, we need to make sure that this remains the case. 

Barbara Speed is a technology and digital culture writer at the New Statesman and a staff writer at CityMetric.