As an amateur magician, I am often intrigued by the world of psychology, an area where science and the arts combine to create some pretty weird effects. Magicians have honed the art of directing attention (misdirection) over the centuries, to the delight of audiences. Among the ‘mind glitches’ they exploit is ‘change blindness,’ where part of an image is changed but the observer doesn’t notice. A classic demonstration of this is to rapidly switch near-identical images with a split-second of blank screen between them. You’d think you’d see the change, but the blank screen trips you up. If you don’t know what to look for, you’ll probably miss it. There are hundreds of demonstrations online that show just how strong this effect is.1 Another type of change blindness is demonstrated by Richard Wiseman’s Amazing Colour Changing Card Trick2.
While some ‘tricks of the mind’ are now understood, there are others that will keep researchers busy for decades to come. One is ‘choice blindness,’ demonstrated by amateur magician (and full-time psychologist) Petter Johansson from Lund University in Sweden.3 His team showed participants two pairs of faces on cards and asked them to select the most attractive. Participants were then passed the image across the table and asked why they selected it. The participants were able to explain their selection: He has nice eyes; I like blondes; She’s got a great smile, etc... But here’s the kicker: Of the 15 selections made by each participant, three were switched using sleight of hand. They were given the card they had actually rejected. Only a quarter noticed.
Johansson found that participants’ answers were just as sincere and detailed when they were given the rejected face as when they were given the chosen one. They even highlighted aspects of the rejected face, for example earrings or a beard, that were absent from the selected photo as reasons for their selection. From this Johansson concludes that, whatever it was that made the participant select that particular face, ‘it wasn’t the earrings.’ As you might expect, when told about the real purpose of the experiment, the participants were shocked. Some refused to believe the researchers until they had seen the footage. Humans are hard-wired to regard their individual experience of the world as faultless, while treating those of others as highly suspicious.
Johansson’s research opens up some uncomfortable questions. What mechanism causes the participant to forget the details of a face they saw a few seconds earlier? More to the point, why do they then seek out reasons to justify a selection that they didn’t even make? This may, or may not be answered through further research.
More recently, Johansson has gone further down the ‘choice blindness’ rabbit hole. His team asked people in Sweden to take part in a short political survey, in which they were asked to tick boxes according to their views on taxes, healthcare, immigration and so on. While they did so, the researcher filled in a second form with answers that did not match the views expressed. The participant was then, as in the face card experiment, (sleight-of) handed a different set of views to the ones they had expressed moments ago. Right-wing responses were switched for more left-wing ones, and vice versa.
Somewhat alarmingly, when participants were asked to justify the ticks on ‘their’ sheets, they failed to recognise the change and even rationalised their ‘imposter’ viewpoints with solid arguments. Indeed, the more they explained themselves, the more convinced they became that they were simply elaborating on their original answers. Again, we view our own experience as reliable and view that of others as suspicious. The researchers’ mind trick is simply to present the participants with views that they themselves think are theirs.
So what next? Can a climate-change skeptic be converted into the next Greta Thunberg? Can a ‘cat person’ develop a sudden liking for dogs? Can a wood construction advocate come around to the benefits of cement and concrete? These examples seem far fetched, but then so do the conclusions of the political views experiment. The Ethics Board at Lund University must be busy!
While initially unsettling, Johansson points out that his research simply shows our preferences to be more malleable than we think. Now that we know this, we can take steps to avoid falling into its various pitfalls. We can start, he says, by not sweating the small stuff and being less critical when people change their minds. Beyond this, choice blindness shows that confirmation bias - where people rationalise evidence in support of their pre-existing viewpoint - can be circumvented. This could be very helpful when dealing with those of opposing views and, in a world full of Covid-19, political turmoil and an ongoing climate crisis, we need to communicate more effectively than ever before.
1. https://www.youtube.com/watch?v=bh_9XFzbWV8
2. https://www.youtube.com/watch?v=v3iPrBrGSJM
3. https://www.youtube.com/watch?v=wRqyw-EwgTk
4. https://www.youtube.com/watch?v=FWSxSQsspiQ&index=4&list=PLE3048008DAA29B0A
