(Literally) blind experts

An American friend drew my attention recently to a paper published last year and entitled The Invisible Gorilla Strikes Again: Sustained Inattentional Blindness in Expert Observers. It is the report of a study in which experts failed to detect an unexpected occurrence (gorilla) in their area of expertise even when viewing it directly.

This phenomenon, known for a long time and, to my knowledge, first described in a paper published in 1999 by Simons andChabris, is known as inattentional blindness. In the past, it has been demonstrated with naïve subjects in unfamiliar tasks. The authors of the above study asked: does inattentional blindness also occur frequently among experts?

A very interesting and highly relevant question!

To study this, they asked 24 radiologists (hence experts) to screen CT (Computed Tomography) scans of lungs for nodules. The radiologists ranged in age from 28 – 70 years; hence some must have had very considerable experience. Their eye movements were tracked as they viewed the scans. But embedded in the scans was a gorilla which was some 48 times the size of the average lung nodule that the radiologists were searching for; moreover, it was positioned close to a nodule.

20 of the 24 experts did not report seeing the gorilla and eye tracking revealed that, of the 20 radiologists who did not report seeing the gorilla, 12 had looked directly at where the gorilla was located.

The authors conclude that, “This is a clear illustration that radiologists, though they are expert searchers, are not immune to the effects of IB [inattentional blindness] even when searching medical images within their domain of expertise”. They add, “Presumably, they would have done much better at detecting the gorilla had they been told to be prepared for such a target…perhaps a smaller gorilla would have been more frequently detected because it would have been more closely matched the size of the lung modules” [sic].

A sobering thought!

I imagine that, on the whole, radiologists do end up detecting the nodules, even if they are apparently often not able to detect something that is blindingly obvious (if I may use the phrase in this context).

But just think of experts in other domains, say economics, and above all of expert politicians of all stripes and in all countries. Thinking about them, one cannot help but suppose that they, too, must suffer from inattentional blindness, but this time of a more cognitive variety.

In fact, I am increasingly inclined to believe that many of today’s problems are due to the inattentional blindness of politicians to the continual and rapid and huge changes occurring (and here the size of the gorilla compared to the lung nodules comes to mind). I am increasingly led to believe that politicians just do not have their ears to the ground and, in many instances, are – because of this inattentional blindness - way behind public opinion on a great many issues. Hence they are not up to date experts.

Perhaps this puts the inattentional blindness of radiologists to huge gorillas embedded in the scans they are examining in perspective. 

Help...wine & cheese experts

About thirty years ago, some wine experts in France decreed that red wines should be chilled before being served. I was idiotic enough then to believe them and so chilled my red wine …but only once or twice. I rapidly came to the conclusion that I prefer my clarets at room temperature and have never been tempted back since.

Now, in an article published last week in The Daily Telegraph, another group of experts are reported to have patronizingly told us that we have all been fooled for years, that we must really accompany cheese with white wine, not red wine since the reds dominate all but the most robust cheeses, according to them. And of course, we must continue to serve white, never red, with fish.

All this is of course stuff and nonsense. The combination of wine and cheese that go best together are the wines and the cheeses which you like, ones which give you pleasure. I have always preferred my fish with a good claret and will continue to do so. I have always preferred my cheese with a good claret and will continue to do so. I agree more with Dr. Johnson, no wine expert he, when he said that “a fish must swim three times, once in the sea, once in butter, and once in a good bottle of claret”!

No doubt, as with the silly ideas about chilling red wine that the experts pushed some thirty years ago, they will sooner or later be pushing the idea that cheeses are best accompanied by red wine after all. And recall all this fuss about nouvelle cuisine some years ago, much of it extremely dreary. In fact there is a hilarious accompanying article in the same issue of The Daily Telegraph which pokes good fun at a seemingly new brand of nouvelle cuisine restaurant, which has opened in London.

Experts can peddle their silly views only when we lack confidence in our own tastes and in our own judgment. Why we do so is itself a very interesting psychological and neurobiological problem, as is the problem of why some combinations are judged better than others and why, in spite of our better judgments, we defer to the dubious authority of experts.

Which brings me to an interesting puzzle: why is it that, in England, we have the somewhat barbaric habit of serving cheese after dessert (have any experts commented on this?). Well, I have found out the reason, or one reason. I don’t know how true it is, but it is not implausible. The French have cheese pour faire chanter le vin [to make the wine sing], before moving on to the dessert accompanied by dessert wines, which ends the formal dinner. Apparently, in England quite some time ago, there was an anxiety on the part of men to end the formal dinner as quickly as possible so that the women could retire [or be made to retire] to a separate room, and the men could continue with refined binge drinking and men talk. And since dessert ends the formal dinner in both cultures, all they had to do was swap the cheese and the dessert around. And the habit has lingered on.