"They Have Eyes but Cannot See..."

“They have eyes but cannot see…” goes that famous saying. Except the issue isn’t with the eyes… If you don’t believe me, take this famous “selective attention test” (it takes less than 90 seconds). Believe it or not, half the people miss it!

 

And no, there’s no discernible pattern to who spots v/s misses it, say the folks who framed that test in The Invisible Gorilla. Not by age, gender, profession, IQ… anywhere you conduct the test, about half the people miss it. Almost unbelievably, they say:

“We truly are arguing that directing our eyes at something does not guarantee we will consciously see it.”

How can anyone possibly say, let alone prove, such a ridiculous statement? Aha, another scientist ran the gorilla experiment using his eye tracker and found that those who spotted and those missed it, both spent “a full second looking right at it”! The brain is apparently very good at filtering stuff, resulting in the illusion of attention (“we experience less of our visual world than we think we do”).

 

This has many practical consequences. A while back, there was an idea that projecting the flight information onto (part of) the plane’s front windows would ensure the pilots were able to see both the flight information and, er, anything else in their flight path simultaneously. Makes sense, right?

 

You might have guessed what flight simulator trials showed. Pilots using the new projection tech missed another “(simulated) plane on the runway” just as often as pilots who used the old system! Why are we missing those gorillas and planes?

 

One, if it’s not something we expect, we don’t register it (plane, gorilla, whatever). Two, it matters how much of our attention is “free” at that instant. If we’re doing something taxing (like counting basketball passes, or landing a plane), the brain has less processing power left for registering other stuff.

 

The second point incidentally explains why hands-free headsets while driving don’t help much. The issue isn’t with our hands, it’s that the total attention we can summon is limited. A phone call, hands-free or not, uses up part of our attention leaving less of it (attention) for driving the car. It also explains why doctors who are scanning a medical image for, say, tumours, can miss other seemingly obvious stuff (like a guidewire left inside the patient during an earlier surgery). In the doctors’ case, both points apply: they don’t expect to see guidewires inside patients, and they’re concentrating hard to spot a tumour.

 

You might be wondering:

“If this illusion of attention is so pervasive, how has our species survived to write about it? Why weren’t our would-be ancestors all eaten by unnoticed predators?”

Great questions. And the answer is that it is only in modern times that we have more and more attention-demanding situations. Also, the time to react has reduced with our technological advances:

“When you are walking, a delay of a few seconds in noticing an unexpected event is likely inconsequential.”

That’s not true if you’re driving, where a split-second delay could be fatal.

 

Worst of all? Since, by definition, we don’t even know of all those instances of attentional blindness (we don’t know what didn’t register), we have very little feedback telling us of the problem! How then can we improve on that front? Sadly, there’s no answer to this. The best we can do for now is to be aware of this limitation.