Invisible gorillas I have known and loved

Seeing as how there are about 5 other things I'm supposed to be doing right now, I am instead cruising the abstracts for Psychological Science articles.

The Invisible Gorilla Strikes Again
Sustained Inattentional Blindness in Expert Observers
Psychological Science July 17, 2013

Trafton Drew
Melissa L.-H. Võ
Jeremy M. Wolfe

Researchers have shown that people often miss the occurrence of an unexpected yet salient event if they are engaged in a different task, a phenomenon known as inattentional blindness. However, demonstrations of inattentional blindness have typically involved naive observers engaged in an unfamiliar task. What about expert searchers who have spent years honing their ability to detect small abnormalities in specific types of images? We asked 24 radiologists to perform a familiar lung-nodule detection task. A gorilla, 48 times the size of the average nodule, was inserted in the last case that was presented. Eighty-three percent of the radiologists did not see the gorilla. Eye tracking revealed that the majority of those who missed the gorilla looked directly at its location. Thus, even expert searchers, operating in their domain of expertise, are vulnerable to inattentional blindness.

I'm going to have to tell my story about sitting on a subway with a knife pointed almost directly in my face (or my boyfriend's face, at any rate) & not noticing.

I did notice that my boyfriend (I was maybe 20-years old at the time) was looking anxious as all get out.

That, I noticed.

I also noticed the couple standing immediately beside him, arguing over something to do with an apartment they were going to. As I recall, they were ticked off at its resident--they agreed on that--but they seemed to disagree on what to do about it. So they were arguing.

Didn't see the knife one of them was brandishing.

Or the gorilla.