As a radiologist, you develop a search pattern over years of practice and go through it. For example, I personally look at the lung parenchyma in almost quadrants. But, if someone just shows me a CT, I jump into the interesting part. That is the reason you should read scans in a relatively calm environment without distractions.
Most of the misses happen when you are distracted by a phone or something else, so your normal search pattern is disturbed. That is the reason you should not call the radiology department for a fast read on a scan.
Gorrilla is not a normal or abnormal structure you expect to see on a chest CT. This may make a blind spot for you.
I haven't read the study, but I did hear the NPR story. The story made it sound like they asked the radiologists to look for one thing and one thing only - cancerous nodules, and then had a "gotcha" moment when the radiologist didn't mention the gorilla.
Consider it in these terms: a pulmonologist comes to ask you about a chest CT. At the workstation, he explains that he's worried about lung cancer and asks your opinion about some nodules. You spend a few moments looking at the nodules, and perhaps a few more moments checking out the pertinent negatives/positives. After you share your thoughts, he then becomes annoyed that you didn't mention the aortic root dilation. He then considers this a "miss" and decides to right up a paper about how blind radiologists are.
I'm sure I'm missing some nuance of the study, but this sort of construct sets the radiologist up for failure. It's also not realistic or representative of normal practice.
Nonetheless, I thought the story painted radiologists in an overall favorable light. I don't think it's a bad thing if more people learn more about the concept of visual attention and its deficits. I think it will help radiologists the more people understand that anyone will occasionally - but reliably - not see something on a picture that is blatantly obvious to others or in hindsight. It doesn't matter if it's a radiologist at a viewbox, a security guard monitoring a surveillance video, or an analyst at the NSA going over satellite photographs. It's just how our brains are hardwired.