Yep, you read that headline right . . . most radiologists don’t notice a gorilla in a CT scan.
Now, since I’ve had a partially collapsed lung for quite some time, I’ve seen more than my share of CT scans of the lung and it’s absolutely fascinating to watch my specialist doctor go through the sucker and make heads or tales out of what to me is a mass of moving blob images. My doctor is very good so I trust his opinion.
However, here’s a bit of brand spankin’ new research that my critical thinking and social influence students may appreciate.
As Sarah Kliff reports over at the Washington Post . . .
It is, perhaps, a movie instantly familiar to anyone who has taken an introductory psychology class: The gorilla who walks through a group of kids passing a basketball between them and, for many, goes unnoticed.
The invisible gorilla experiment, as its come to be known, is meant to demonstrate inattentional blindness. When asked to focus on one particular factor—in this case, how many times students pass a ball between each other—other stimuli will go completely unnoticed. In this case, that’s the man in a gorilla suit.
If you’re not familiar with this experiment, there’s a discussion and video on a previous entry at https://briandavidphillips.net/2011/03/28/selective-attention/.
It turns out missing the gorilla isn’t just true for psychology students: A recent study found that a vast majority of radiologists failed to notice a very large gorilla that researchers added to a medical scan.
Trafton Drew, Melissa L. H. Vo and Jeremy M. Wolfe had 24 radiologists look at CT scans of lungs, scanning them lung nodules, which could be cancerous. Each CT scan had an average of 10 nodules and the radiologists were asked to click on them. The last of the five CT scans had something unexpected turn up on the lung: A gorilla. You can see him in the image above (click on him to see the full size version), waving his arms at the top of the right lung (although, to be fair, the version of the image used in the experiment is NOT colored for easy viewing).
Most radiologists, however, did not see him. When asked “Did you see a gorilla on the final trial?” 20 of the 24 radiologists tested said they did not. It wasn’t for lack of looking. As the researchers write, in a forthcoming paper in Psychological Science, “eye-tracking revealed that, of the 20 radiologists who did not report the gorilla, 12 looked directly at the gorilla’s location when it was visible.”
On the more positive side, the radiologists did perform better than the untrained eye: When the researchers ran a group of non-doctors through the experiment, no one noticed the gorilla on the scan.
How much does this matter for radiologists? They’re never, after all, going to encounter a gorilla on a real scan from a patient. It does, however, suggest that specialists could easily miss other red flags when they’re on the search for one specific indicator.
“Why do radiologists sometimes fail to detect such large anomalies? Of course, as is critical in all IB [inattentional blindness] demonstrations, the radiologists were not looking for this unexpected stimulus,” they write. Even experts “operating in their domain of expertise, are vulnerable to inattentional blindness.”
This is a big deal in that selective attention or inattentional blindness can mean we miss important elements of an argument or social context because we are focused on minutia . . . yes, we can indeed miss the forest because of the trees and that’s a big thing to understand.
Interested in other sorts of social psychology of this sort? Check out the concept of Change Blindness which is related to Inattentional Blindness or Selective Attention . . . here’s a post with videos at https://briandavidphillips.net/2011/03/28/change-blindness/. Yes, it’s real . . . using these principles an entirely different person is actually substituted into the conversation or scenario and many people don’t even notice (although, in fairness, most folks would at least feel a bit disconcerted via cognitive dissonance from the Jackass switch). There are a few more humorous videos employing the mechanics of change blindness here and here. By the way, students in my critical theory and communication courses at the university as well as those in the HPTI program might consider some of these videos as inspiration for their own experimental design videos for their respective classes.
Speaking of social influence, you can learn a whole slew of new techniques by checking out our video training programs in social influence, waking hypnosis, and more which are in general release.
If you’re in Taipei and interested in hypnosis, check the services page linked to in the top left sidebar. Not in Taipei? Check the store for recordings in the same menu area as well as links to lots and lots of info and goodies. Of course, browsing this site will bring you to a digital ton of positive resources on a wide variety of topics as well.
All the best,
Brian
www.BrianDavidPhillips.net
