The Invisible Gorilla Strikes Again

TLDR

Inattentional blindness causes people to miss unexpected salient events while engaged in other tasks, and prior demonstrations have used naive observers in unfamiliar tasks. The study investigates whether expert radiologists, who have honed their ability to detect small abnormalities, are also susceptible to inattentional blindness. Twenty‑four radiologists performed a familiar lung‑nodule detection task in which a gorilla, 48 times the size of an average nodule, was inserted in the final case. Eighty‑three percent of the radiologists missed the gorilla, and eye tracking revealed that most who missed it looked directly at its location, demonstrating that even experts are vulnerable to inattentional blindness.

Abstract

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.