In a famous psychology experiment, participants watching a video of people passing a basketball around while moving missed a remarkable sight: Midway through the video, someone wearing a gorilla suit strolls through the exercise, pauses to beat his chest, and moves on. The key was that participants were asked to count the number of passes made by players wearing white shirts, and the focus on one activity induced a kind of blindness to the extraordinary visitor.
A new study shows that “inattentional deafness” exists, too. Forty-five people listened to a 3D, stereo recording, lasting just over a minute, of two men and two women independently discussing preparations for a party. Half the participants were instructed to listen closely to the men’s conversation, half to the women’s.
Halfway through the recording, a man moves through the audio landscape saying “I’m a gorilla. I’m a gorilla,” before exiting. This lasts 19 seconds. Afterward, when asked if they heard anything odd, 90% of the participants who were attending to the male voices mentioned the gorilla-man — but only 30% of the participants focusing on the female voices did….