The Invisible Gorilla / Selective Attention Test Aim D.J Simons and C.F. Chabris of Harvard University wanted to nd out if people only see what they are paying attention to, and therefore created a selective attention test. Procedure The test was carried out with 228 participants. Participants were asked to watch a video in which six people were playing with an orange basketball. They were asked to count the number of times the ball was thrown, bounced or passed between those people wearing white T-shirts, of which there were three. Between 44 and 48 seconds into the video, either a woman carrying an umbrella, or a man dressed as a gorilla walked from one side of the screen to the other, over a period of five seconds. When the video ended, participants were asked to complete a questionnaire, which included the question of whether they had seen anything unusual or not. Results 50 percent of the participants said that they had noticed the woman with the umbrella or the man in the gorilla suit. This result suggests that inattention blindness does exist, in that when a person is focused on one thing, they may not see something else, even if it is very obviously there.
