Review: Chabris, Simons, The Invisible Gorilla

Inattentional and change blindness are two fascinating phenomena that more people should be aware of. The Invisible Gorilla describes them as well as some other interesting and surprising psychological research.

This book has been out for over three years, and I’ve been meaning to write a review forever. What brought it back to my attention is a recent news story on the safety implications of voice-controlled systems in cars. Just because your hands are on the steering wheel and your eyes on the road doesn’t mean your attention is anywhere near.

Attention is a key element in our cognition, but it is only poorly understood. Christopher Chabris and Daniel Simons have done some of the ground-breaking work in this area, in particular about inattentional blindness and change blindness. Both phenomena have highly entertaining experiments at their basis.

The Selective Attention Test that the book gets its title from asks people to count the number of times one of two ball-playing teams passes the ball. After a minute, a guy in a gorilla suit walks through the scene. Most people are so focused on the task that they don’t see the gorilla. The Door Study is even more bizarre: an experimenter asks a stranger for directions in the street. Two workers appear with a door that they carry between the two people. The workers are part of the experiment, and as the door passes between the two people, the experimenter is replaced. A large number of people do not notice [...]