Participants were observed inside a controlled setting while Zimbardo and a British psychologist analyzed their behavior.

Mhairi Kent, a British psychologist, hears a strange noise coming from her car one day and pulls over to investigate.

Michael Howe (1940-2 January 2002) was a British cognitive psychologist.

Liam Hudson (1933-2005) was a British social psychologist and author.

He was a British experimental psychologist who focused on the mistakes people made when recalling new information.

John Seddon is a British occupational psychologist and author, specialising in the service industry.

In 2001, Wilson was ranked among the 10 most frequently cited British psychologists in scientific journals.

Robert Wood is a British psychologist and writer.

Anjula Mutanda (born 1974) is a British psychologist, life coach and therapist.

Writing in a medical journal, one British psychologist called it "an exercise in mega-silliness."