The study used a set of mini-games to test a person’s skill. They played with a pair of other researches, with or against them. The researchers were not actually playing. The games they played had predetermined endings.
Some of the games the researchers won. Some of them the test players won.
When we’re competing with a strong player, we tend to downgrade our own ability. But when that player is on our team, we see ourselves as better than we really are.
Marco K. Wittmann, Nils Kolling, Nadira S. Faber, Jacqueline Scholl, Natalie Nelissen, Matthew F. S. Rushworth “Self-Other Mergence in the Frontal Cortex during Cooperation and Competition” Neuron, Volume 91, July 2016