From the study: "Thirteen first-person shooting games from the Call of Duty, Battlefield, Killzone, Medal of Honor and Resistance: Fall of Man series were chos

From the study: "Thirteen first-person shooting games from the Call of Duty, Battlefield, Killzone, Medal of Honor and Resistance: Fall of Man series were chosen based on their highly similar gameplay tasks and demands. Participants only played the single player campaigns and did not play any multiplayer components of the games." Single player for most of these games is very boring and requires little thinking. They need to add another category to this study where they are playing competitive multiplayer fps. Maybe even specifically strategy game types like capture the flag.