Abstract: A method of improving a computer game, the method including the steps of: (a) causing a player to play the computer game in which various game situations are presented to the player during the course of the game; (b) recording game situation parameters corresponding to the various game situations of step (a); (c) determining brain activity of the player during each of the game situations which are presented to the player; (d) evaluating effectiveness of the game situation parameters by reference to brain activities determined in step (c) for each of the game situation parameters recorded in step (b); and (e) improving the game by eliminating or modifying those game situations which have low levels of brain activity as determined in step (d).