Use of auditory event-related potentials to measure immersion during a computer game

The degree of engagement in a computer game is determined by sensory immersion (i.e. effects of display technology) and challenge immersion (i.e. effects of task demand). Twenty participants played a computer game under two display conditions (a large TV vs. head-mounted display) with three levels of cognitive challenge (easy/hard/impossible). Immersion was defined as selective attention to external (non-game related) auditory stimuli and measured implicitly as event-related potentials (ERPs) to an auditory oddball task. The Immersive Experience Questionnaire (IEQ) was used to capture subjective indicators of immersion. The type of display had no significant influence on ERPs or responses to the IEQ. However, subjective immersion was significantly enhanced by the experience of hard and impossible demand. The amplitude of late component ERPs to oddball stimuli were significantly reduced when demand increased from easy to hard/impossible levels. We conclude that ERPs to irrelevant stimuli represent a valid method of operationalising immersion.