Involuntary attention in children as a function of sound source location: evidence from event-related potentials.

OBJECTIVES: The present study addressed the question of whether location of the auditory stimulation source affects an involuntary attention triggering to the deviant sounds in a passive oddball paradigm in 8-10-year-old children. METHODS: Using free-field stimulation two late event-related potentials components were examined: the mismatch negativity (MMN), indexing preconscious sound change detection and the P3a, indexing involuntary attention switch. Data were registered to frequency changes in sounds of different complexities in two experimental conditions. In the 'in-front' condition, the sound sequences were presented through the loudspeakers situated in front of a participant on both sides of the video display. In the 'on-sides' condition, the sources of auditory and visual stimuli were separated by moving the loudspeakers to the sides of the participant. RESULTS: The MMN amplitude or the MMN and P3a latencies varied in neither stimulus class significantly as a function of sound location. However, significantly larger P3 amplitude was found in the 'in-front', as compared to the 'on-sides' condition. CONCLUSIONS: The present results indicate enhanced involuntary attention switching in children when unattended auditory events occur within the space attended actively for visual modality. Such study design favouring cross-modal integration can be advantageous when studying involuntary auditory attention and its impairment in children.