Temporal characteristics of triggering dipole sources of the auditory <Emphasis Type="Italic">P</Emphasis>300 in tasks varying in complexity

The localization and the order of triggering of the equivalent dipole sources of the auditory evoked potential (AEP) P300 component were analyzed in healthy subjects performing tasks that required different degrees of concentration. The AEP P300 was isolated and analyzed in 12 subjects aged 18–23 years. The P300 was recorded via 19 channels in mono- and bimodal tasks using two- and three-stimulus methods of the oddball paradigm. Analysis of the equivalent dipole sources of the P300 component upon hearing sounds showed simultaneous activity of dipole sources located in the temporal areas of both hemispheres and in the right frontal area, as well as in the brainstem, irrespective of the task’s complexity. The counting of sounds in the monomodal task was accompanied by consecutive involvement of the left temporal, right temporal, and left frontal sources in the P300 generation; in the bimodal task, these were, respectively, the left parietal, right temporal and hippocampal, and left frontal sources.