Scalp topography of event-related brain potentials and cognitive transitions during childhood.

Examined the relation between cognitive development (CGD) and the ontogenesis of event-related brain potentials (ERPs) during childhood among 48 girls (aged 5-7 yrs). The level of CGD was assessed with a standard Piagetian conservation kit. Ss performed a visual selective attention (oddball) task and an experimental analog (EA) of the Piagetian conservation of liquid quantity task. The ERPs obtained in the EA of the conservation task were characterized by a broad positivity with a centroparietal scalp distribution. The broad positivity discriminated significantly between nonconservers and conservers but not between age groups. These findings received additional support from topographic and symmetric dipole analyses of the ERPs. The results of a dipole analysis suggested more anterior ERP sources for the nonconservers during the early part of stimulus analysis and more lateralized ERP sources for conservers during the later part of information processing.