Event related potentials during the visual discrimination of words and pseudowords by children

Abstract

Event related potentials (ERPs) in reading were studied in children in a word and pseudoword discriminating task. Seventy-nine children (9 to 11 year old), all with no elements suggesting brain injury and with school performance compatible with their age were studied. The ERP were registered as there were presented, visually, successively and in a random manner, 100 words and 100 pseudowords. For each stimulus the child pressed a key corresponding to the discrimination between word and pseudoword. The register was carried out for the electrodes of the 10-20 system and the mean amplitudes and latency peaks measured and also the amplitude from 200 to 550 milliseconds. The most significant differences between the ERPs occurred in Cz, with greater negativity for the mean of the amplitude between 425 and 550 milliseconds for pseudowords (N400). The N400 was more precocious in 11 year old. The influence of age was thus evident and also the differences in ERPs between words and pseudowords. © 2006 Associação Arquivos de Neuro-Psiquiatria.