An event-related potential study of older children with an early history of failure to thrive

Elementary and junior high school children (n = 13), who were diagnosed wit h nonorganic failure to thrive (FTT) as infants and toddlers, were compared with a normal control group (n = 14) on visual event-related potentials (E RPs) elicited during a primed lexical decision task. Positive stimuli were real words that were identical to the priming stimuli; negative stimuli wer e nonpronounceable letter strings. Although the groups did not differ in wo rd-list reading level, the former FTT group had slower reaction (decision) times and did not show ERP evidence of priming in the N400 epoch. Anterior sites yielded better separation of the real words and letter strings than p osterior sites. A late anterior component between 500 msec to 650 msec post stimulus onset showed the largest condition effect for both groups. The con trol group had a larger negative going late anterior component to words tha n the FTT group. The combined reaction time and ERP findings point to less automatized word recognition in the FTT group.