Brain and behavior in beginning readers: An event-related potential stud

In an investigation of the event-related potential (ERP) waveform and brain-behavior connections in beginning readers, first grade girls were shown first presentations and immediate repetitions of concrete and abstract known words (e.g., doll, bad), unknown words (e.g., loll ), difficult words (e.g., doubt), and nonwords (e.g., lllo) in list form as ERPs were recorded. Participants were divided into low-ability and high-ability reading groups based on scores on standardized reading tests. High-ability readers had larger N100s to unfamiliar stimuli, implying more attention paid to more difficult stimuli for this group. Alternately, the P200 was larger for low-ability readers, implying more perceptual preprocessing for this group. Low-ability readers also lacked a substantial N400, while high-ability readers evidenced a widely-distributed N400 to all types of stimuli, implying differential postlexical processing between groups. Although the effect of repetition was not significant during the N400 epoch, the ERP repetition effect during the 600--1000 ms epoch was such that repetitions were more positive than first presentations. Across subjects, known and difficult words elicited a repetition effect, while only known words elicited the effect for high-ability readers, and there was no effect for low-ability readers. There was also no concreteness effect for low-ability readers, although abstract and concrete words elicited differential processing in high-ability readers. Overall, the findings suggest that the fledgling word-processing system is more flexible and open to linguistic possibility than the fluent system, and that the N400 can serve as an index of this developmental difference. Moreover, the N400 may serve as an oblique index of the automaticity of lower-level processes that theoretically contribute to the higher-level integration process which the N400 represents.