The recognition potential, word difficulty, and individual reading ability: on using event-related potentials to study perception.

Ten observers detected words in a stream of random letters. The latency of the recognition potential (RP) was less for easier words. This implicated short latency processes in word detection. Reaction time (RT) and P3 latency decreases with training were attributed to improved motor preparation. The RT decrease with training was correlated with P3 (r = .67), but not RP (r = .04), latency reduction. P3 latency did not predict individual RT (r = .20), but RP latency did (r = .66). Twenty other subjects took the Verbal portion of a Graduate Record Examination to test whether the RP might be a better predictor of individual differences than P3. RP latency predicted a person's reading score (r = -.74), but P3 latency did not (r = .08). The word-difficulty effect and the shorter RP latency observed for superior readers supported the idea that the RP reflects perception that is based on language skill.