Word Meaningfulness and Eventrelated Potentials During Phrase Processing

Evoked Potentials (EP) were recorded to visual presentation of words in phrases. Three EP components, P250, N400, P560, and their dependence on the role that each word plays in the phrase were studied. Subjects were requested to perform a congruity/incongruity task after the presentation of short phrases of two-types that differed in the position of meaningful keywords. We show how these keywords contribute substantially to N400 and possibly to P560 but do not reliably affect P250.