Reading senseless sentences: Brain potentials reflect semantic incongruity

Marta Kutas and Steven A. Hillyard

Science 207:203-205 (1980)

In a sentence reading task, words that occurred out of context were associated with specific types of event-related potentials. Word that were physically aberrant (larger than normal) elicited a late positive series of potentials, whereas semantically inappropriate words elicits a late negative wave (N400). The N400 wave may be an electrophysiological sign of the “reprocessing” of semantically anomalous information.