# The processing of good-fit semantic anomalies -An ERP investigation **Keywords:** Semantic anomalies Shallow processing N400 P600 LPP Language comprehension P2 Moses illusion **Opening (not a real abstract):** The failure-to-detect good-fit semantic anomalies is taken as evidence for shallow semantic processing, however the cognitive mechanisms involved are not well understood. To investigate this we recorded event-related potentials (ERPs) to sentences that contained good and poor-fit semantic anomalies and non-anomalous controls. Detected good-fit anomalies elicited an N400 effect when detection accuracy was stressed, indicating the registration of the anomaly. ERP analyses further ruled out that anomaly non-/detection is due to differences in initial word encoding or in processing prior contextual information. In addition, starting in the P2 interval, the ERP waveform was less positive for nondetected than detected anomalies and non-anomalous controls, presumably reflecting a languagedriven modulation of visual input processing. And finally, detection of good-fit anomalies may also