The negative slow wave (NSW) is a late component of the event-related potential (ERP) in man modulated like the P300 by the stimulus, the task, and the response demand. Aiming at the development of a minipig model of schizophrenia, we investigated scalp ERPs in an auditory P300 paradigm in six Göttingen minipigs. Before training, we observed no difference between target and nontarget NSW. After training, target NSW amplitude was increased 50% compared to nontarget. A P350 was recognized, but the finding of a lack of target/nontarget difference is not conclusive.