TheP300,anendogenoussubcomponentoftheevent-relatedpotential,isthoughttoreflectcognitiveprocesses.Theevent-relatedpotentialevokedbytheold-newmemoryrecognitiontaskintheoddballparadigmissuitableforexaminingtheneuralprocessesinvolvedinmalingeredneurocognitivedeficits.Forty-fourundergraduateswererandomlyassignedtoasimulatedmalingeringgroupandatruth-tellinggroup.Another22patientswithheadinjurieswereenrolledasacontrolgroup.Allparticipantscompletedtheold-newmemoryrecognitiontaskintheoddballparadigm.ThemeanP300amplitudeofthesimulatedmalingeringgroupwassignificantlyreducedcomparedwiththetruth-tellinggroup(P<0.01),butwasincreasedcomparedwiththecontrolgroup(P<0.01).TheseresultsrevealedthattheP300,evokedbytheold-newmemoryrecognitiontaskoftheoddballparadigm,maybeahelpfulindicatorfordeterminingcognitivemalingering.