A Novel Item-associative Complex Trial Protocol

Item memory-source memory complex trial protocol(i-s CTP)is the first published in the world to measure EEG indicators which can effectively distinguish guilty from knowledgeable innocent.But the i-s CTP is only suitable to distinguish the guilty from the knowledgeable in the theft case.Therefore,this study attempts to make use of the differences in associative memory between guilty and knowledgeable innocent subjects to improve i-s CTP and explore whether item-associative CTP(i-a CTP)can effectively distinguish guilty and innocent people in homicide cases.In the first part of each trial,the probe(e.g.,fruit knife)or irrelevants(e.g.,scissors,kitchen knife,serrated knife,sickle)was randomly presented(i.e.,item memory).In the second part,the targets(e.g.,crime-related words "group counseling room,black backpack,time for each guilty subject to complete the experimental task before the i-a CTP")or the non-targets(e.g.,crime-unrelated words "office,white handbag,time for each knowledgeable innocent subject to complete the experimental task before the i-a CTP")were randomly presented(i.e.,associative memory).The results found that :P300 evoked by item memory can effectively distinguish the guilty group from the unknowledgeable innocent group.(AUC=0.82),but can not effectively distinguish guilty group from knowledgeable innocent group(AUC=0.58).The associative memory evoked late positive postpotential can effectively distinguish the guilty group from the knowledgeable innocent group(AUC=0.90),as well as the guilty group from the unknowledgeable innocent group(AUC=0.76).i-a CTP expands the application scope of the item memory-source memory complex trial protocol,improves the science and accuracy of EEG lie detection technology,and lays a theoretical foundation for carrying out field research in the future and promoting the early application of EEG lie detection conclusions in judicial practice.