Research On Cognitive Lie Detection Based On Brief Implicit Association Test

Purpose: This research adopts The Brief Implicit Association Test(BIAT)contact memory for criminal subjects simulation test paradigm for testing,at the same time using The event related potential(event-related potential,ERP)technology to investigate The Brief Implicit Association Test midbrain evidence of potential changes,to explore The Brief Implicit Association Test contact effectiveness in lie-detector Test.Method: this research was divided into experiment 1 and experiment 2.Experiment 1 take 2(subjects types: crime/innocent)x 2(task types: congruent/incongruent)of the mix design of experiment,the 40 college students were randomly divided into criminal group,innocent,to distinguish it from innocent group,crime groups before BIAT test will make their reading information and hypothetical criminal crime.Experiment 2 is also adopted on the basis of modified experiment 1(subjects types: crime/innocent)x 2(task types: congruent/incongruent)of the mix design of experiment,the 40 college students were randomly divided into criminal group,innocent,to distinguish it from innocent group,crime groups before BIAT test simulated theft crime,Meanwhile,in experiment 2,ERP technology was used to record the eeg data of subjects in the process of BIAT test.Results: experiment 1:The reaction of the criminal group to task 1(the current condition was inconsistent with the authenticity of plot information)was greater than that of task 2,while The reaction of the innocent group to task 2 was greater than that of task 1,Crime group D effect value less than zero,innocent group is greater than zero.The criminal and innocent groups had shorter and more accurate responses to their congruent tasks,with the detection rate of 82.5%.Experiment 2: behavior data,crime group task 1 and task 3 subjects(the current condition and the plot information authenticity)the average reaction time less than the task 2 and task 4 average reaction time(the current condition and the authenticity of the information is not consistent with plot),on the contrary,innocent group participants task 1 and task 3average reaction time is greater than task 2 and task 4 average reaction time;The crime group and the innocent group also had shorter reaction time and higher accuracy in the congruent task,with a detection rate of 82.9%.In ERP data,incongruent tasks induced greater N400,diminished P300,and diminished LPC components than congruent tasks.Specifically,the main effect of task types of P300,N400 and late positive component LPC was significant in both the criminal group and the innocent group.The average amplitude of P300 in the congruent state was significantly higher than that of P300 in the incongruent state.The amplitude of N400 component in the incongruent state was significantly lower than that of the congruent state.Conclusion: the BIAT Lie detection experiments in reaction time,accuracy and effect on the value of D,it can effectively detect the measured person's true identity,At the same time,the criminal group and the innocent group showed significant differences in cognitive processing characteristics of neuroelectrical indicators in different task types,which also demonstrated the good effectiveness of this paradigm in the field of lie detection.