Lie Detection With Delay-Response Paradigm To Virtuale Environmental Mock-Crime: An ERP Study

Valuable revelations on the understanding of mechanism of deceit and psychological-physiology are emerging based on behavioral, cognitive neuroscience and Virtual Reality researches. One of the trends in the ERP deception detection is to combine multiple indicators to detect incidentally acquired or personal related information. And the evidence combined CNV and P300 have acceptable deception detection effect in Guilty Knowledge Test after adding feedback variant. In addition, Virtual Reality provides an new approach to obtain the information of mock-crime. This research integrates the Virtual Reality and deception detection with multiple indicators, for the lack of related studies.Subjects with high level motivation execute a killing task in Virtual Environment, then detected by EGI Netstation system according as amplitude of P300 and CNV utilizing Delayed Response GKT paradigm. The effectiveness of P300 and CNV in Virtual Environment was validated after primary experiment. The second study manipulate subjects into guilty and innocent groups in which P300 and CNV reveal good validity in detecting concealed information respectively, as former research reported. And the conclusions are followed:(1) Virtual Environment has the capability to provide a new approach of manipulating mock-crime, which could be utilizing in mock-crime detection of deception study and obtain the similar results compared with traditional mock-crime study(2)On the probe stimuli, P300 is found to be more positive than others at Cz, while CNV come to the most negative amplitude at Fz. Compare with irrelevant stimuli, guilty subjects show more significant P300 and CNV on probe stimuli at Cz, whereas innocent group have no such difference. In addition, guilty group have more significant P300 and CNV amplitude on probe stimuli. (3) P300 is more steadily relative to CNV which has better effect size in high level motivation. Combining the two ERPs could attain more precise effect size of deception detection.(4) In delayed response paradigm, deceit has shorter reaction time, relative to truth. Thus, reaction time is probably unfit for the indicator of deception detection.