A New Method for EEG-Based Concealed Information Test

Forensic electroencephalogram (EEG)-based lie detection has recently begun using the concealed information test (CIT) as a potentially more robust alternative to the classical comparative questions test. The main problem with using CIT is that it requires an objective and fast decision algorithm under the constraint of limited available information. In this study, we developed a simple and feasible hierarchical knowledge base construction and test method for efficient concealed information detection based on objective EEG measures. We describe how a hierarchical feature space was formed and which level of the feature space was sufficient to accurately predict concealed information from the raw EEG signal in a short time. A total of 11 subjects went through an autobiographical paradigm test. A high accuracy of 95.23% in recognizing concealed information with a single EEG electrode within about 20 seconds demonstrates effectiveness of the method.