Abstract: Psychophysiological detection of deception has garnered increasing attention in both research and applied settings. Deception detection using autonomic responses has been studied for nearly a century. The Concealed Information Test (CIT) is one of the polygraph techniques. In the CIT, question items are chosen so that an examinee with no knowledge about the crime would not be able to discriminate between crime-relevant and irrelevant items. This study aimed to examine the influence of testing time for detecting crime details, and the skin conductance response activity (SCR) was registered by 16-channel polygraph. Meanwhile, this study also examined whether the testing time had influence on distinguishing the guilty group and the informed innocent group. 68 university students participated the study. They were randomly divided into 2 groups: ’guilty’, who committed the mock-crime; ’informed innocent’, who were exposed the mock-crime relevant details by reading newspaper. Half of the participants in the each group needed to do the test immediately, another were tested in 1 week later. All participants needed to have the recognition memory test after CIT. The CIT was consist of central problems (which were the core details of the mock-crime) and peripheral problems (which were the environment details of the mock-crime). The results showed that: (1) for the change of skin conductance response activity, the SCR change of central problems was significant greater than those of peripheral problems, and the SCR change in the immediate test was significant greater than that in the delayed test. There was a significant interaction between the type of test and the type of participant, When the test immediately, there was no significance between the guilty group and the informed innocent group, but when the test delayed, the SCR change of the ‘informed innocent’ group was smaller than those of the guilty group; (2) as for the recognition rate, the recognition accuracy of central problems was higher than those of peripheral problems, the recognition accuracy in the immediate test was higher than that in the delayed test. There was a significant interaction between the type of test and the type of participant, there was no significant difference between the guilty group and the informed innocent group in the immediate test, but in the delayed test, the recognition accuracy of the guilty group was significant higher than those of the informed innocent group for the peripheral problems; (3) the detection rate in the immediate test was larger than that in the delayed test, the interaction of the type of test and the type of participant was also significant, there was no significant difference between immediate test and delayed test of the guilty group, but the detection rate in the delayed test was lower than that in the immediate test for the informed innocent group. The present findings suggested that it was easier to detect ‘guilty’ and ‘informed innocent’ in the delayed test, and the detection rate declined in the delayed test, but it also helped to reduce the danger of detecting the ‘informed innocent’ as ‘guilty’.

Key words: Concealed Information Test, Time, Skin Conductance Response, Memory

摘要： 记录模拟犯罪者和阅读报纸后对案件知情的无辜者接受隐藏信息测试时的皮肤电活动，探讨时间对犯罪隐藏信息记忆的影响。结果发现：(1)延迟条件下，模拟犯罪组的再认率和皮肤电活动变化显著高于知情无辜组，但两组在立即条件下无差异；(2)知情无辜组在延迟条件下的甄别率显著低于立即条件下，而模拟犯罪者在两种条件下无差异。结果表明，延迟测试比立即测试更容易区分模拟犯罪组和知情无辜组；犯罪甄别率在延迟条件下减少，但也减少了知情无辜者被判断为犯罪者的风险。

关键词: 隐藏信息测试, 时间, 皮肤电活动, 记忆