Ambach Wolfgang, Stark Rudolf, Peper Martin, Vaitl Dieter
Institute for Frontier Areas of Psychology and Mental Health, Freiburg, Germany.
Int J Psychophysiol. 2008 Nov;70(2):95-104. doi: 10.1016/j.ijpsycho.2008.07.002. Epub 2008 Jul 15.
The Concealed Information Test (CIT) requires the examinee to deceptively deny recognition of known stimuli and to truthfully deny recognition of unknown stimuli. Because deception and orienting are typically coupled, it is unclear how exactly these sub-processes affect the physiological responses measured in the CIT. The present study aimed at separating the effects of deception from those of orienting. In a mock-crime study, using a modified CIT, thirty-six of seventy-two subjects answered truthfully ('truth group'), whereas the other thirty-six concealed their knowledge ('lie group'). Answering was delayed for 4 s after item presentation. Electrodermal activity (EDA), respiration (RLL), and phasic heart rate (HR) were recorded. A decomposition of EDA responses revealed two response components; the response in the first interval was expected to indicate orienting, stimulus evaluation, and answer preparation, whereas the response in the second interval was assumed to reflect answer-related processes. Inconclusively, both EDA components differentiated between 'probe' and 'irrelevant' items in both groups. Phasic HR and RLL differed between item classes only in the 'lie' group, thus reflecting answer-related processes, possibly deception, rather than merely orienting responses. The findings further support the notion that psychophysiological measures elicited by a modified CIT may reflect different mental processes involved in orienting and deception.
隐蔽信息测试(CIT)要求受测者欺骗性地否认对已知刺激的识别,并如实否认对未知刺激的识别。由于欺骗和定向通常相互关联,目前尚不清楚这些子过程究竟如何影响CIT中测量的生理反应。本研究旨在区分欺骗和定向的影响。在一项模拟犯罪研究中,使用改良的CIT,72名受试者中有36人如实作答(“真话组”),而另外36人隐瞒了他们所知道的信息(“说谎组”)。在呈现项目后,回答延迟4秒。记录了皮肤电活动(EDA)、呼吸(RLL)和心率变异性(HR)。对EDA反应的分解揭示了两个反应成分;预计第一个时间段的反应表明定向、刺激评估和回答准备,而第二个时间段的反应被认为反映了与回答相关的过程。结果不明确,两组中EDA的两个成分均能区分“探测”项目和“无关”项目。只有在“说谎”组中,项目类别之间的心率变异性和呼吸频率存在差异,因此反映了与回答相关的过程,可能是欺骗,而不仅仅是定向反应。这些发现进一步支持了这样一种观点,即改良的CIT引发的心理生理测量可能反映了定向和欺骗中涉及的不同心理过程。