School of Psychology and Cognition Institute, University of Plymouth, Plymouth, UK.
Department of General Psychology, University of Padova, Padova, Italy.
Hum Brain Mapp. 2019 Jul;40(10):2899-2916. doi: 10.1002/hbm.24567. Epub 2019 Mar 12.
During the last decade and a half, functional magnetic resonance imaging (fMRI) has been used to determine whether it is possible to detect concealed knowledge by examining brain activation patterns, with mixed results. Concealed information tests rely on the logic that a familiar item (probe) elicits a stronger response than unfamiliar, but otherwise comparable items (irrelevants). Previous work has shown that physical countermeasures can artificially modulate neural responses in concealed information tests, decreasing the accuracy of these methods. However, the question remains as to whether purely mental countermeasures, which are much more difficult to detect than physical ones, can also be effective. An fMRI study was conducted to address this question by assessing the effect of attentional countermeasures on the accuracy of the classification between knowledge and no-knowledge cases using both univariate and multivariate analyses. Results replicate previous work and show reliable group activation differences between the probe and the irrelevants in fronto-parietal networks. Critically, classification accuracy was generally reduced by the mental countermeasures, but only significantly so with region of interest analyses (both univariate and multivariate). For whole-brain analyses, classification accuracy was relatively low, but it was not significantly reduced by the countermeasures. These results indicate that mental countermeasure need to be addressed before these paradigms can be used in applied settings and that methods to defeat countermeasures, or at least to detect their use, need to be developed. HIGHLIGHTS: FMRI-based concealed information tests are vulnerable to mental countermeasures Measures based on regions of interest are affected by mental countermeasures Whole-brain analyses may be more robust than region of interest ones Methods to detect mental countermeasure use are needed for forensic applications.
在过去的十五年中，功能磁共振成像（fMRI）已被用于通过检查大脑激活模式来确定是否可以检测到隐藏的知识，结果喜忧参半。隐藏信息测试依赖于这样一种逻辑，即熟悉的项目（探针）比不熟悉但可比较的项目（无关项）引起更强的反应。以前的工作表明，物理对策可以人为地调节隐藏信息测试中的神经反应，降低这些方法的准确性。然而，问题仍然是，是否可以通过纯粹的心理对策（比物理对策更难检测）也能达到效果。一项 fMRI 研究通过使用单变量和多变量分析来评估注意对策对知识和无知识案例之间分类准确性的影响，从而解决了这个问题。结果复制了以前的工作，并显示了在前额顶叶网络中探针和无关项之间的可靠组激活差异。至关重要的是，心理对策通常会降低分类准确性，但仅在感兴趣区域分析（单变量和多变量）中才具有显著差异。对于全脑分析，分类准确性相对较低，但对策并没有显著降低。这些结果表明，在这些范式可以应用于实际应用之前，需要解决心理对策问题，并且需要开发用于对抗对策或至少检测其使用的方法。 要点：基于 fMRI 的隐藏信息测试易受心理对策的影响基于感兴趣区域的对策受到心理对策的影响全脑分析可能比感兴趣区域的分析更稳健需要用于法医应用的检测心理对策使用的方法。
