Peth Judith, Sommer Tobias, Hebart Martin N, Vossel Gerhard, Büchel Christian, Gamer Matthias
Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Neuroimage. 2015 Jun;113:164-74. doi: 10.1016/j.neuroimage.2015.03.051. Epub 2015 Mar 25.
Recent research revealed that the presentation of crime related details during the Concealed Information Test (CIT) reliably activates a network of bilateral inferior frontal, right medial frontal and right temporal-parietal brain regions. However, the ecological validity of these findings as well as the influence of the encoding context are still unclear. To tackle these questions, three different groups of subjects participated in the current study. Two groups of guilty subjects encoded critical details either only by planning (guilty intention group) or by really enacting (guilty action group) a complex, realistic mock crime. In addition, a group of informed innocent subjects encoded half of the relevant details in a neutral context. Univariate analyses showed robust activation differences between known relevant compared to neutral details in the previously identified ventral frontal-parietal network with no differences between experimental groups. Moreover, validity estimates for average changes in neural activity were similar between groups when focusing on the known details and did not differ substantially from the validity of electrodermal recordings. Additional multivariate analyses provided evidence for differential patterns of activity in the ventral fronto-parietal network between the guilty action and the informed innocent group and yielded higher validity coefficients for the detection of crime related knowledge when relying on whole brain data. Together, these findings demonstrate that an fMRI-based CIT enables the accurate detection of concealed crime related memories, largely independent of encoding context. On the one hand, this indicates that even persons who planned a (mock) crime could be validly identified as having specific crime related knowledge. On the other hand, innocents with such knowledge have a high risk of failing the test, at least when considering univariate changes of neural activation.
最近的研究表明，在隐蔽信息测试（CIT）中呈现与犯罪相关的细节会可靠地激活双侧额下回、右侧额内侧和右侧颞顶叶脑区网络。然而，这些发现的生态效度以及编码背景的影响仍不明确。为了解决这些问题，三组不同的受试者参与了本研究。两组有罪受试者通过计划（有罪意图组）或实际实施（有罪行为组）一个复杂、逼真的模拟犯罪来编码关键细节。此外，一组知情无辜受试者在中性背景下编码了一半的相关细节。单变量分析显示，在先前确定的腹侧额顶叶网络中，已知相关细节与中性细节之间存在强烈的激活差异，而实验组之间没有差异。此外，当关注已知细节时，各组神经活动平均变化的效度估计相似，并且与皮电记录的效度没有实质性差异。额外的多变量分析为有罪行为组和知情无辜组之间腹侧额顶叶网络的不同活动模式提供了证据，并且在依赖全脑数据时，检测与犯罪相关知识的效度系数更高。总之，这些发现表明基于功能磁共振成像的CIT能够准确检测隐蔽的与犯罪相关的记忆，很大程度上独立于编码背景。一方面，这表明即使是计划（模拟）犯罪的人也能被有效识别为具有特定的与犯罪相关的知识。另一方面，拥有此类知识的无辜者有很高的测试失败风险，至少在考虑神经激活的单变量变化时是这样。
