Memory detection using fMRI — Does the encoding context matter?

• Published in: NeuroImage (Orlando, Fla.) Vol. 113; pp. 164 - 174
• Main Authors: Peth, Judith, Sommer, Tobias, Hebart, Martin N., Vossel, Gerhard, Büchel, Christian, Gamer, Matthias
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.06.2015; Elsevier Limited
• Subjects: Adult; Brain Mapping; Brain research; Concealed Information Test; Crime - psychology; Deception; Electrodermal responses; Encoding context; Female; Functional Laterality - physiology; Functional MRI; Galvanic Skin Response; Guilt; Humans; Image Processing, Computer-Assisted; Laboratories; Lie Detection - psychology; Magnetic Resonance Imaging - methods; Male; Medical imaging; Memory; Memory - physiology; Mock crime; Multivariate pattern analysis; Nerve Net - anatomy & histology; Nerve Net - physiology; NMR; Nuclear magnetic resonance; Parietal Lobe - physiology; Physiology; Prefrontal Cortex - physiology; Psychomotor Performance - physiology; Recognition (Psychology) - physiology; Studies; Validity; Young Adult; Concealed Information Test; Encoding context; Electrodermal responses; Multivariate pattern analysis; Memory; Mock crime; Functional MRI
• ISSN: 1053-8119; 1095-9572; 1095-9572
• DOI: 10.1016/j.neuroimage.2015.03.051

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. •Recognition of crime details reliably activates a ventral fronto-parietal network.•Concealed memories can be detected irrespective of encoding context.•Multivariate analyses in previously defined ROIs allow for detecting guilty action.•Univariate analyses and electrodermal data reach comparable validity estimates.•Whole brain multivariate analyses show potential to increase the CIT's validity.