P300 in detecting concealed information and deception: A review

The impact of reducing cognitive load in RT and P300 concealed information tests with importance related fillers

Lukács et al. (2017) enhanced the Reaction Time Concealed Information Test (RT CIT) by incorporating "filler" items. Fillers are intended to increase attention and cognitive load, which should potentially enhance the P300 based CIT (P300-CIT) too. Despite these hypotheses, Olson et al. (2020) found no clear effects of fillers on P300 amplitude and suggested that excessive cognitive load may counteract an increase in attention. Wojciechowski and Lukács (2022) introduced "importance-related" fillers to the RT-CIT in an imaginary mock crime scenario, theorizing they would be more intuitive and easier for participants to follow. This study aims to replicate their findings in a classic episodic mock crime scenario, and with semantic information, to test if a fillers-related enhancement effect on P300 may be observed when cognitive load is reduced. The study compares three protocols: the importance-themed enhanced CIT (E-CIT), a less cognitively demanding version of the E-CIT, the inducer CIT (I-CIT), and the classic three-stimulus protocol (3SP-CIT). The study investigates whether the I-CIT yields a superior P300-CIT effect due to reduced cognitive load and induced semantic context of importance. Reaction time analyses replicated the RT-CIT effect enhancement in the E-CIT compared to the classic 3SP-CIT. Elevated response times in the E-CIT compared to the 3SP-CIT and I-CIT suggest higher cognitive load in the E-CIT. Response times were comparable between the 3SP-CIT and I-CIT, suggesting similar cognitive load. For the P300-CIT results, similar to Olson et al. (2020), fillers did not affect P300 amplitude or latency in the E-CIT group, with Bayes factors supporting the null. Contrary to expectations, no clear enhancement of P300 was observed in the I-CIT, suggesting that cognitive load imposed by fillers does not counteract P300 amplitude.

A case-by-case analysis of EPN and LPP components within a "one-picture-per-emotion-category" protocol

Stimuli encountered in the environment are continuously evaluated according to their affective stimulus significance. Numerous event-related potential studies have shown that the early posterior negativity (EPN) and the late positive potential (LPP) are larger for high than low arousing emotional pictures. The group approach has been recently extended to the study of the individual case. Usually, many exemplars are used to represent an emotion category. Determining how many pictures are needed to reliably assess affective stimulus evaluation processes at the individual level is crucial when moving toward the goal of exploring idiosyncratic emotional stimuli. Accordingly, in the present study (N = 16), singular images displaying erotic, neutral, and mutilation content were shown 800 times while dense sensor EEG was recorded. At the group level, enhanced EPN and LPP amplitudes for high compared to low arousing stimuli emerged. At the single subject level, significantly larger amplitudes to the erotic than neutral image were observed in 15 out of 16 tests for the EPN and LPP components. Regarding the mutilation image, 15 participants showed a significant EPN effect, while the LPP effect was only found in 10 cases. Notably, emotional modulation of the EPN and LPP was stable over time. The present study contributes to the development of experimental designs tailored to the needs of the case-by-case approach. Since the process of affective stimulus evaluation is considered as a process common-to-all, the use of a singular stimulus exemplar may prove useful to investigate the idiosyncratic nature of emotion.

The trajectory of crime: Integrating mouse-tracking into concealed memory detection

The autobiographical implicit association test (aIAT) is an approach of memory detection that can be used to identify true autobiographical memories. This study incorporates mouse-tracking (MT) into aIAT, which offers a more robust technique of memory detection. Participants were assigned to mock crime and then performed the aIAT with MT. Results showed that mouse metrics exhibited IAT effects that correlated with the IAT effect of RT and showed differences in autobiographical and irrelevant events while RT did not. Our findings suggest the validity of MT in offering measurement of the IAT effect. We also observed different patterns in mouse trajectories and velocity for autobiographical and irrelevant events. Lastly, utilizing MT metric, we identified that the Past Negative Score was positively correlated with IAT effect. Integrating the Past Negative Score and AUC into computational models improved the simulation results. Our model captured the ubiquitous implicit association between autobiographical events and the attribute True, and offered a mechanistic account for implicit bias. Across the traditional IAT and the MT results, we provide evidence that MT-aIAT can better capture the memory identification and with implications in crime detection.

Memory detection with concurrent behavioral, autonomic, and neuroimaging measures in a mock crime

Concealed information test (CIT) has been utilized for long to perform single measurements. The combination of multiple measures outperforms single measures because of the diverse cognitive processes they reflect and the reduction in random errors facilitated by multiple measures. To further explore the performance of the CIT with multiple measurements, 57 participants were recruited and randomly assigned into guilty and innocent groups. Subsequently, simultaneously recorded reaction time (RT), skin conductance responses (SCRs), heart rate (HR), and neuroimaging data were collected from functional near-infrared spectroscopy (fNIRS) to detect participants' concealed information in a standard CIT. The results demonstrated that all indicators including RT (area under the curve (AUC) = 0.87), SCRs (AUC = 0.79), HR (AUC = 0.78), and fNIRS (channel 8, AUC = 0.85) could differentiate guilty and innocent groups. Importantly, the use of multiple indicators achieved higher detection efficiency (AUC = 0.96) compared to the use of any single indicator. These results illustrate the effectiveness and feasibility of integrating multiple indicators for concealed information detection in CIT.

Combining recognition, conflict-monitoring and feedback-related ERPs to detect concealed autobiographical information

This study examined the neural signatures associated with conflict-monitoring, recognition and feedback processing in a feedback Concealed Information Test (fCIT), and also examined whether all the ERPs can be used to detect concealed autobiographical information. Participants were randomly assigned to one of two groups (guilty or innocent) and then tested in the fCIT while undergoing electroencephalograms (EEGs). The results showed that the probe (participants' name) elicited a more negative N200, and a more positive recognition P300 than irrelevants among guilty participants. Additionally, feedback following the probe elicited a larger feedback P300 than feedback following irrelevants. Further, we found that three indicators, including the conflict-monitoring N200, recognition P300, and feedback P300, could significantly discriminate between guilty and innocent participants, whereas the FRN could not. Combining them is highly effective in discriminating between guilty and innocent participants (AUC = 0.91). These findings not only shed light on the neural processing of the fCIT but also suggest the potential of using the fCIT to detect concealed autobiographical information.

Novel Sinusoidal Signal Assisted Multivariate Variational Mode Decomposition Combined With Task-Related Component Analysis for Enhancing SSVEP-Based BCI Performance

Brain-computer interfaces (BCIs) based on steady-state visually evoked potential (SSVEP) have a broad application prospect owing to their multiple command output and high performance. Each harmonic component of SSVEP individually contains unique features, which can be utilized to enhance the recognition performance of SSVEP-based BCIs. However, the existing subband analysis methods for SSVEP, including those based on filter banks and existing mode decomposition methods, have limitations in extracting and utilizing independent harmonic components. This study proposes a sinusoidal signal assisted multivariate variational mode decomposition (SA-MVMD) algorithm that allows the constraint of the center frequencies and narrowband filtering structures of the intrinsic mode functions (IMFs) based on the prior frequency knowledge of the signal. It preserves the target information of the signal during decomposition while avoiding mode mixing and incorrect decomposition, thereby enabling the effective extraction of each independent harmonic component of SSVEP. Building on this, a SA-MVMD based task-related component analysis (SA-MVMD-TRCA) method is further proposed to fully utilize the features within the overall SSVEP as well as its independent harmonics, thereby enhancing the recognition performance. Testing on the public SSVEP Benchmark dataset demonstrates that the proposed method significantly outperforms the filter bank-based control methods. This study confirms the effectiveness of SA-MVMD and the potential of this approach, which analyzes and utilizes each independent harmonic of SSVEP, providing new strategies and perspectives for performance enhancement in SSVEP-based BCIs.

Implications of the novel EU AI Act for neurotechnologies

The EU AI Act, the first comprehensive regulation of AI, came into effect in August. Here, we provide an overview of the provisions that apply to the field of neurotechnology with respect to research and development and neuroscience practice and discuss some implications for the future.

Veracity Judgments Based on Complications: A Training Experiment

Research has shown that complications are more common in truth tellers' accounts than in lie tellers' accounts, but there is currently no experiment that has examined the accuracy of observers' veracity judgments when looking at complications. A total of 87 participants were asked to judge 10 transcripts (five truthful and five false) derived from a set of 59 transcripts generated in a previous experiment by Deeb et al. Approximately half of the participants were trained to detect complications (Trained), and the other half did not receive training (Untrained). Trained participants were more likely to look for complications, but they did not detect them accurately, and thus their veracity judgments did not improve beyond Untrained participants' judgments. We discuss that the training may have been too brief or not sensitive enough to enhance decision-making.

Advanced neuroimaging and criminal interrogation in lie detection

Hidden information is the key to many security issues. If there is a reliable method to determine whether someone withholds information, many issues of this type can be resolved. However, until now, no method has proven to be reliable, but technical discoveries in the field of neuroimaging have caused a surge of new research in this area. Many neuroimaging techniques can be used, but functional magnetic resonance is the newest method, and its use in extracting and evaluating information from subjects could be the most significant, given that it records brain states in parallel with current mental activity/behavior, enabling the establishment of correlational links between them. Because the brain state displayed during fMRI imaging is the dependent variable measured during stimulus/task condition manipulation, it is necessary to use fMRI data in combination with complementary criminal interrogation techniques to gather information. This could be particularly important when standard interrogational techniques are not enough in order to preserve the common good, especially in "ticking bomb" situations. In this study, we review aspects of the possibility of utilizing advanced neuroimaging in combination with criminal interrogation in cases of serious criminal acts that threaten public safety.

From lab to life: assessing the impact of real-world interactions on the operation of rapid serial visual presentation-based brain-computer interfaces

Objective.Brain-computer interfaces (BCI) have been extensively researched in controlled lab settings where the P300 event-related potential (ERP), elicited in the rapid serial visual presentation (RSVP) paradigm, has shown promising potential. However, deploying BCIs outside of laboratory settings is challenging due to the presence of contaminating artifacts that often occur as a result of activities such as talking, head movements, and body movements. These artifacts can severely contaminate the measured EEG signals and consequently impede detection of the P300 ERP. Our goal is to assess the impact of these real-world noise factors on the performance of a RSVP-BCI, specifically focusing on single-trial P300 detection.Approach.In this study, we examine the impact of movement activity on the performance of a P300-based RSVP-BCI application designed to allow users to search images at high speed. Using machine learning, we assessed P300 detection performance using both EEG data captured in optimal recording conditions (e.g. where participants were instructed to refrain from moving) and a variety of conditions where the participant intentionally produced movements to contaminate the EEG recording.Main results.The results, presented as area under the receiver operating characteristic curve (ROC-AUC) scores, provide insight into the significant impact of noise on single-trial P300 detection. Notably, there is a reduction in classifier detection accuracy when intentionally contaminated RSVP trials are used for training and testing, when compared to using non-intentionally contaminated RSVP trials.Significance.Our findings underscore the necessity of addressing and mitigating noise in EEG recordings to facilitate the use of BCIs in real-world settings, thus extending the reach of EEG technology beyond the confines of the laboratory.

Psychology and the lie detector industry: A fifty-year perspective

Fifty years ago, in a trenchant analysis that challenged applied lie detection theory and science, David Lykken (1974) brought polygraphic interrogation methods to the attention of academia with the hope that these techniques would come under the purview of psychology and psychophysiology. In this perspective, I examine how this application of psychophysiology has evolved over the last half century and how its status has changed for 1) the comparison (control) question test (CQT), used in forensic applications; 2) polygraph screening tests, used to evaluate examinee integrity; and 3) the concealed information technique (CIT), used to assess recognition memory of crime details. The criticisms of the CQT and screening tests advanced by Lykken have been amplified and focused by the academic community over the last half century. However, this has had little effect on how these methods are practiced and has not curtailed their use. Although most private sector employee screening tests are now prohibited, personnel screening of government employees has increased, and screening tests of sex offenders are now commonplace. Even though the CIT has captured the interest of psychophysiologists as a scientifically defensible technique, its field use is negligible. A primary purpose of polygraphic interrogations continues to be the extraction of admissions and confessions. The lack of change in the polygraph testing status quo stems in large part from unwavering government support for the use of these methods. As a result, polygraph theory and research support continues to rest on shaky ground while practice continues unfettered by valid criticism.

Resistance of a short-term memory concealed information test with famous faces to countermeasures

The concealed information test (CIT) aims at identifying knowledge that a person wants to hide, by measuring physiological indices during the presentation of known versus unknown items. Recently, Lancry-Dayan et al. (Journal of Applied Research in Memory and Cognition, 7 (2), 291-302, 2018) proposed a new version of this test that included a short-term memory task to maximize differences between responses to items. Participants were asked to memorize four pictures of faces that included one face of an acquaintance. The authors observed that participants looked at the familiar face during the first second and then tended to avoid it. This specific orientation-avoidance pattern occurred even in participants instructed to conceal their familiarity with the known faces (in a spontaneous or a guided manner). In a first experiment, we reproduced Lancry-Dayan et al.'s (2018) study using photos of famous faces. The pattern found by Lancry-Dayan et al. was observed in participants asked to perform the memory task only, participants asked to conceal their familiarity with the famous faces, and participants of a countermeasure group. In a second experiment, we tested the robustness of Lancry-Dayan et al.'s countermeasure. We modified the instructions by emphasizing the oculomotor task or giving feedback. While between-group differences in gaze-pattern appeared after feedback was provided, classification analyses were still able to distinguish between familiar and unfamiliar faces accurately, which revealed the good resistance of this new CIT protocol to countermeasures.

Conditioning to true content and artificial intelligence in psychophysiological intention recognition

OBJECTIVE

The objective is to introduce a novel method for classical conditioning to true content (CtTC), and for the first time, apply this approach in the concealed information test (CIT) to effectively discern intentions. During CtTC, participants are trained to exhibit electrodermal responses whenever they recognize true content on a screen. Additionally, the objective is to evaluate a novel CIT-dataset preprocessing algorithm, employed to enhance machine learning (ML) classification performance.

METHODS

A total of 84 participants were evenly divided into four groups. Two groups of participants devised plans for stealing money from a supermarket, while the other two groups did not engage in any planning. One planning group and one non-planning group underwent CIT examination, while the remaining groups were subjected to CtTC.

RESULTS

The CIT accuracy initially stood at 52 % and increased to 71 % after Z-score and ML classification (McNemar test, p < 0.05). Conversely, the CtTC accuracy was 76 % and significantly improved to 93 % following Z-score and 95 % following ML classification (McNemar test, p < 0.05). In the best-performing classifiers, CtTC exhibited significantly superior metrics for guilty/innocent classification compared to CIT (Fisher's exact test, p < 0.05, power 1 - β > 0.90). In the CtTC group, reactivity and sensitivity significantly increased, indicated by higher EDR amplitudes (p < 0.05, two-tailed t-test, power 1 - β = 0.89) and the number of EDRs (p < 0.05, Fisher's exact test, power 1 - β = 0.90). There was no statistically significant difference between the Z-score and ML classification.

CONCLUSIONS

In the assessment of intentions, CtTC enhances both the sensitivity and accuracy of the CIT.

Unveiling the efficacy of the feedback concealed information test in collaborative crime detection

Collaborative crime poses severe social hazards. In collaborative crime scenarios, previous studies have indicated that perpetrators' collaborative encoding can impair the detection efficiency of P300-based complex trial protocols due to the collaborative encoding deficit. The feedback concealed information test (fCIT), a unique variation of the concealed information test, provides participants with feedback on how well they conceal information from memory. The fCIT, which has proven to be highly efficient, detects concealed information using recognition P300 along with feedback-related event-related potentials, and reflects the subject's motivation to conceal. However, no studies have examined the fCIT's effectiveness in identifying collaborative criminals. We propose that the fCIT's efficiency persists in cases of collaborative crime and test this hypothesis using a sample of 48 participants. The participants in the collaborative groups were instructed to have hushed conversations about theft to simulate the collaborative crime process. Subsequently, they completed the fCIT. The findings indicate a significant decline in recognition P300's detection efficiency when participants committed crimes collaboratively. Nevertheless, the detection efficiency of feedback P300 and feedback-related negativity remained high. This study's outcomes illustrate the capacity of the fCIT to detect perpetrators involved in collaborative crime.

Does deception involve more cognitive control than truth-telling? Meta-analyses of N2 and MFN ERP studies

A number of psychological theories propose that deception involves more cognitive control than truth-telling. Over the last decades, event-related potentials (ERPs) have been used to unravel this question, but the findings are mixed. To address this controversy, two meta-analyses were conducted to quantify the results of existing studies reporting N2 or medial frontal negativity (MFN) associated with deception. In total, 32 papers consisting of 1091 participants were included, which yielded 32 effect sizes for N2 and 7 effect sizes for MFN. We found that deception was associated with a more negative N2 and MFN than truth-telling with medium and large effect sizes (r = .25 and .51, respectively). We also found that the deception paradigm modulated the results (p = .043), but found no evidence for publication bias. Our findings indicate that deception involves more cognitive control than truth-telling. Our review also identifies gaps in this literature, including a need for more ERP studies using spontaneous deception.

Case-by-case: neural markers of emotion and task stimulus significance

The present study assessed the hypothesis that electrophysiological markers of emotional and task stimulus significance can be demonstrated in concert at the level of the individual case. Participants (n = 18, 9 females) viewed low and high-arousing pictures selected from behavior systems of sexual reproduction, disease avoidance, and predator fear. Furthermore, to concurrently manipulate task relevance, participants performed an explicit emotion categorization task with either low or high-arousing pictures alternating as target stimuli in separate experimental blocks. Pooled across behavior systems, event-related components sensitive to emotional significance reached statistical significance in 100% of the tests for the early posterior negativity and in 96% of the tests for the late positive potential. Regarding explicit task relevance, the target P3 effect was significant in 96% of the tests. These findings demonstrate that neural markers of stimulus significance driven by emotional picture content and explicit task demands can be assessed at the individual level. Replicating an effect case-after-case provides strong support for an effect common-to-all and may support individual inferences. Contributions of the case-by-case approach to reveal reproducible effects and implications for the development of neural biomarkers for specific affective and cognitive component processes are discussed.

Meta-Research Perspectives on Verbal Lie Detection

Verbal lie detection (VLD) research, conducted mainly in the cognitive sciences, examines content-based indicators that differ between truth-tellers and lie-tellers. Following the meta-research approach (examination of the research itself), the current paper aimed to ascertain the current status of VLD research across three components: the search for VLD indicators, VLD coding, and VLD research tracks. It highlights several issues that challenge VLD research; these are discussed, along with suggestions for how to address them. This scrutiny may contribute to a further advancement of the field of VLD research and, as a result, an improvement of VLD practices.

Interactive slide selection algorithm and machine learning in psychophysiological memory testing

Objective. To present a new type of concealed information test (CIT) that implements the interactive slide selection (ISS) algorithm and compare its effectiveness with a standard CIT (sCIT).Approach. The ISS algorithm presents slides interactively, based on the analysis of electrodermal activity, while sCIT presents slides in a predefined, sequential order. The algorithm automatically selects irrelevant, relevant, and control slides and presents them at the moment which is physiologically most suitable for electrodermal response detection. To compare the ISS-based CIT (issCIT) and sCIT, two objects, a bag, and a wallet, were presented to 64 participants, 32 of whomwere analyzed with sCIT, and another 32 with issCIT.Main results. The results show that ISS had significantly better true/false predictions (Fisher's exact test,p< 0.01). Also, the number of false positives (FPs) was significantly lower in the issCIT group in comparison with sCIT (Fisher's exact test,p< 0.001). Machine learning (ML) classifiers improved precision from 49% to 79% in the sCIT group (McNemar's test,p< 0.05), and from 85% to 100% in the issCIT group (McNemar's test,p< 0.05). The testing time in the issCIT group ranged between 42 and 107 s, while the average was 53 s. In the sCIT group, the testing time was always 330 s.Significance. Under the presented experimental settings, the ISS algorithm obtained significantly better classification results compared to sCIT, while the application of the ML algorithms managed to improve the classification results in both groups reaching a precision of 100%. The ISS algorithm allowed for a much shorter testing time compared to sCIT.

The path of dishonesty: identification of mental processes with electrical neuroimaging

Much research finds that lying takes longer than truth-telling. Yet, the source of this response time difference remains elusive. Here, we assessed the spatiotemporal evolution of electrical brain activity during honesty and dishonesty in 150 participants using a sophisticated electrical neuroimaging approach-the microstate approach. This uniquely positioned us to identify and contrast the entire chain of mental processes involved during honesty and dishonesty. Specifically, we find that the response time difference is the result of an additional late-occurring mental process, unique to dishonest decisions, interrupting the antecedent mental processing. We suggest that this process inhibits the activation of the truth, thus permitting the execution of the lie. These results advance our understanding of dishonesty and clarify existing theories about the role of increased cognitive load. More broadly, we demonstrate the vast potential of our approach to illuminate the temporal organization of mental processes involved in decision-making.

Brain to Brain Interfaces (BBIs) in future military operations; blurring the boundaries of individual responsibility

Developments in neurotechnology took a leap forward with the demonstration of the first Brain to Brain Interface (BBI). BBIs enable direct communication between two brains via a Brain Computer Interface (BCI) and bypasses the peripheral nervous system. This discovery promises new possibilities for future battlefield technology. As battlefield technology evolves, it is more likely to place greater demands on future soldiers. Future soldiers are more likely to process large amounts of data derived from an extensive networks of humans and machines. This raises several ethical and philosophical concerns. This paper will look at BBI technology in current stages of research, future BBI applications in the military and how the potential use of BBIs in military operations challenges the way we understand the concept of responsibility. In this paper, I propose that an individual connected to a BBI ought not to be held fully responsible for her actions. The justification for this proposition is based on three key points such as an individual connected to a BBI does not have the ability to act freely, has a diminished sense of self-agency and may not be able to demonstrate authenticity of the thoughts and memories generated when connected to the interface.

Verbal Lie Detection: Its Past, Present and Future

This article provides an overview of verbal lie detection research. This type of research began in the 1970s with examining the relationship between deception and specific words. We briefly review this initial research. In the late 1980s, Criteria-Based Content Analysis (CBCA) emerged, a veracity assessment tool containing a list of verbal criteria. This was followed by Reality Monitoring (RM) and Scientific Content Analysis (SCAN), two other veracity assessment tools that contain lists of verbal criteria. We discuss their contents, theoretical rationales, and ability to identify truths and lies. We also discuss similarities and differences between CBCA, RM, and SCAN. In the mid 2000s, 'Interviewing to deception' emerged, with the goal of developing specific interview protocols aimed at enhancing or eliciting verbal veracity cues. We outline the four most widely researched interview protocols to date: the Strategic Use of Evidence (SUE), Verifiability Approach (VA), Cognitive Credibility Assessment (CCA), and Reality Interviewing (RI). We briefly discuss the working of these protocols, their theoretical rationales and empirical support, as well as the similarities and differences between them. We conclude this article with elaborating on how neuroscientists can inform and improve verbal lie detection.

Face familiarity revealed by fixational eye movements and fixation-related potentials in free viewing

Event-related potentials (ERPs) and the oculomotor inhibition (OMI) in response to visual transients are known to be sensitive to stimulus properties, attention, and expectation. We have recently found that the OMI is also sensitive to face familiarity. In natural vision, stimulation of the visual cortex is generated primarily by saccades, and it has been recently suggested that fixation-related potentials (FRPs) share similar components with the ERPs. Here, we investigated whether FRPs and microsaccade inhibition (OMI) in free viewing are sensitive to face familiarity. Observers freely watched a slideshow of seven unfamiliar and one familiar facial images presented randomly for 4-s periods, with multiple images per identity. We measured the occipital fixation-related N1 relative to the P1 magnitude as well as the associated fixation-triggered OMI. We found that the average N1-P1 was significantly smaller and the OMI was shorter for the familiar face, compared with any of the seven unfamiliar faces. Moreover, the P1 was suppressed across saccades for the familiar but not for the unfamiliar faces. Our results highlight the sensitivity of the occipital FRPs to stimulus properties such as face familiarity and advance our understanding of the integration process across successive saccades in natural vision.

Detection of concealed knowledge via the ERP-based technique Brain Fingerprinting: Real-life and real-crime incidents

Brain Fingerprinting (BFP) is an electroencephalogram-based system used to detect knowledge, or absence of knowledge of a real-life incident (e.g., a crime) in a person's memory. With the help of BFP, a potential crime suspect can be classified as possessing crime-related information (Information-Present), not possessing crime-related information (Information-Absent), or Indeterminate (BFP unable to classify a subject). In the lab setting, we compare the ground-truth of a subject (i.e., real-life involvement in an incident) against their classification based on BFP testing. We report two studies: replication of BFP with university students (Study 1) and replication of BFP with parolees (Study 2). In Study 1, we tested 31 subjects (24 females, seven males, mean age = 21.3) on either their own or another subject's real-life incident. BFP correctly classified nine Information-Present and 18 Information-Absent subjects, but with one false positive and three exclusions. In Study 2, we tested 17 male parolees (mean age = 47.5) on their own or another parolee's crime incident. BFP correctly classified two Information-Present and six Information-Absent subjects. However, there was also one false positive classification and three Indeterminates. Additionally, we identified three subjects who could not complete the BFP testing and two exclusions. We posit that BFP is not yet at a stage to be considered a robust and accurate crime-detection tool as claimed in former articles. Nevertheless, after addressing the limitations, BFP has considerable potential as an information detection tool in forensic investigations, especially for detecting idiosyncratic crime-relevant knowledge in a perpetrator, in addition to helping to confirm the accuracy of a suspect's claim of innocence.

Self-deception: Distorted metacognitive process in ambiguous contexts

As one of the commonly used folk psychological concepts, self-deception has been intensively discussed yet is short of solid ground from cognitive neuroscience. Self-deception is a biased cognitive process of information to obtain or maintain a false belief that could be both self-enhancing or self-diminishing. Study 1 (N = 152) captured self-deception by adopting a modified numerical discrimination task that provided cheating opportunities, quantifying errors in predicting future performance (via item-response theory model), and measuring the belief of how good they are at solving the task (i.e., self-efficacy belief). By examining whether self-efficacy belief is based upon actual ability (true belief) or prediction errors (false belief), Study 1 showed that self-deception occurred in the effortless (easier access to answer cues) rather than effortful (harder access to answer cues) cheating opportunity conditions, suggesting high ambiguity in attributions facilitates self-deception. Studies 2 and 3 probed the neural source of self-deception, linking self-deception with the metacognitive process. Both studies replicated behavioral results from Study 1. Study 2 (ERP study; N = 55) found that the amplitude of frontal slow wave significantly differed between participants with positive/self-enhancing and negative/self-diminishing self-deceiving tendencies in incorrect predictions while remaining similar in correct predictions. Study 3 (functional magnetic resonance imaging study; N = 33) identified self-deceiving associated activity in the anterior medial prefrontal cortex and showed that effortless cheating context increased cheating behaviors that further facilitated self-deception. Our findings suggest self-deception is a false belief associated with a distorted metacognitive mental process that requires ambiguity in attributions of behaviors.

Belief or disbelief in feedback influences the detection efficiency of the feedback concealed information test

The feedback concealed information test (fCIT) is a new variant of the CIT that added feedback about participants’ concealing performances in the classical CIT. The advantage of the fCIT is that the resulting feedback related event-related potentials (ERPs) can be used to detect concealed information. However, the detection efficiency of feedback-based ERPs varies across studies. The present experiment examined whether the extent participants believed the feedback influenced their detection efficiency. Specifically, participants did a mock crime and were then tested in a fCIT. Following the fCIT, participants were asked to report how much they believed the feedback was accurate. Results showed that there were no significant correlations between the amplitude of the feedback related negativity (FRN), feedback P300, and participants’ self-report at the group level. However, individual analyses showed that the detection efficiency of both the FRN and feedback P300 were influenced by participants’ belief about the presented feedback. The detection efficiency of the FRN and the feedback P300 was higher among participants who believed the feedback. These findings suggest that the fCIT is dependent to some extent on the participants’ level of belief in the feedback.

A novel and effective item-source complex trial protocol: Discrimination of guilty from both knowledgeable and unknowledgeable innocent subjects

Innocent subjects who are knowledgeable of crime-related information will often be misclassified as "guilty" in P300-based complex trial protocol (CTP). Therefore, it is necessary to develop a more rigorous CTP that can effectively discriminate the guilty from both the knowledgeable and the unknowledgeable innocents. Sometimes the guilty and the knowledgeable innocents possess the same item memories but different source memories. The present study designed a novel item-source complex trial protocol based on the differences of source memory among the three kinds of individuals. Either the crime-related probe (e.g., the stolen ring) or one of the crime-unrelated stimuli (e.g., watch, earring, bracelet, or bangle) (item memory) was presented in the first part of each trail, and either a stealing-source word (e.g., stole) or other-source word (e.g., fetched) (source memory) was presented in the second part of each trail. The results showed that: (1) the P300 evoked by item memory could effectively discriminated the guilty from the unknowledgeable innocent (AUC = 0.76) but failed to effectively discriminate the guilty from the knowledgeable innocent (AUC = 0.60); (2) the late positive component evoked by source memory could effectively discriminated the guilty from both the knowledgeable innocent (AUC = 0.94) and the unknowledgeable innocent (AUC = 0.84) in one test.

Steady-state visual evoked potentials differentiate between internally and externally directed attention

While attention to external visual stimuli has been extensively studied, attention directed internally towards mental contents (e.g., thoughts, memories) or bodily signals (e.g., breathing, heartbeat) has only recently become a subject of increased interest, due to its relation to interoception, contemplative practices and mental health. The present study aimed at expanding the methodological toolbox for studying internal attention, by examining for the first time whether the steady-state visual evoked potential (ssVEP), a well-established measure of attention, can differentiate between internally and externally directed attention. To this end, we designed a task in which flickering dots were used to generate ssVEPs, and instructed participants to count visual targets (external attention condition) or their heartbeats (internal attention condition). We compared the ssVEP responses between conditions, along with alpha-band activity and the heartbeat evoked potential (HEP) - two electrophysiological measures associated with internally directed attention. Consistent with our hypotheses, we found that both the magnitude and the phase synchronization of the ssVEP decreased when attention was directed internally, suggesting that ssVEP measures are able to differentiate between internal and external attention. Additionally, and in line with previous findings, we found larger suppression of parieto-occipital alpha-band activity and an increase of the HEP amplitude in the internal attention condition. Furthermore, we found a trade-off between changes in ssVEP response and changes in HEP and alpha-band activity: when shifting from internal to external attention, increase in ssVEP response was related to a decrease in parieto-occipital alpha-band activity and HEP amplitudes. These findings suggest that shifting between external and internal directed attention prompts a re-allocation of limited processing resources that are shared between external sensory and interoceptive processing.

The effects of practicing a novel countermeasure on both the semantic and episodic memory-based complex trial protocols

This study applied a countermeasure-resistant version of the Concealed Information Test - the Complex Trial Protocol (CTP) - in an information recognition scenario. We replicated and extended the effects of a novel countermeasure developed by Lukács et al., (2016) on both Semantic and Episodic CTPs. We measured participants' response time and P300 event-related potential to rare, crime-relevant probe stimuli, or frequent, non-crime-relevant irrelevant stimuli in two ways: 1) probe vs the average of all irrelevants (PvIall), and 2) probe vs the maximum irrelevant (PvImax). We hypothesized that countermeasure use would only impair information recognition (as indexed by P300) when participants had practiced the countermeasure beforehand. We further hypothesized that recognition of less salient, Episodic information (i.e., jewelry items from a mock crime) would be impaired by countermeasure use more than the recognition of highly salient, Semantic information (i.e., birthdates). Individual diagnostics based on the area under the receiver operating characteristic curve (Semantic CTP: practice n = 22, non-practice n = 23; Episodic CTP: practice n = 19, non-practice n = 18) revealed that the Semantic CTP was affected by the novel countermeasure, but both PvIall and PvImax analyses remained diagnostically useful. The Episodic CTP's performance, however, was reduced to chance, regardless of practice or analysis type. These results are important for both the field of deception detection and the CTP literature. Research on improvements to the Episodic CTP is required.

The effect of mental countermeasures on a novel brain-based feedback concealed information test

The feedback concealed information test (fCIT) is a novel form of the CIT, providing participants with feedback regarding their memory concealment performance. The fCIT utilizes event-related potentials (recognition-P300 and feedback-related event-related potentials) and has been shown to provide high efficiency in detecting information concealment. However, it is unclear how well the fCIT performs in the presence of mental countermeasures. To address this question, participants were trained to use countermeasures during fCIT. Results showed that the recognition-P300 efficiency decreased when participants used countermeasures. However, the efficiencies of feedback-related negativity and feedback-P300 were unchanged, with feedback-P300 still showing a high detection efficiency (AUC = 0.86) during countermeasures. These findings demonstrate the potential of fCIT for subverting countermeasures.

Neural Correlates of Affective Stimulus Evaluation: A Case-by-Case Analysis

A recent study provided first evidence that neural correlates of affective stimulus evaluation, that is, the early posterior negativity (EPN) and late positive potential (LPP), can be assessed at the individual case level. Expanding the case-by-case approach, the main aim of the present study was to explore the process of affective stimulus evaluation within the individual participant with respect to multiple emotional stimulus classes. Towards this end, each participant viewed separate blocks of low and high arousing pictures from behavior systems of predator fear, disease avoidance, and sexual reproduction. 13 out of 16 participants showed larger EPN and LPP amplitudes for higher than lower arousing stimuli for all three behavior systems. Furthermore, rather than indicating a general lack of emotional modulation, cases of non-significant EPN (N= 3) and LPP (N= 2) tests in individual participants appeared to be specific to a single emotion category. Overall, assessing the emotional modulation of the EPN and LPP across multiple behavior systems strengthens the case-by-case approach regarding an effect "common-to-all" as well as by differentiating non-significant effects within individuals in terms of a content-specific or general phenomenon. Implications for revealing a general principle of emotion functioning and biomarker development are discussed.

Forensic Brain-Reading and Mental Privacy in European Human Rights Law: Foundations and Challenges

A central question in the current neurolegal and neuroethical literature is how brain-reading technologies could contribute to criminal justice. Some of these technologies have already been deployed within different criminal justice systems in Europe, including Slovenia, Italy, England and Wales, and the Netherlands, typically to determine guilt, legal responsibility, or recidivism risk. In this regard, the question arises whether brain-reading could permissibly be used against the person's will. To provide adequate legal protection from such non-consensual brain-reading in the European legal context, ethicists have called for the recognition of a novel fundamental legal right to mental privacy. In this paper, we explore whether these ethical calls for recognising a novel legal right to mental privacy are necessary in the European context. We argue that a right to mental privacy could be derived from, or at least developed within in the jurisprudence of the European Court of Human Rights, and that introducing an additional fundamental right to protect against (forensic) brain-reading is not necessary. What is required, however, is a specification of the implications of existing rights for particular neurotechnologies and purposes.

Aging reduces EEG markers of recognition despite intact performance: Implications for forensic memory detection

ERP-based forensic memory detection is based on the logic that guilty suspects will hold incriminating knowledge about crimes they have committed, and therefore should show parietal ERP positivities related to recognition when presented with reminders of their crimes. We predicted that such forensic memory detection might however be inaccurate in older adults, because of changes to recognition-related brain activity that occurs with aging. We measured both ERPs and EEG oscillations associated with episodic old/new recognition and forensic memory detection in 30 younger (age < 30) and 30 older (age > 65) adults. EEG oscillations were included as a complementary measure which is less sensitive to temporal variability and component overlap than ERPs. In line with predictions, recognition-related parietal ERP positivities were significantly reduced in the older compared to younger group in both tasks, despite highly similar behavioural performance. We also observed aging-related reductions in oscillatory markers of recognition in the forensic memory detection test, while the oscillatory effects associated with episodic recognition were similar across age groups. This pattern of results suggests that while both forensic memory detection and episodic recognition are accompanied by aging-induced reductions in parietal ERP positivities, these reductions may be caused by non-overlapping mechanisms across the two tasks. Our findings suggest that EEG-based forensic memory detection tests are less valid in older than younger populations, limiting their practical applications.

Case-by-case: Emotional stimulus significance and the modulation of the EPN and LPP

Stimuli encountered in the environment are continuously evaluated according to their affective stimulus significance. Numerous event-related potential studies have shown that the early posterior negativity (EPN) and the late positive potential (LPP) are larger for pictures high in emotional arousal compared to low arousing images. Here, we used a case-by-case approach to determine the emotional modulation of the EPN and LPP at the level of the individual case. We probed the effect in three studies regarding behavior systems of predator fear, disease avoidance, and sexual reproduction. In each study, high and low arousing pictures from the respective behavior system were presented and event-related brain potentials measured. At the group level, previous findings regarding an enhanced EPN and LPP for high compared to low arousing stimuli were replicated. Novel findings were observed when analyzing each case individually. The majority of participants showed significantly larger EPN and LPP amplitudes to pictures showing threatening compared to harmless animals (15 and 16 out of 16 tests, respectively), images of disease and mutilation compared to neutral people (15 and 17 out of 18 tests, respectively), and high-arousing erotic compared to romantic pictures (17 and 17 out of 17 tests, respectively). Further analyses exploring the tradeoff between specificity and sensitivity suggest reliance on picture categories of sexual reproduction and disease avoidance. Overall, the present findings demonstrate that the case-by-case approach can be useful for revealing a general principle of emotional stimulus processing common-to-all. Implications for the reproducibility of the findings and biomarker development are discussed.

Breakthrough percepts of online identity: Detecting recognition of email addresses on the fringe of awareness

A key issue facing cybercrime investigations is connecting online identities to real-world identities. This paper shows that by combining the Fringe-P3 method with a concealed information test, we can detect a participant's familiarity with their own email address, thus connecting their real-world identity to their online one. Participants were shown Rapid Serial Visual Presentation (RSVP) streams of email addresses, some including their own email address (probe) or a target email address. Familiarity with the probe was accurately detected with significant results at the group level and for 7 of 11 participants at the individual level. These promising results demonstrate that the method can be successfully used to detect online identities. Factors that may affect how well an email address probe stands out in the RSVP streams are also discussed.

Novel Convolutional Neural Network with Variational Information Bottleneck for P300 Detection

In the area of brain-computer interfaces (BCI), the detection of P300 is a very important technique and has a lot of applications. Although this problem has been studied for decades, it is still a tough problem in electroencephalography (EEG) signal processing owing to its high dimension features and low signal-to-noise ratio (SNR). Recently, neural networks, like conventional neural networks (CNN), has shown excellent performance on many applications. However, standard convolutional neural networks suffer from performance degradation on dealing with noisy data or data with too many redundant information. In this paper, we proposed a novel convolutional neural network with variational information bottleneck for P300 detection. Wiht the CNN architecture and information bottleneck, the proposed network termed P300-VIB-Net could remove the redundant information in data effectively. The experimental results on BCI competition data sets show that P300-VIB-Net achieves cutting-edge character recognition performance. Furthermore, the proposed model is capable of restricting the flow of irrelevant information adaptively in the network from perspective of information theory. The experimental results show that P300-VIB-Net is a promising tool for P300 detection.

Is the CIT susceptible to misleading information? A constructive replication

The Concealed Information Test (CIT) utilizes psychophysiological measures to detect crime-related knowledge in a suspect's memory. In other words, it can discriminate between knowledgeable (guilty) and unknowledgeable (innocent) suspects. The majority of CIT research is however conducted in controlled laboratory settings, which are more resistant to external influences than realistic forensic settings. Such influences include retroactive memory interferences which may threaten the validity of the CIT. One notable example is the misinformation effect - retroactive memory distortions caused by exposure to misleading information regarding a past event. The current study is a constructive replication of Volz et al. (J Forensic Sci 2017;63:1419) examining the effects of misleading information on the CIT. Participants underwent a three-stage experiment including a mock crime, exposure to misleading information, and a CIT. Results show that when misleading information was presented, explicit memory of the mock crime was reduced, but the physiological responses to the critical CIT items were only partially attenuated. This could suggest that the detection of crime-relevant information, using skin conductance and respiration measures, might be possible even when suspects are exposed to misleading information.

Concealed information revealed by involuntary eye movements on the fringe of awareness in a mock terror experiment

Involuntary eye movements during fixation are typically inhibited following stimulus onset (Oculomotor Inhibition, OMI), depending on the stimulus saliency and attention, with an earlier and longer OMI for barely visible familiar faces. However, it is still unclear whether OMI regarding familiarities and perceptual saliencies differ enough to allow a reliable OMI-based concealed information test (CIT). In a “mock terror” experiment with 25 volunteers, 13 made a concealed choice of a “terror-target” (one of eight), associated with 3 probes (face, name, and residence), which they learned watching text and videos, whereas 12 “innocents” pre-learned nothing. All participants then watched ~ 25 min of repeated brief presentations of barely visible (masked) stimuli that included the 8 potential probes, as well as a universally familiar face as a reference, while their eye movements were monitored. We found prolonged and deviant OMI regarding the probes. Incorporated with the individual pattern of responses to the reference, our analysis correctly identified 100% of the terror targets, and was 95% correct in discriminating “terrorists” from “innocents”. Our results provide a “proof of concept” for a novel approach to CIT, based on involuntary oculomotor responses to barely visible stimuli, individually tailored, and with high accuracy and theoretical resistance to countermeasures.