Progress of Keystroke Dynamics in Deception Research / 法医学杂志

Traditional polygraph techniques mostly rely on the changes of an individual's physiological indicators, such as electrodermal activity, heart rate, breath, eye movement and function of neural signals and other indicators. They are easily affected by individual physical conditions, counter-tests, external environment and other aspects, and it is difficult to conduct large-scale screening tests based on the traditional polygraph techniques. The application of keystroke dynamics to polygraph can overcome the shortcomings of the traditional polygraph techniques to a large extend, increase the reliability of polygraph results and promote the validity of legal evidence of polygraph results in forensic practice. This paper introduces keystroke dynamics and its application in deception research. Compared with the traditional polygraph techniques, keystroke dynamics can be used with a relatively wider application range, not only for deception research but also for identity identification, network screening and other large-scale tests. At the same time, the development direction of keystroke dynamics in the field of polygraph is prospected.

Application of Eye Tracker in Lie Detection / 法医学杂志

Objective To investigate the application value of eye tracking in lie detection. Methods The 40 subjects were randomly divided into two groups. The pupil diameter, fixation duration, points of fixation and blink frequency of the subjects in the experimental group in observing target stimulation and non-target stimulation were recorded with eye tracker after they accomplished the mock crime. The eye movement parameters of subjects in the control group were directly collected. The differences in eye movement parameters of the experimental group and the control group in observing target stimulation and non-target stimulation were analyzed by t-test. Pearson coefficient analysis of correlation between eye movement parameters that had differences was conducted. The effectiveness of eye movement parameters to distinguish between the experimental group and the control group was calculated by the receiver operator characteristic （ROC） curve. Results Participants from the experimental group had shorter average pupil diameter, longer average fixation duration and fewer fixation points （P<0.05）, but the differences in blink frequency had no statistical significance. The differences in the above indicators of the control group in observing target stimulation and non-target stimulation had no statistical significance. The average fixation duration showed a negative correlation with fixation points （r=-0.255, P<0.05）; the average fixation duration showed a negative correlation with average pupil diameter （r=-0.218, P<0.05）; the fixation points showed a positive correlation with average pupil diameter （r=0.09, P<0.05）. The area under the curve of average pupil diameter, average fixation duration and fixation points was 0.603, 0.621 and 0.580, respectively. Conclusion The average pupil diameter, average fixation duration and fixation points obtained by the eye tracker under laboratory conditions can be used to detect lies.

Polygraph Accuracy of Control Question Test in Criminal Cases / 法医学杂志

Objective To explore polygraph accuracy of Control Question Test （CQT）and whether it could be influenced by examinee's education level and type of violation of law. Methods Real cases of CQT （n=104） and the data from MAO （n=296） were collected. The polygraph accuracy of CQT was calculated. Variance analysis on three groups of different education levels was used to compare their age, and then the chi-square test was employed to compare polygraph accuracy among the groups. Independent sample t test was used to compare the age of subjects in the two groups of different types of violation of law, and then chi-square test was used to compare the true positive rate and true negative rate of lie detection after integration. Results In CQT lie detection of criminal cases, the true positive rate was 87.00%, the false negative rate was 13.00%, the true negative rate was 82.20%, and the false positive rate was 17.80%. There was no statistical significance in the differences between the true positive rate and the true negative rate （P>0.05）. In CQT lie detection of the groups of different education levels, there was no statistical significance in the differences between the true positive rates （P>0.05） while the differences between the true negative rates had statistical significance （P<0.05）. There was no statistical significance in the differences of both the true positive rates and the true negative rates between the violent violation of law and non-violent violation of law （P>0.05）. Conclusion There is no significant difference between the efficiency of CQT lie detection of identifying criminals and excluding innocents. However, a comparatively high false positive rate and false negative rate still exist. The efficiency of CQT lie detection identifying criminals may not influenced by the examinee's education level and type of violation of law, but its efficiency of excluding innocents may be influenced by the examinee's education level.

Detecting Deception Using Neuroscience : A Review on Lie Detection Using Functional Magnetic Resonance Imaging

Since the early 2000s, there has been a continued interest in lie detection using functional magnetic resonance imaging (fMRI) in neuroscience and forensic sciences, as well as in newly emerging fields including neuroethics and neurolaw. Related fMRI studies have revealed converging evidence that brain regions including the prefrontal cortex, anterior cingulate cortex, parietal cortex, and anterior insula are associated with deceptive behavior. However, fMRI-based lie detection has thus far not been generally accepted as evidence in court, as methodological shortcomings, generalizability issues, and ethical and legal concerns are yet to be resolved. In the present review, we aim to illustrate these achievements and limitations of fMRI-based lie detection.

[Implementation and designing of line-detection system based on electroencephalography [EEG]]

In Brain-based lie detection systems which have been recently introduced as substitutes or classic lie detection systems, the procedure for recognition of guilty and innocent subjects is done by inspection of brain signals which are acquired during the specific Polygraph test. With the aim of increasing the performance, this paper presents a powerful method for detection of Guilty persons in lie detection systems using brain signals. It was an experimental study. The employed method is based on the extraction of P300 components from brain signals. In this way, the test protocol was designed based on Odd-ball method, firstly. This test was done on 16 people and their brain signals were acquired. After preprocessing, p300 amplitude was extracted for each person from brain signals, and finally Guilty and Innocent persons were classified by comparing amplitude through Bootstrapped Amplitude Difference [BAD] method. The obtained results show that the proposed method has detected correctly 7 out of 8 guilty persons and 8 out of 8 innocent persons. Also, the validated results show the promise of the proposed approach in discrimination of guilty subjects from innocent subjects by the accuracy of 93.75%. Knowing the existence of precious information in brain signals and their relation with brain's cognitive activities and also considering the performance of the proposed method, there are enough reasons use the proposed approach for detection of guilty persons from innocent ones. Further, in comparison with previous methods, the impact of man ability to control brain signal parameters and creating incorrect feelings been reduced through the proposed method

Studies on the ERP underlying premeditated and temporary deception / 生物医学工程学杂志

The event-related potential (ERP) P300 was recorded to analyze the temporal sequences character and the P300 compositions in premeditated and temporary deception. When 15 healthy undergraduates watched the stolen, familiar but not stolen and strange object pictures, the reaction time was recorded and EEG data were collected to analyze the amplitudes of N1, N2 and P3 sub-component of P300 in honesty and deception group respectively through analog theft paradigm. The results showed that the amplitudes of N1, N2 and P3 in premeditated deception group were markedly larger than those in temporary deception, and the reaction time of deception group was longer than that of honesty group. Compared with temporary deception, more attention resources were invested and intensely response conflict was induced by premeditated deception.

Functional MRI analysis of deception among people with antisocial personality disorders / 中南大学学报(医学版)

OBJECTIVE@#To investigate the functional magnetic resonance imaging (fMRI) data of deception in antisocial personality disorders (ASPD).@*METHODS@#A total of 32 criminals meeting the criteria for ASPD underwent fMRI at 1.5T while responding truthfully questions or lying. We compared the brain activities between truth-telling and lie-telling, and then computed the correlation coefficient between the contrast brain activities and the inclination to deception.@*RESULTS@#The left anterior cingulate gyrus, the bilateral dorsolateral prefrontal cortex, and left inferior parietal lobule were associated with the executive aspects of deception among people with ASPD. But with the greater inclination to deception, the blood oxygen level dependent (BOLD) activities in those regions decreased.@*CONCLUSION@#Evaluations of truthful and untruthful communications pertaining to ASPD subjects may be differentiated in terms of brain BOLD activities, though those activities may decrease in habitual liars, which remains a challenge to the diagnostic accuracy in lie detection.

Falsas alegações de abuso sexual infantil: o contexto do trabalho do psicólogo brasileiro / False allegations of child sexual abuse: the context of Brazilian psychologist practice

Em face a constantes mudanças e atualizações necessárias ao trabalho do psicólogo, este artigo pretende abordar problemáticas emergentes na área da psicologia jurídica que surgem em avaliações psicológicas e nas emissões de documentos escritos em casos de alegação de abuso sexual infantil. Novas discussões têm sido geradas no meio profissional, como por exemplo, a respeito das falsas alegações de abuso sexual e dos falsos testemunhos infantis, que aparecem muitas vezes ligados ao contexto de separação litigiosa ou da Síndrome de Alienação Parental como sustentam alguns especialistas. A discussão das falsas alegações praticamente inexiste na literatura da psicologia brasileira anteriormente ao ano 2000. Pretendemos debater a matéria de forma a trazer questionamentos a pratica profissional, além de identificarmos algumas crenças que podem influenciar o trabalho do psicólogo, contribuir com novas abordagens, teorias e métodos ao assunto em evidência. O estudo ainda busca atualizar alguns determinantes sociais, históricos, culturais e profissionais que envolvem o presente tema, como importante elemento ao entendimento das questões trazidas. O artigo se destina aos operadores de direito em geral, aos psicólogos que atuam tanto em instituições especializadas em abuso sexual infantil como no consultório particular.

In the face of constant change and needed updates in the psychologist’s work, this article intends to deal with emerging problems in Forensic Psychology that arise in psychological assessments and the issue of written documents pertaining to child sexual abuse allegations. New discussions have been generated in the professional field, regarding, for instance false allegations of child sexual abuse and children’s false testimonies, that often appear linked to situations of contested divorces or Parental Alienation Syndrome as supported by some specialists. The discussion of false allegations is practically non-existent in Brazilian psychology literature before the year 2000. We intend to debate the theme in order to bring into question aspects of professional practices, in addition to identifying certain beliefs which can influence the psychologist’s work, to contribute new approaches, theories and methods to the subject in qustion. The study also seeks to update some social, historical, cultural and professional determinants involving this subject, as an important element in the understanding of the questions brought up. The article is aimed at operators of law in general, and to psychologists who work both in institutions specialized in child sexual abuse as well as in private practice.

Identification of mentality facticity based on multi-channel event-related potentials / 生物医学工程学杂志

This paper explores the use of multi-channel event-related potentials (ERP) to identify mentality facticity or detect lie. Some identifiably meaning information, such as subjects' name and birthday, were selected as concealed information to be identified, 15 subjects were tested by concealed information test (CIT) paradigm and their electroencephalographs (EEG) were recorded from 30 electrodes. In virtue of analysis on the statistically significant difference between multi-channel ERPs evoked by probe information and that evoked by irrelevant information, the P300 amplitudes of 15 electrodes were selected as F-test samples. The significant difference of feature sample values between probe and irrelevant information was applied to identify mentality facticity. The results indicate that P300 amplitudes evoked in many electrodes are significantly different between probe and irrelevant information (P < 0.01). According to the significant difference of space sample values between probe and irrelevant information, the detection correctness to probe information reaches to 93.3% and is better than that of methods based single-channel ERP. The method proposed has the advantages of non-invasion and better accuracy, which could be used to identify mentality facticity effectively.

Falsas denúncias e o Diagnóstico diferencial das alegações de abuso sexual / False statements and the differential diagnosis of abuse allegations

O objetivo deste artigo é classificar e definir as várias formas de alegações de abuso sexual infantil, uma vez que os psiquiatras infantis não têm uma forma consistente de classificá-las e em função de não haver definições gerais aceitas sobre as muitas formas as quais as alegações podem surgir. Método: o autor fez uma revisão de 40 artigos, capítulo e livros que contém exemplos de falsas alegações de abuso sexual feitas por crianças e seus cuidadores. Resultado: Este artigo explica os conceitos de programação, sugestão, fantasia, delírio, má interpretação, mentira inocente, mentira deliberada, confabulação, pseudologia fantástica, hiperestimulação, contágio grupal e substituição de figura do agressor. Conclusão: A correta classificação das alegações de abuso sexual é importante tanto no campo clínico como no campo forênsico da psiquiatria. As definições neste artigo, são baseadas em experiências clínicas que deverão ser estudadas através de pesquisas sistemáticas. J.Am. Acad. Child Adoles. Psychiatry, 1993, 32, 5: 903-910.

Objective: Because child psychiatrists do not have a consistent way to classify the untruthful child and because there are no generally accepted definitions of the many ways in which false statements occur in allegations of abuse, the objective of this paper is to classify and define the various ways in which false statements occur in allegations of abuse. Method: the author reviewed 40 articles, chapters, and books that contained examples of false statements made by children or caregivers in the context of an abuse allegation. Results: this paper clarifies the concepts of indoctrination, suggestion, fantasy, delusion, misinterpretation, miscommunication, innocent lying, deliberate lying, confabulation, pseudologia phantastica, overstimulation, group contagion, and perpetrator substitution. Conclusion: the correct classification of abuse allegations is important in both clinical and forensic child psychiatry. The definitions in this paper, which are based on clinical experience, should be studied through systematic research.

Translation and adaptation of Eysenck personality questionnaire [Junior] and its validation with laborer adolescents

The present research aimed at translation, adaptation, and validation of the Eysenck Personality Questionnaire [Junior] [Eysenck and Eysenck, 1970] with laborer adolescents. After translation in first phase, sample of 60 adolescent students ranged from 13- 17 years [M-15.7]. was selected from Rawalpindi and Islamabad. The re-test reliability after 15 days determined the significant correlation coefficients for the all subscales of Urdu EPQ-[Junior], showing consistency of responses in the same language. In phase II Urdu EPQ [Junior] was administered on 200 male laborer adolescents with the age ranging 13- 17years [M= 15.39; SD= 1.55] from different areas of Rawalpindi/ Islamabad to establish the psychometric properties of the scale. The findings revealed satisfactory Cronbach 's alpha coefficients for all subscales of EPQ [Junior] Urdu and some significant findings with demographic variables as education

Incidencia de la mentira en la confianza y la cooperación en el ámbito laboral / The incidence of lies on trust and cooperation in the workplace

En este trabajo se analizan las repercusiones que conllevael uso de la mentira en entornos de trabajo. A partir delas valoraciones de los profesionales que trabajan en ellos, examinamos los efectos del objetivo y la tipicidad de la mentira sobre la valoración de su aceptabilidad, gravedad y de la percepción de sus consecuencias. Los resultados principales señalan que el objetivo por el cual se miente es el factor que más incide en la valoración social de este comportamiento y en la percepción de sus consecuencias en el entorno del trabajo, variando los efectos según el tipo de objetivo. Las mentiras que buscan el beneficio de otros son consideradas más aceptables, menos graves y dañan menos la confianza y la cooperación. Por el contrario, las mentiras que buscan el beneficio personal causando daño a otros son valoradas como más inaceptables y deterioran más los procesos de trabajo que requieren cooperación y confianza.

In this article we examine the repercussions that lying has in the workplace. The effects of the type of lie and the objectives for lying are explored through the measure of acceptability, graveness, and perception of the consequences based on evaluations made by professionals working there. The main results show that the objective behind the lying is the one which had a greater repercussion on social appraisal for the behaviour and on the perceptionof the consequences on the work environment, where the effects varied according to the type of objective. Lies that look for benefiting others are considered as more acceptable, less grave and harm both trust and collaboration to a lesser extent. On the contrary, lies that look for personal gain while causing harm to others are valued as more unacceptable and deteriorate those work processes requiring collaboration and trust.

Contando e detectando mentiras: efeito do feedback sobre o desempenho / Telling and detecting lies: the effect of feedback on performance

Estudos nos quais pessoas são testadas ao detectar mentiras mostram que a maioria da população parece ter essa habilidade pouco desenvolvida. O objetivo do presente trabalho foi avaliar o efeito do feedback dado após cada julgamento sobre a detecção de mentiras, com exposição prolongada à situação experimental, na qual detector e emissor interagiam frente a frente. Os resultados mostraram que o feedback levou a uma melhora do desempenho de todos os detectores, com porcentagens de acerto de até 100% em uma sessão. Contudo, o desempenho dos detectores mostrou pouca estabilidade e os dados sobre a generalização para outros emissores foram inconclusivos. Medidas independentes do comportamento dos emissores não revelaram diferenças consistentes entre verdades e mentiras, ainda que relatos pós-experimentais tenham apontado nessa direção. Foi discutida a importância de uma análise de dados individualizada e a necessidade de delineamentos que isolem a aprendizagem de detector e emissor.

Studies in which people are tested for detecting lies have shown that most of the population seems to have poorly developed lie-detection skills. The goal of this study was to assess the effect of feedback given after each judgment on lie detection, with extended exposure to an experimental situation in which detector and sender interacted face-to-face. Results showed that feedback led to performance improvement for all detectors, with accuracy rates up to 100% in a single session. However, detectors' performance showed little stability, and the data about generalization to other senders were inconclusive. Independent measures of senders' behavior didn't reveal consistent differences between truths and lies, even though post-experimental reports have pointed in this direction. The importance of an individualized data analysis and the need for experimental designs that isolate learning of detector and sender were discussed.

The development and application of lie detection in forensic science / 法医学杂志

Lie detection technology has been applied increasingly to investigate and solve criminal cases. This article explores the evolvement of lie detection technology in the ancient times and the application of the psychological and physiological parameters which have become more accurate with the introduction of modern polygraph. The cognitive exploration and the application of Event Related Potentials (ERPs), functional Magnetic Resonance Imaging (fMRI), and Event-Related functional Magnetic Resonance Imaging (E-R fMRI) have made detection technology focus on the brain activities, which produce more objective results by tracing the original state of lying. In summary, this article describes different types of lie detections, simple and complex, their working principles, the latest development, and the prospect of their application in forensic science.

Detection of malingering post-traumatic stress disorder / 法医学杂志

Assessment of post-traumatic stress disorder is a frequently encountered problem in forensic practices. Detection of malingering has become a focus in these assessments. While it is a difficult task due to kinds of traumatic events, complex clinical symptoms, subjective medical information, and presence of diverse psychotic disorders. The clinical traits, detecting methods and testing instruments of PTSD malingering were reviewed so as to help practical management and assessment.

An examination of the self-reported scale of brief psychopathological symptoms to detect malingering in forensic psychiatric subjects / 法医学杂志

OBJECTIVE@#To examine the self-reported scale of brief psychopathological symptoms (SBPS) to detect malingering in forensic psychiatric cases.@*METHODS@#Two hundred and six cases with different types of psychiatric problems were tested by SBPS. All cases were separately evaluated by two experts.@*RESULTS@#About 34.5% cases (71/206) were classified as malingering by the cut-off 13 scores of SBPS. Compared with expert's evaluation, SBPS showed a false negative rate of 19.8% and a false positive rate of 1.7%, respectively, with a total accuracy rate of 90.8%. Cases involved in compensations including working injury and traffic accidence showed the highest rate of malingering (51%).@*CONCLUSION@#SBPS is useful for detecting malingering psychopathological symptoms.