Objective measurement of patient's dental anxiety by galvanic skin reaction

The purpose of this study was to determine if anxiety can be measured objectively by skin conductance of a weak electric current. Three measurements were taken. First, a standardized dental-anxiety questionnaire was given to determine anxiety. Second, galvanic skin conductance was measured. Third, polygraph responses were recorded to three key questions from the questionnaire. Questionnaire scores of these key questions were used to create two groups: anxious and not-anxious. The three key questions were subjected to polygraph verification. In the first analysis patients were excluded if the polygraph test disclosed lying on any of the three key questions. The second analysis excluded liars on a question-by-question basis. The third analysis disregarded the polygraph. A statistically significant correlation was found between skin conductance and dental anxiety in all cases. Data seem to indicate that fear of injection is the most anxiety-producing aspect of modern dentistry.

Facial appearance and judgments of credibility: the effects of facial babyishness and age on statement credibility

Researchers have found that facial appearance influences social judgments. For example, evidence has shown that facial babyishness and age affect perceivers' impressions of the stimulus person's veracity. In this experiment, the researchers examined whether these variables also influenced the credibility attributed to written statements purportedly made by these people in addition to several topics of interest in deception-detection research. Undergraduates (N = 270) were presented babyfaced or mature-faced photographs that depicted a child, an adult, or an older individual, in addition to a written truthful or deceptive statement purportedly made by the person in the photograph. Results showed that, as predicted, when the statements were accompanied by babyfaced pictures, participants tended to judge them as truthful, but only if the pictures did not depict children. Also, when the statements were accompanied by childen's pictures, participants tended to judge them as deceptive, but only if the pictures depicted a babyish face. Overall detection accuracy was close to chance and did not correlate with either judgmental confidence or with the respondents' estimated lie-detection accuracy. However, confidence and estimated ability were significantly correlated. Also, more confidence was placed in judgments of truthfulness than in judgments of deceptiveness. Respondents' truth bias and the existence of a veracity effect in the diverse experimental conditions were examined as well.

Children's use of gaze and limb movement cues to infer deception

A sample of 96 children from kindergarten, 2nd, 4th, and 6th grades judged the truthfulness of peers who varied in gaze and limb movement while providing verbal communications. Results indicated that children attributed greater lying to the peers who displayed indirect rather than direct gaze and active rather than nonactive limb movement. The use of these cues was more evident in 4th- and 6th-grade children than it was in kindergarten and 2nd-grade children. Pilot studies indicated that adults and children as young as 5-6 years of age associated indirect gaze and active limb movement with anxiety. The findings are discussed with respect to children's theory of mind, concepts of lying, understanding of display rules, and learning of physiological cues associated with deception.

The validity of psychophysiological detection of information with the Guilty Knowledge Test: a meta-analytic review

The authors performed a meta-analysis based on 169 conditions, gathered from 80 laboratory studies, to estimate the validity of the Guilty Knowledge Test (GKT) with the electrodermal measure. The overall average effect size was 1.55, but there were considerable variations among studies. In particular, mock-crime studies produced the highest average effect size (2.09). Three additional moderators were identified: Motivational instructions, deceptive ("no") verbal responses, and the use of at least 5 questions were associated with enhanced validity. Finally, a set of 10 studies that best approximated applications of the GKT under optimal conditions produced an average effect size of 3.12. The authors discuss factors that might limit the generalizability of these results and recommend further research of the GKT in realistic setups.

The current role of post-conviction sex offender polygraph testing in sex offender treatment

Polygraph testing is becoming increasingly important in sex offender treatment. Polygraph advocates cite dramatic increases in historical disclosures that presumably allow more precise targeting of treatment interventions, earlier detection of risky behaviors that often lead to new offenses, and improved treatment and supervision compliance. Based on this, they believe the procedure supports desirable behavior that continues to various degrees after treatment and supervision end. Opponents cite ethical problems related to inaccurate results, unproven accuracy rates, and the risk that examinees may be coerced into making false admissions. To counter these criticisms, proponents have developed standards, best practices, and examiner training and certification programs intended to reduce error rates and address ethical issues. Opponents argue that these measures have not been tested and that empirically established error rates and best practices may not be possible for a variety of reasons. This article reviews the current situation, leaving readers to decide the wisdom and ethics of using polygraph testing in their own practices.

The origin of conditional logic: does a cheater detection module exist?

The domain-specific hypothesis of L. Cosmides (1989) and L. Cosmides and J. Tooby (1989, 1992) positing that conditional logic has its origin in the evolution of social exchange and in the detection of potential cheaters was tested against a more domain-general hypothesis positing that adult reasoning is logical and that errors in conditional reasoning arise from misunderstandings, not from a lack of logicality. The results of 5 experiments with undergraduate students (n = 682 for Experiments 1-4; n = 188 for Experiment 5), which involved a series of selection tasks that yielded specific predictions about participant performance, were not consistent with the cheater detection hypothesis. Findings supported the misunderstandings hypothesis and imply that adults possess general-purpose logical competence versus domain-specific modules.

The influence of individual versus aggregate social comparison and the presence of others on self-evaluations

In 5 studies, the authors investigated the effects of comparison with an individual versus comparison with the statistical average on self-evaluations of performance and ability. In Studies 1 and 2, participants took a test of lie detection ability and were provided with the average score and the score of an individual coactor. Both types of feedback significantly affected self-evaluations of performance, but only comparison with the coactor significantly affected self-evaluations of ability. Studies 3 and 4 demonstrated that the presence of a coactor moderated the effect of aggregate social comparison on self-evaluations of ability. The results provide preliminary support for the contention that minimizing the impact of comparison with the average is a self-serving strategy that is facilitated by the presence of others.

Trial by polygraph: reconsidering the use of the guilty knowledge technique in court

Polygraph test results are by and large ruled inadmissible evidence in criminal courts in the US, Canada, and Israel. This is well-conceived with regard to the dominant technique of polygraph interrogation, known as the Control Question Technique (CQT), because it indeed does not meet the required standards for admissible scientific evidence. However, a lesser known and rarely practiced technique, known as the Guilty Knowledge Test (GKT), is capable, if carefully administered, of meeting the recently set Daubert criteria. This paper describes the technique, and argues for considering its admissibility as evidence in criminal courts.

Will the truth come out? the effect of deception, age, status, coaching, and social skills on CBCA scores

The impact of Veracity, Age, Status (witness or suspect), Coaching (informed or uninformed regarding CBCA), and Social Skills (social anxiety, social adroitness, and self-monitoring) on Criteria-Based Content Analysis scores was examined. Participants (aged 5-6, 10-11, 14-15, and undergraduates) participated in a "rubbing the blackboard" event. In a subsequent interview they told the truth or lied about the event. They were accused of having rubbed the blackboard themselves (suspect condition) or were thought to have witnessed the event (witness condition), and were or were not taught some CBCA criteria prior to the interview. CBCA scores discriminated between liars and truth tellers in children, adults, witnesses, and suspects. However, truth tellers obtained higher CBCA scores than liars only when the liars were uninformed about CBCA. CBCA scores were correlated with social skills. It is argued that thesefindings should caution those who believe that the validity of CBCA has been conclusively demonstrated.

Brain activity during simulated deception: an event-related functional magnetic resonance study

TheGuilty Knowledge Test (GKT) has been used extensively to model deception. An association between the brain evoked response potentials and lying on the GKT suggests that deception may be associated with changes in other measures of brain activity such as regional blood flow that could be anatomically localized with event-related functional magnetic resonance imaging (fMRI). Blood oxygenation level-dependent fMRI contrasts between deceptive and truthful responses were measured with a 4 Tesla scanner in 18 participants performing the GKT and analyzed using statistical parametric mapping. Increased activity in the anterior cingulate cortex (ACC), the superior frontal gyrus (SFG), and the left premotor, motor, and anterior parietal cortex was specifically associated with deceptive responses. The results indicate that: (a) cognitive differences between deception and truth have neural correlates detectable by fMRI, (b) inhibition of the truthful response may be a basic component of intentional deception, and (c) ACC and SFG are components of the basic neural circuitry for deception.

Effects of the testing situation on item responding: cause for concern

The effects of faking on personality test scores have been studied previously by comparing (a) experimental groups instructed to fake or answer honestly, (b) subgroups created from a single sample of applicants or nonapplicants by using impression management scores, and (c) job applicants and nonapplicants. In this investigation, the latter 2 methods were used to study the effects of faking on the functioning of the items and scales of the Sixteen Personality Factor Questionnaire. A variety of item response theory methods were used to detect differential item/test functioning, interpreted as evidence of faking. The presence of differential item/test functioning across testing situations suggests that faking adversely affects the construct validity of personality scales and that it is problematic to study faking by comparing groups defined by impression management scores.

The frontal lobes are necessary for 'theory of mind'

Patients with limited focal frontal and nonfrontal lesions were tested for visual perspective taking and detecting deception. Frontal lobe lesions impaired the ability to infer mental states in others, with dissociation of performance within the frontal lobes. Lesions throughout the frontal lobe, with some suggestion of a more important role for the right frontal lobe, were associated with impaired visual perspective taking. Medial frontal lesions, particularly right ventral, impaired detection of deception. The former may require cognitive processes of the lateral and superior medial frontal regions, the latter affective connections of the ventral medial frontal with amygdala and other limbic regions.

Using brain MERMER testing to detect knowledge despite efforts to conceal

This experiment examined the accuracy and reliability of the memory and encoding related multifaceted electroencephalographic response (MERMER) technique for detecting information related to events subjects have experienced, despite subjects' efforts to conceal that knowledge. Information obtained through interviews was used to develop stimulus sets consisting of words and phrases presented to subjects visually by computer. Sets were composed of three types of stimuli: life experience-related (Probes), stimuli the subject was asked to memorize and respond to (Targets), and irrelevant information (Irrelevants). Each set of stimuli was tested on two individuals: (1) one individual who had participated in the event in question--and thus had the relevant information stored in his/her brain, and (2) one who had not. Six subjects were tested. Electrical brain responses to the stimuli were recorded non-invasively from the scalp and analyzed. MERMERs, (memory and encoding related multifaceted electroencephalographic responses), of which the P300 is a sub-component, were used to determine whether the subject had the relevant information stored in his brain (information present) or not (information absent), thus indicating whether or not each subject had participated in the real-life event in question. Bootstrapping was used to analyze and compare the responses to the three types of stimuli. As predicted, MERMERs were elicited by Probe stimuli only in the subjects who had participated in the investigated event, by Target stimuli in all subjects, and in no case by Irrelevant stimuli. For each of the six subjects, brain MERMER testing correctly determined whether the subject had participated in and consequently knew about the event in question (information present) or had not participated (information absent). The statistical confidence for this determination was 99.9% in five cases and 90.0% in one case. The article concludes with a discussion of areas of future research and the potential for using this new technology as an investigative tool in criminal cases.

Truth, lies, and videotape: an investigation of the ability of federal parole officers to detect deception

The ability of a group of Canadian federal parole officers to detect deception was investigated over the course of 2 days of lie detection training. On the first day of training, 32 officers judged the honesty of 12 (6 true, 6 fabricated) videotaped speakers describing personal experiences, half of which were judged before and half judged after training. On the second day, 5 weeks later, 20 of the original participants judged the honesty of another 12 videotapes (again, 6 pre- and 6 posttraining). To isolate factors relating to detection accuracy, three groups of undergraduate participants made judgments on the same 24 videotapes: (1) a feedback group, which received feedback on accuracy following each judgment, (2) a feedback + cue information group, which was given feedback and information on empirically based cues to deception, and (3) a control group, which did not receive feedback or cue information. Results indicated that at baseline all groups performed at or below chance levels. However, overall, all experimental groups (including the parole officers) became significantly better at detecting deception than the control group. By the final set of judgments, the parole officers were significantly more accurate (M = 76.7%) than their baseline performance (M = 40.4%) as well as significantly more accurate than the control group (M = 62.5%). The results indicate that detecting deceit is difficult, but training and feedback can enhance detection skills.

The impact of polygraphy on admissions of victims and offenses in adult sexual offenders

Sexual offenders are extremely reluctant to disclose their offending histories for a variety of psychosocial and legal reasons. The polygraph has shown promise as a intervention for eliciting admissions of past sexual offending behaviors. For 60 adult male sexual offender (35 inmates and 25 parolees), the number of victims and offenses were recorded from the Presentence Investigative Report, Sexual History Disclosure form, and 2 consecutive polygraph examination reports. Dramatic increases in the number of admitted victims and offenses were found for inmates, but not for parolees, across each source. However, there was a substantial decline in the number of victim and offense admissions by the second polygraph examination for both groups, even though 80% of the examination results reveled deception about sexual offending behaviors. Standardized use of sanctions and privileges for deceptive and nondeceptive polygraph results, respectively, are proposed as a way of eliciting full disclosure of offending histories for these offenders.

Allegations of wrongdoing: the effects of reinforcement on children's mundane and fantastic claims

S. Garven, J. M. Wood, R. S. Malpass, and J. S. Shaw (1998) found that the interviewing techniques used in the McMartin Preschool case can induce preschool children to make false allegations of wrong doing against a classroom visitor. In this study, 2 specific components of the McMartin interviews, reinforcement and cowitness information, were examined more closely in interviews of 120 children, ages 5 to 7 years. Children who received reinforcement made 35% false allegations against a classroom visitor, compared with 12% made by controls. When questioned about "fantastic" events (e.g., being taken from school in a helicopter), children receiving reinforcement made 52% false allegations, compared with 5% made by controls. In a second interview, children repeated the allegations even when reinforcement had been discontinued. The findings indicate that reinforcement can swiftly induce children to make persistent false allegations of wrong doing.

Using response time measures to assess "guilty knowledge"

How can a suspect's guilt or innocence be reliably tested? The validity of the polygraph, which measures changes in physiological arousal during a "guilty knowledge" test, is controversial (e.g., T. R. Bashore & P. E. Rapp, 1993; T. P. Cross & L. Saxe, 1992; D. T. Lykken, 1998; J. P. Rosenfeld, 1995; R. Steinbrook, 1992). One alternative to the polygraph examines event-related potentials recorded during a memory interference task (L. A. Farwell & E. Donchin, 1991). The present study extended this paradigm to determine whether response times (RTs) can accurately identify participants possessing specific guilty knowledge. Results from Experiment 1 showed that RT alone can reliably discriminate "guilty" from "innocent" participants. Experiments 2a and 2b indicated that an RT-based paradigm is more resistant to strategic manipulation than previously suggested (Farwell & Donchin, 1991). This RT-based paradigm may be a viable alternative to the polygraph for detecting guilty knowledge.

Current issues in the diagnosis and management of malingering

Malingering is a diagnosis that is frequently avoided by physicians. When there is a claim of symptoms or diseases that either are exaggerated or do not exist, the diagnosis of malingering should be entertained. Malingering is associated with a conscious intent to deceive in order to obtain a known gain. Psychoanalytical, criteria-based (DSM-IV) and 'adaptational' models have been advanced to explain malingering. The differential diagnosis of malingering includes factitious disorder, the somatoform disorders, the dissociative disorders, and specific medical conditions without somatoform disorder. Upon consideration of the differential diagnosis, confirmation of the suspicion of malingering is still required in order to make the diagnosis. Confirmation can be achieved by observation or by inferential methods. Observation can be employed with controlled environment observation or with covert, 'real-world' surveillance; inference may involve primary and/or secondary source information. It may be concluded that a greater attempt should be made to identify this diagnosis, as the cost of malingering to society is considerable.

Rape: medical and legal information

The author explores the topic of rape in order to help security directors and rape victims better understand the medical and legal procedures a victim might experience. He describes how a rape case might be handled and what to expect.