Deceptive Responses Research Articles

Are errors differentiable from deceptive responses when feigning memory impairment? An fMRI study

Previous neuroimaging studies have suggested that the neural activity associated with truthful recall, with false memory, and with feigned memory impairment are different from one another. Here, we report a functional magnetic resonance imaging (fMRI) study that addressed an important but yet unanswered question: Is the neural activity associated with intentional faked responses and with errors differentiable? Using a word list learning recognition paradigm, the findings of this mixed event-related fMRI study clearly indicated that the brain activity associated with intentional faked responses was different to the activity associated with errors committed unintentionally. For intentional faked responses, significant activation was found in the ventrolateral prefrontal cortex, the posterior cingulate region, and the precuneus. However, no significant activation was observed for unintentional errors. The results suggest that deception, in terms of feigning memory impairment, is not only more cognitively demanding than making unintentional errors but also utilizes different cognitive processes.

Neural Correlates of True Memory, False Memory, and Deception

We used functional magnetic resonance imaging (fMRI) to determine whether neural activity can differentiate between true memory, false memory, and deception. Subjects heard a series of semantically related words and were later asked to make a recognition judgment of old words, semantically related nonstudied words (lures for false recognition), and unrelated new words. They were also asked to make a deceptive response to half of the old and unrelated new words. There were 3 main findings. First, consistent with the notion that executive function supports deception, 2 types of deception (pretending to know and pretending not to know) recruited prefrontal activity. Second, consistent with the sensory reactivation hypothesis, the difference between true recognition and false recognition was found in the left temporoparietal regions probably engaged in the encoding of auditorily presented words. Third, the left prefrontal cortex was activated during pretending to know relative to correct rejection and false recognition, whereas the right anterior hippocampus was activated during false recognition relative to correct rejection and pretending to know. These findings indicate that fMRI can detect the difference in brain activity between deception and false memory despite the fact that subjects respond with “I know” to novel events in both processes.

Cerebral mechanisms of error detection during deceptive responses in the normal state and under the influence of alcohol

Event-related potentials (ERPs) were studied during deceptive and truthful responses of subjects that were in the normal state or under the influence of alcohol. The psychological task was designed in such a way that the subjects themselves decided whether or not they would tell a lie. Thirteen healthy volunteers participated in the study. An actual deceptive answer was characterized by a higher amplitude of the frontocentral ERP N190 component compared to the ERP accompanying a truthful answer. Alcohol consumption inverted the ratio between the amplitudes of this component in the cases of deceptive and truthful answers (with a higher amplitude in the latter case). The obtained result suggests that a deceptive action activates the so-called cerebral error detector. Under the influence of alcohol, the cerebral error detection system functioned abnormally, so that a deceptive action was not perceived as erroneous. This disturbance of automatic control may account for the lower amplitude of the late positive component of ERPs, which, in our opinion, reflects the process of making a decision on a deceptive response. This may explain why, e.g., alcohol consumption by a driver is hazardous: the activity is mainly controlled by conscious processes (the probability of making “the only right decision” in a critical situation is decreased, reactions become slow, etc.). Thus, the experimental model where the subject consumes a small amount of alcohol may be used for studying the altered functional mode of the cerebral error detector. Such studies seem promising in terms of searching for and developing methods for noninvasive modification of the error detector activity that could be used, e.g., in treatment for obsessions.

“Deception: Moral Transgression or Social Necessity?”: Cultural-Relativity of Deception Motivations and Perceptions of Deceptive Communication

In this study, we investigate the impact of cultural identity on: (a) motivations for engaging in deceptive communication, (b) the perceived “deceptiveness” of a range of deceptive responses, and (c) the willingness to use various deception strategies. Participants from three different locations (Hong Kong, Hawai'i, and mainland United States) were provided with a questionnaire designed to assess cultural identity, motivations for deception, perceptions of the deceptiveness of a range of various deceptive messages, and the willingness to use various available deception strategies. Results indicated that higher degrees of interdependence were related to a greater overall motivation to deceive for both self- and other-benefit. Furthermore, results suggest that whereas those characterized by higher degrees of independence will tend to perceive any message that departs from the truth as highly deceptive in nature, those characterized by higher degrees of interdependence will be more likely to perceive messages that depart from truth as “not deceptive.” Finally, the willingness to use the various deception strategies was found to be moderated by effects of the self-benefit versus other-benefit situations. Current findings provide preliminary evidence that culture is indeed a relevant factor that can no longer be ignored in future theorizing and investigation of deceptive communication phenomena.

Stages of the cerebral mechanisms of deceptive responses

Cerebral mechanisms of perceiving and telling lies were studied by recording event-related potentials (ERPs) both after an actual deceptive response and during the time interval when the subject decided to tell a lie. Ten healthy volunteers participated in the study. The test consisted of their playing a game against a computer. The subjects could choose between deceptive and truthful answers so as to win the game. The subjects gave a deceptive answer intentionally, the structure of the test ensuring equal numbers of deceptive and truthful answers. The relaxation times in the cases of truthful and deceptive answers did not differ significantly from each other. The comparison of ERPs accompanying deceptive and truthful answers showed the existence of a negativity with a latent period of 90 ms in the regions of the right frontal, central, and right parietal derivations. This negativity indicated that the brain reacted to a deceptive answer even if this a priori “erroneous” act ensured reaching the goal and, in this sense, was subjectively relevant. In terms of the cerebral error detector mechanism, this phenomenon may be regarded as a special case of a general response of the brain to giving an incorrect (deceptive) answer, rather than a response to a lie per se. The interval of time when, presumably, the decision on a deceptive answer was being made was found to contain the late positive component P540, which is most likely to be involved in the preparation of the deceptive answer and the intention to tell a lie.

The self in conflict: The role of executive processes during truthful and deceptive responses about attitudes

This study sought to extend previous results regarding deceptions about specific memories by investigating the role of executive processes in deceptions about evaluative judgments. In addition, given that previous studies of deception have not included valence manipulations, we also wanted to determine whether the goodness/badness aspect of the items would affect the processes used during deception. Thus, we compared behavioral and event-related potential (ERP) activity while participants made truthful and directed lie (i.e., press opposite of the truth) responses about attitude items with which they either strongly agreed or disagreed. Consistent with previous results, deceptive responses required greater cognitive control as indicated by slower RTs, larger medial frontal negativities (MFN) and smaller late positive components than truthful responses. Furthermore, the magnitude of these deception-related effects was dependent on the valence that participants assigned to the items (i.e., agree/disagree). Directed lie responses about attitudes also resulted in greatly reduced pre-response positivities, an indication that participants strategically monitored their responses even in the absence of explicit task demands. Item valence also differentially affected the amplitude of three ERP components in a 650 ms pre-response interval, independently of whether truthful or deceptive responses were made. Analyses using dipole locations based on results from fMRI studies of evaluative judgments and deception indicated a high degree of overlap between the ERP and fMRI results and revealed the possible temporal characteristics of the hemodynamic activations.

Lie-Specific Involvement of Dorsolateral Prefrontal Cortex in Deception

Lies are intentional distortions of event knowledge. No experimental data are available on manipulating lying processes. To address this issue, we stimulated the dorsolateral prefrontal cortex (DLPFC) using transcranial direct current stimulation (tDCS). Fifteen healthy volunteers were tested before and after tDCS (anodal, cathodal, and sham). Two types of truthful (truthful selected: TS; truthful unselected: TU) and deceptive (lie selected: LS; lie unselected: LU) responses were evaluated using a computer-controlled task. Reaction times (RTs) and accuracy were collected and used as dependent variables. In the baseline task, the RT was significantly longer for lie responses than for true responses ([mean +/- standard error] 1153.4 +/- 42.0 ms vs. 1039.6 +/- 36.6 ms; F(1,14) = 27.25, P = 0.00013). At baseline, RT for selected pictures was significantly shorter than RT for unselected pictures (1051.26 +/- 39.0 ms vs. 1141.76 +/- 41.1 ms; F(1,14) = 34.85, P = 0.00004). Whereas after cathodal and sham stimulation, lie responses remained unchanged (cathodal 5.26 +/- 2.7%; sham 5.66 +/- 3.6%), after anodal tDCS, RTs significantly increased but did so only for LS responses (16.86 +/- 5.0%; P = 0.002). These findings show that manipulation of brain function with DLPFC tDCS specifically influences experimental deception and that distinctive neural mechanisms underlie different types of lies.

Effects of Preparedness to Deceive on ERP Waveforms in a Two-Stimulus Paradigm

SUMMARY Stimulus salience, attentional capture, and working memory load have all been theoretically and experimentally linked to deception (Allen & Iacono, 1997; Boaz, Perry, Raney, Fischler, & Shuman, 1991; Dionisio, Granholm, Hillix, & Perrine, 2001; Stelmack, Houlihan, & Doucet, 1994). This study manipulated working memory load by truthful and deceptive response demands combined with congruent and incongruent response demands. Response demands were randomly presented across trials requiring attention shifting within each trial, and preparedness to deceive was systematically decreased across three experiments. Four waveforms were examined: an N2b occurring at 150–250 ms with an anterior maximum, a P3a occurring at 250–450 ms with an anterior maximum, an N4 occurring at 300–500 ms with an anterior and temporal maximum, and a P3b occurring at 500–700 ms with a parietal maximum. Results suggest that the processes of stimulus salience, attention shifting and resource allocation, long-term memory, and contex...

Single-trial discrimination of truthful from deceptive responses during a game of financial risk using alpha-band MEG signals

We studied whether magnetoencephalography (MEG) could detect deceptive responses on a single-subject, trial-by-trial basis. To elicit spontaneous, ecologically valid deception, we developed a paradigm in which subjects in a simulated customs setting were presented with a series of pictures of items which might be in their baggage, and for each item, they decided whether to ‘declare’ (tell the truth) or ‘smuggle’ (lie). Telling the truth involved a small but certain monetary penalty, whereas lying involved both greater monetary risk and greater potential reward. Most subjects showed decreased signal power in the 8–12 Hz (alpha) range during deceptive responses as compared to truthful responses. In a cross-validation analysis, we were able to use alpha power to classify truthful and deceptive responses on a trial-by-trial basis, with significantly greater predictive accuracy than that achieved using simultaneously recorded skin conductance signals. Average predictive accuracy for spontaneous deception was greater than 78%, and for some subjects, predictive accuracy exceeded 90%. Our results raise the possibility that alpha power modulation during deception may reflect risk management and/or cognitive control.

Deceptive responses: The impact of verbal and non‐verbal countermeasures

Objectives. This experiment investigates the impact of informing participants about verbal and non‐verbal cues to deception on their verbal and non‐verbal responses. Based on the fact that people are more practised in their verbal behaviour than in their non‐verbal behaviour, we predicted that giving participants information about verbal cues would positively affect their verbal accounts resulting in them giving an account that appeared more credible. In contrast, we predicted that informing participants about non‐verbal cues would have no noticeable effect on credibility. We also predicted that focusing on verbal behaviours would impair non‐verbal performance and that, vice versa, concentrating on non‐verbal behaviours would impair verbal performance, particularly in liars.Method. A total of 128 participants either told the truth or lied about the possession of an object. Prior to these interviews, participants were or were not informed about verbal cues to deception and were or were not informed about non‐verbal cues of deception (these two factors were systematically manipulated).Results. As predicted, participants were able to adapt their verbal behaviour but were not able to change their non‐verbal behaviour. However, focusing on one aspect (either verbal or non‐verbal behaviour) did not occur at the expense of the other behaviour (either non‐verbal or verbal).Conclusion. Verbal countermeasures may well be easier to apply than non‐verbal countermeasures.

Leuprolide Acetate Suppresses Pedophilic Urges and Arousability

Cognitive-behavioral psychotherapy was compared with cognitive-behavioral psychotherapy augmented by leuprolide acetate (LA) for suppression of pedophilic behavior. Five male pedophiles (M age, 50 years; range, 36-58) were administered LA by Depo injection for 12 months, followed by saline placebo for 12 months. Testosterone levels, sexual interest preference by visual reaction time (Abel Assessment), penile tumescence (Monarch Penile Plethysmography, PPG), as well as strong sexual urges toward children and masturbatory frequency involving thoughts of children (polygraph), were measured every 3 months. On LA, testosterone decreased to castrate levels. Penile tumescence was significantly suppressed compared with baseline, but sufficient response remained to detect pedophilic interest. Pedophilic interest was also detected by visual reaction times. When asked about having pedophilic urges and masturbating to thoughts of children, all subjects self-reported a decrease. Polygraph responses indicated subjects were not deceptive. On placebo, testosterone and physiologic arousal eventually rose to baseline. As noted by polygraph, at baseline and on placebo, subjects were deceptive regarding increased pedophilic urges and masturbatory frequency. Interest preference, as measured by Abel Assessment and Monarch PPG, was generally unchanged throughout the study. Cognitive-behavioral psychotherapy augmented with LA significantly reduced pedophilic fantasies, urges, and masturbation; however, pedophilic interest did not change during 1 year of therapy. Deceptive responses by polygraph suggested that self-report was unreliable. Follow-up utilizing objective measures is essential for monitoring efficacy of treatment in pedophilia. Our study supports the premise that suppression of pedophilic behavior is possible. LA may augment cognitive-behavioral psychotherapy and help break the sequence leading to a re-offense.

Detecting Deception Using Functional Magnetic Resonance Imaging

The ability to accurately detect deception is presently very limited. Detecting deception might be more accurately achieved by measuring the brain correlates of lying in an individual. In addition, a method to investigate the neurocircuitry of deception might provide a unique opportunity to test the neurocircuitry of persons in whom deception is a prominent component (i.e., conduct disorder, antisocial personality disorder, etc.). In this study, we used functional magnetic resonance imaging (fMRI) to show that specific regions were reproducibly activated when subjects deceived. Subjects participated in a mock crime stealing either a ring or a watch. While undergoing an fMRI, the subjects denied taking either object, thus telling the truth with some responses, and lying with others. A Model-Building Group (MBG, n = 30) was used to develop the analysis methods, and the methods were subsequently applied to an independent Model-Testing Group (MTG, n = 31). We were able to correctly differentiate truthful from deceptive responses, correctly identifying the object stolen, for 93% of the subjects in the MBG and 90% of the subjects in the MTG. This is the first study to use fMRI to detect deception at the individual level. Further work is required to determine how well this technology will work in different settings and populations.

Differential effects of practice on the executive processes used for truthful and deceptive responses: An event-related brain potential study

Behavior and event-related potentials (ERP) were recorded while participants made truthful and deceptive responses about previously memorized words under three instructional conditions: consistent truthful, consistent deceptive, and random deceptive. To determine if practice affected the deception-related activity we reported previously [R. Johnson, Jr., J. Barnhardt, J. Zhu, The deceptive response: effects of response conflict and strategic monitoring on the late positive component and episodic memory-related brain activity. Biol. Psychol., 64 (2003) 217–253; R. Johnson, Jr., J. Barnhardt, J. Zhu, The contribution of executive processes to deceptive responding. Neuropsychologia, 42 (2004) 878–901], participants performed two blocks of 145 trials of each condition. In the consistent truthful condition, practice benefited performance as indicated by decreased reaction time (RT) and RT variability. In addition, practice increased P300 amplitude and decreased the amplitude of a medial frontal negativity (MFN), which is believed to index the use of response-monitoring processes. However, a different pattern of results obtained in the two deception conditions. Although practice decreased RTs by almost as much as in the consistent truthful condition, the extent to which deceptive response in both conditions were slower than those in the consistent truthful condition actually increased slightly. Hence, the component of RT reflecting processing of conflicting response information did not decrease. In accord with the RT results, MFN amplitudes in the consistent deceptive and random deceptive conditions were unaffected by practice, suggesting that the amount of executive processes required to make and/or monitor deceptive responses was undiminished by practice. Although P300 amplitude increased slightly in the consistent deceptive condition, there was no change in the random deceptive condition. Thus, a major finding here is that, unlike truthful responses, the conceptually driven response conflicts underlying deceptive responses appear to be as resistant to practice-induced changes as described previously for perceptually driven response conflicts.

Neural correlates of telling lies: A functional magnetic resonance imaging study at 4 Tesla 1

Intentional deception (ie, lying) is a complex cognitive act, with important legal, moral, political, and economic implications. Prior studies have identified activation of discrete anterior frontal regions, such as the ventrolateral prefrontal cortex (VLPFC), dorsolateral prefrontal cortex (DLPFC), dorsal medial prefrontal cortex (DMPFC), and anterior cingulate cortex (ACC) during deception. To extend these findings, we used novel real-time functional magnetic resonance imaging (fMRI) technology to simulate a polygraph experience in order to evoke performance anxiety about generating lies, and sought to ascertain the neural correlates of deception. In this investigational fMRI study done with a 4-T scanner, we examined the neural correlates of lying in 14 healthy adult volunteers while they performed a modified card version of the Guilty Knowledge Test (GKT), with the understanding that their brain activity was being monitored in real time by the investigators conducting the study. The volunteers were instructed to attempt to generate Lies that would not evoke changes in their brain activity, and were told that their performance and brain responses were being closely monitored. Subjects reported performance anxiety during the task. Deceptive responses were specifically associated with activation of the VLPFC, DLPFC, DMPFC, and superior temporal sulcus. These findings suggest the involvement of discrete regions of the frontal cortex during lying, and that the neural substrates responsible for cognitive control of behavior may also be engaged during deception.

Reaction Time of Motor Responses in Two-Stimulus Paradigms Involving Deception and Congruity with Varying Levels of Difficulty

Deception research has focused on identifying peripheral nervous system markers while ignoring cognitive mechanisms underlying those markers. Cognitive theorists argue that the process of deception may involve such constructs as attentional capture, working memory load, or perceived incongruity with memory, while psychophysiologists argue for stimulus salience, arousal, and emotion. Three studies were conducted to assess reaction time (RT) in relation to deception, response congruity, and preparedness to deceive. Similar to a semantic verification task, participants evaluated sentences that were either true or false, and then made truthful or deceptive evaluations of the sentence’s base truth-value. Findings indicate that deceptive responses have a longer RT than truthful responses, and that this relationship remains constant across response type and preparedness to deceive. The authors use these findings in preliminary support of a comprehensive cognitive model of deception.

Diagnosing estimate distortion due to significance testing in literature on detection of deception.

Studies journals typically report or feature results significant by statistical test criterion. This is a bias that prevents obtaining precise estimates of the magnitude of any underlying effect. It is severe with small effect sizes and small numbers of measurements. To illustrate the problem and a diagnosis technique, results of published studies on the detection of deception are graphed. The literature contains large effect sizes affirming that deceptive responses in contrast to truthful responses are associated with more reactive Skin Resistance Responses. These effect sizes when graphed on the x-axis against n on the y-axis are distributed as funnel graphs. A subset of studies show support for predicted small to medium effects on different physiological measures, individual differences, and condition manipulations. These effect sizes graphed by sample ns follow negative correlations, suggesting that effect sizes from published values of t, F, and zeta are exaggerations.

The contribution of executive processes to deceptive responding

We measured behavioral responses (RT) and recorded event-related brain potentials (ERPs) when participants made truthful and deceptive responses about perceived and remembered stimuli. Participants performed an old/new recognition test under three instructional conditions: Consistent Truthful, Consistent Deceptive and Random Deceptive. Compared to Consistent Truthful responses, Consistent Deceptive responses to both perceived and remembered stimuli produced the same pattern of less accurate, slower and more variable responses and larger medial frontal negativities (MFN). The MFN is thought to reflect activity in anterior cingulate cortex, a brain area involved in monitoring actions and resolving conflicting response tendencies. The Random Deceptive condition required participants to strategically monitor their long-term response patterns to accommodate a deceptive strategy. Even compared to the Consistent Deceptive condition, RTs in the Random Deceptive condition were significantly slower and more variable and MFN activity increased significantly. MFN scalp distribution results revealed the presence of three different patterns of brain activity; one each for truthful responses, deceptive responses and strategic monitoring. Thus, the data indicate that anterior cingulate cortex plays a key role in making deceptive responses.

Response-Specific Scalp Distributions in Deception Detection and ERP Correlates of Psychopathic Personality Traits

Abstract University students were screened using items from the Psychopathic Personality Inventory and divided into high (n = 13) and low (n = 11) Psychopathic Personality Trait (PPT) groups. The P300 component of the event-related potential (ERP) was recorded as each group completed a two-block autobiographical oddball task, responding honestly during the first (Phone) block, in which oddball items were participants' home phone numbers, and then feigning amnesia in response to approximately 50% of items in the second (Birthday) block in which oddball items were participants' birthdates. Bootstrapping of peak-to-peak amplitudes correctly identified 100% of low PPT and 92% of high PPT participants as having intact recognition. Both groups demonstrated malingering-related P300 amplitude reduction. For the first time, P300 amplitude and topography differences were observed between honest and deceptive responses to Birthday items. No main between-group P300 effects resulted. Post-hoc analysis revealed between-group differences in a frontally located post-P300 component. Honest responses were associated with late frontal amplitudes larger than deceptive responses at frontal sites in the low PPT group only.

The deceptive response: effects of response conflict and strategic monitoring on the late positive component and episodic memory-related brain activity

The cognitive processes and neural mechanisms underlying deceptive responses were studied using behavioral responses (RT) and event-related brain potentials (ERPs) while participants made truthful and deceptive responses about perceived and remembered stimuli. Memorized words were presented in a recognition paradigm under three instructional conditions: Consistent Truthful, Consistent Deceptive, Random Deceptive. Responses that conflicted with the truth about both perceived and remembered items produced the same pattern of slower RTs and decreased LPC amplitudes. When long-term response patterns were monitored, RTs became much slower and LPC amplitudes decreased greatly. The different behavioral and ERP changes in the two deception conditions suggested that two dissociable executive control processes, each requiring additional processing resources, can contribute to deceptive responses. The parietal episodic memory (EM) effect, thought to reflect recollection, was unaffected by whether participants responded truthfully or deceptively suggesting that it provides a measure of guilty knowledge.

Lie detection with contingent negative variation

Topographies of contingent negative variation (CNV) were recorded in a paradigm of delayed response with feedback for three kinds of faces: familiar, strange and target. Subjects made responses to the faces according to whether the faces were familiar or not, but also, gave deliberately deceptive responses to target faces to ‘cheat the computer’. Subjects were told that the computer could judge whether they were being honest or not. For each trial of the experiment, if subjects cheated the computer successfully and their responses were judged as honest and they were given a reward, otherwise they received a penalty. In this simulated lie detection test, CNV exhibited more negative shifts for target than those for non-target (familiar and strange). These differences could be accounted for by subjects’ motivation and uncertainty about passing the test. With the results of further paired t-tests between target and non-target faces at each electrode, CNV was demonstrated as a reliable indicator for lie detection. In addition, vector length was used to capture global CNV information and was found to be a very good indicator, even better than the CNV information at the individual electrode sites.