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However, a third group of informed innocent participants who had merely been notified of details regarding the murder also showed a distinct response upon the presentation of the critical detail. While the CIT is an established method to verify whether an individual possesses critical knowledge, it does not pinpoint the source of this information. While retaining the main elements of the CIT, rather than probing for passive knowledge about the crime e.
Which vehicle was used to flee from the crime scene? How did you flee from the scene? Contrary to the CIT, informed innocents recognizing the correct answer could now remain truthful while denying knowledge of the correct option. However, a more recent direct comparison of the two methods to detect concealed information revealed that similar to the CIT, the GAT could not accurately distinguish between participants who committed the mock crime and innocent participants who were informed about its details Gamer, In Japan, where the CIT is applied in criminal investigations on a large scale Osugi, , the leakage problem is often tackled by formulating questions at the exemplar level.
The crux is to ask for more specific information that is less likely to be leaked to the general public, such as the brand of the getaway vehicle. At the same time, asking such specific questions raises new challenges for the CIT regarding the balance between false-positive and false-negative outcomes. A first challenge concerns lack of memory for exemplar details.
Examiners have to estimate what the perpetrator experienced during the robbery and choose specific details such that there is great likelihood that a guilty suspect would have noticed them, stored them in memory, and remembers it at the time of the CIT. A second challenge concerns item distinguishability, referring to the fact that items at an exemplar level may be less discernable from the alternative fillers than items at a broader category level Osugi, Probing exemplar-level critical details in a multiple-choice format requires homogeneously matched control alternatives in the CIT.
Since items at the exemplar level are more similar than a set of words at the category level, because they share the same category, this may diminish the capacity of the critical detail to pop-out among the other alternatives Donchin, ; Sokolov, As the perpetrator was presented within a series of matched foil faces that very well resembled the culprit, the cooperative eyewitnesses did not show the automatic, differential response pattern to the critical face. Hence, stimulus distinctiveness seems to be an important factor for successful memory detection.
Likewise, validity of memory detection is lowered when the items in the CIT slightly differ from the encoded information in modality, category or semantics. Thus, while asking specific questions may help to reduce the risk of false positives associated with the leakage of crime information, it may increase the risk of false negatives due to reduced memory and limited distinguishability between the critical and control items, which may lead to decreased responsivity to the critical item.
In the present study, we further expand existing research on this issue that has both theoretical and practical implications, by investigating what would be the optimal question format for the CIT. While Ben-Shakhar et al.
Besides testing the optimal level of abstractness for CIT questioning, this allows to investigate whether the CIT detection efficiency depends on the level of abstractness during encoding. Participant couples were involved in the planning phase of a mock robbery of a bank, with the critical items encoded either at the category e. One participant of the pair was asked to immediately participate in a deception detection test, while the other participant completed the test after a one-week-delay. In the CIT, half of the items were presented at the congruent abstractness level either categorical or exemplar , whereas the other half were replaced by the corresponding test stimulus at the incongruent abstractness level, leading to a crossed design that investigates the optimal item selection for memory detection while maintaining both sensitivity and specificity.
The study was approved by the ethical committee of the Department of Psychology of the University of Amsterdam CP A total of participants Their average age was Participants received course credits or a monetary equivalent as compensation. All participants provided consent before taking part in the study. Seven participants did not complete the full study and were therefore excluded from data analyses. Twenty-two participants were excluded due to low target accuracy on the CIT i.
This criterion ensured that only those participants who understood the instructions and took the task seriously were included in the data analysis.
Memory detection: Theory and application of the Concealed Information Test. Citation. Verschuere, B., Ben-Shakhar, G., & Meijer, E. (Eds.). (). Memory. Aug 20, Memory Detection: Theory and Application of the Concealed Information The Concealed Information Test has been supported by decades of.
The final sample for analysis consisted therefore of participants Seventy-one participants Participants were told that they were going to plan a mock robbery and would work together as partners in crime. The crime scenario consisted of a coherent story based on eight critical details, of which four presented in their categorical form and four in their exemplar form: Participants encoded that they had met each other in the sports club exemplar: volleyball club and planned to rob a bank exemplar: SNS bank in their residence of South-Holland exemplar: Delft in May exemplar: May 26th.
Because they might not be able to flee the scene without a fight, they would bring a knife exemplar: butterfly knife. The partners in crime plan to steal expensive jewelry exemplar: ring and hide it at home exemplar: attic. During the CIT all participants were explicitly instructed to conceal their knowledge of the planned robbery. Participants were required to deny knowledge for trials containing critical details from the plan i. All eight critical items were presented at the categorical or exemplar level: two stimuli were encoded at the category level and were also presented at the category level e.
In two other instances, the stimuli encoded at the category level were replaced by the corresponding test stimulus in its exemplar form e. Lastly, target items e. Targets were always presented and tested at the same abstractness level as the critical items in the RT-CIT.
This questionnaire measured how well participants were able to focus on the screen during the CIT, how involved they were in the study, how well their memory was for the items of the planned robbery and the learned target items, as well as how much they tried to avoid detection and appear innocent in the CIT. To examine potential differences in memory performance between the immediate and delayed CIT condition, memory for the critical items of the planned robbery were assessed with a free recall followed by a recognition test after the full procedure.
Participants first had to freely recall the eight details from the encoding phase, in which they had planned the robbery.
Slowik, S. He concluded that whatever emotions were likely to be associated with lying, it would not be possible to determine if any given person was guilty by recording peripheral psychophysiology while denying an accusation. The midpoint of the give you feedback to this effect every few minutes. What factors account for this curious persisting gap between scientific progress and practical implementation? Table 2 Mean scores on the follow-up questionnaire 5-point Likert scale. We believed that it was probe P and one average irrelevant P Autonomic and behavioral responding to concealed information:differentiating orienting and defensive responses.
In the subsequent recognition test, participants had to pick the correct details from a list of all eight critical items intermixed with irrelevant options i. For recall, the number of correctly recalled details were counted, leading to a total score between, this represents the possible range 0—8. For recognition, items were scored as either correct 1 or incorrect 0 and summed, leading to a total score between 0—8.
Participants were invited to come to the laboratory in pairs and work as partners in crime while planning a robbery. The experimenter explained that it was important to remember the details from the crime as well as possible and to visualize actually committing the robbery. In order to prevent possible detection, participants were asked to align their stories as much as possible and study the details extensively. The experimenter first read the plan for the robbery out loud, with its eight critical details presented in either categorical or exemplar level.
Participants had to encode all items by writing down the words, reading it out loud and probing each other for the information.
During this encoding phase, the experimenter stayed in the room to assure that participants would not accidentally fill in an exemplar-level detail when aligning their story e. During the encoding phase, the experimenter asked the pair additional questions to stimulate richer encoding of the crime items and to contextualize the critical details e. Then, the experimenter asked participants one by one to repeat the eight critical details from the robbery, until all items were recalled correctly.
Lastly, participants filled in the missing details of the story on paper, followed by a free recall of the items. Participants were explicitly instructed not to discuss details of the experiment with each other in the one-week period between the encoding phase and the second session. In the second phase of the experiment, participants were asked to sit behind the computer for the CIT programmed in Inquisit 4. The experimenter explained that the police had received an anonymous tip about an upcoming robbery and that the participant was taken to the police station to undergo a lie detection test.
The participant was instructed to try to convince the police of his innocence and beat the lie detector test by hiding all information about the crime. Upon successful concealment, the participant would receive an additional 0. Footnote 1. Then, participants were asked to encode eight target items to which they should respond affirmatively in the CIT, while denying all other information i.
The eight targets were initially presented on the screen for 2 min and participants were asked to recall all items.
Then, they saw the targets for an additional 1 min before recalling them again and continuing to the practice phases of the CIT. For each of the eight critical details encoded in the crime scenario, the CIT included the correct answer, a target item and four incorrect answers serving as irrelevant options ratio For instance, if May was the critical stimulus, the target was July and the irrelevant stimuli were June, August, September, and October categorical Item Type ; if May 26 was the critical stimulus, the target was May 30 and the irrelevant stimuli were May 8, May 12, May 17, and May 22 exemplar Item Type.
All eight critical items, eight target items, and 32 irrelevant items were displayed exactly 14 times, leading to a total of trials in the test. These trials were divided over two blocks, each containing trials, with a self-paced break in between. The question and the response keys remained on the screen during the entire test as a reminder. Participants were instructed to respond with YES only to the target items and NO to all other stimuli i. Each trial consisted of one answer e.
Response latency was measured from the onset of the stimulus on the screen until one of the response keys was pressed. In order to ensure proper understanding of the task and instructions, each participant had to pass through a stepwise practice procedure that allowed participants to become used to the speed and the requirements of the CIT. Each of the three practice phases of the memory detection test consisted of 24 trials displaying a random subset of critical, irrelevant, and target items.
In the first practice phase, participants could pace the speed of the trial sequence themselves, so that a new stimulus only appeared after a key press. Feedback was given upon an erroneous response i.