Explanation of MCT Test Report

**Please note, at the bottom of this article there is a downloadable PDF test report of a Sample MCT test. After reading this article, please download the report for additional in-context information**


Explanation of MCT Test Report

The following information explains test report results for EyeDetect which use the Multi-Issue Comparison (MCT) test protocol. Included is basic background information, as well as other details directly related to the question of nature and scope of MCT test questions.


Cognitive Load

Theories of deception detection hypothesize that lying is more cognitively demanding than telling the truth.[1] Deceptive individuals use cognitive resources to inhibit the truth, fabricate the lie, and maintain its consistency, coherence, and believability over time.


Deceptive individuals may also surveil their own behavior and internal state of arousal to self-monitor whether they are leaking incriminating information, especially during an interrogation or examination[2]. During interrogation, they may also use additional cognitive resources to observe the behavior of any interviewers for feedback on their own perceived believability.


Inhibiting truthful responses, attempting to maintain credibility over time, monitoring the interviewer and self-monitoring for signs of information leakage are cognitive processes that require mental effort, and then distinguish deceptive from truthful individuals.


Lying requires more mental effort than being truthful, and physiological correlates of mental load are measurable.


Psychologists have long known there is a strong correlation between cognitive load and certain eye behaviors. For example, pupils dilate commensurate with increases in cognitive workload.[3] Classic studies conducted in the 1960’s revealed that the pupils dilate slightly when a person mentally multiplies 7 x 3 but dilate much more when the person attempts to multiply 17 x 31.


In the same way, the pupils dilate slightly when people respond truthfully to questions; but when they respond deceptively, the pupils dilate more.  The pupils dilate more when the person is deceptive because it is mentally more difficult to lie than to tell the truth.


Guilty individuals experience an increase in cognitive load that is revealed by other ocular-motor measures as well.  Other important indicators of cognitive processes associated with deception

include reductions in blink rate, response time, fixations, reading time, and rereading time. The effects of deception on these measures are more pronounced when the person responds to complex statements.


Test Questions

All lie detection tests use various types of questions to gather data about the examinee being tested. The question sets can include:

  • Relevant questions (those related to the primary issue of interest)
  • Comparison questions (those related to a secondary issue)
  • Neutral or irrelevant questions (those unrelated to the issue).

EyeDetect and polygraph test protocols are similar in that regard. Relevant questions (e.g., Did you rob the bank?) evoke a measurable cognitive response in a guilty examinee. For an innocent examinee, that same relevant question should evoke a smaller cognitive response.

In the same way, polygraph examinations record changes in physiological reactions to relevant questions. Those changes in measured physiology load on one group of questions or the other, as a function of deception or truth telling, are shown with respect to the relevant target questions (Nelson, 2015). 

Conversely, the comparison question generally invokes a larger magnitude cognitive response in innocent examinees as compared to the relevant question. These reactions are used to create a within-subject comparison of reactions to the two types of test question. In essence, the examinee’s reactions to the two types of questions are compared to determine if a deceptive or truthful pattern of responses was observed.


In some test protocols, the comparison question is a crime of serious consequence, but one that the examinee is not likely to have committed. In other test protocols, the comparison question is an issue that all examinees are guilty of having committed. Each test protocol has been designed, researched and tested to evoke specific responses in guilty and innocent examinees.


The irrelevant or neutral questions evoke a minimal cognitive response in all examinees but given that neutral questions are unrelated to the issue of primary or secondary concern, that minimal reaction is expected.


MCT Test Protocol

The EyeDetect Multi-issue Comparison Test (MCT) protocol is used primarily when conducting screening tests involving various questions. In MCT tests, EyeDetect and polygraph have similar protocols. They both use relevant questions, comparison questions, and irrelevant questions.


In the MCT, there are up to four relevant questions. Each can ask about issues of concern, such as:

  • Have you used illegal drugs in the past 6 months?
  • Have you committed a criminal act of a serious nature?
  • Have you lied about work-related discipline?
  • Are you a terrorist?

One of the relevant questions serves as a comparison issue, such as the question about terrorism. It is a serious issue, with a low probability of occurrence.

All relevant questions challenge the examinee’s goal of passing the test.  The questions that most challenge that goal are those that will cause greater physiologic changes in the examinee.


Psychologically speaking, when a person is asked about a relevant issue such as bank robbery and a comparison issue such as involvement with terrorists, she/he tend to focus more attention on the issue in which she/he may be involved (i.e., bank robbery) to ensure she/he will not fail the test. Most people will be less concerned about the comparison question, since it’s highly likely they were not involved in terrorism.


The guilty person will invest more cognitive effort processing the relevant questions about bank robbery, as they pose the greatest threat to the goal of passing the test. An innocent person will be less concerned about all issues and should exhibit a lesser cognitive response for all questions.


Test Report

The EyeDetect test report includes a section “Test Response Summary” that indicates the examinee’s responses to up to four relevant questions, one of which serves as a comparison question. 


The following is an example of the test report section for a relevant question about drug use. The left column labeled “Statement” shows the questions asked of the examinee.  The second column labeled “Correct Answer” indicates what the expected response would be from examinees taking the test. In other words, whether the examinee is innocent or guilty, unless a guilty person confesses, all examinees deny the use of illegal drugs. Therefore, the “Correct Answer” indicates a denial of that issue.  The green circle (correct) or red circle (incorrect) indicate how the examinee responded to each question. If no response is given, it is called a “Time Out.”




In the example shown above, the examinee responded incorrectly to two of the questions. Important note: The number of incorrect or correct responses is less important than the intention of the examinee when responding. In other words, if a few answers are incorrect when responding, it will not affect the outcome of the test because when an examinee responds deceptively, the cognitive load invoked will be that which is observed in guilty examinees.


Along the same line, a guilty examinee may answer all test questions correctly while still obtaining a deceptive test score. This occurs because the savvy examinee knows what the correct question responses should be, but the cognitive load invoked will be that of a deceptive individual.


The following image shows a sample test report section for the relevant question of low probability (comparison question) such as involvement with terrorists. The left column labeled “Statement” shows the questions asked of the examinee.  The second column labeled “Correct Answer” indicates the requested response for all examinees taking the test.




In the example shown above, the examinee did not respond to one of the questions. In some instances, this could be due to a lack of concentration or simply because of a mistake.


Regardless, if the examinee intended to answer the questions as instructed, the cognitive load invoked will be similar to that of a person that answered correctly. 


[1] Johnson, Barnhardt, & Zhu, 2005; Kircher, 1981; Vrij, Fisher, Mann, & Leal, 2000.

[2] Kircher, 1981

[3] Kahneman & Beatty, 1966

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