Terms Relating to Lie Detectors Explained – Letter C
- Card Stimulation Test
- See card test or stimulation test.
- Card Test
- One of several types of stimulation tests used in conjunction with the standard PDD examination. In the traditional card test the examinee is invited to select a card from a deck of cards and then is tested on which number, letter, color, or character is on the card. See stimulation test.
- Cardioactivity Monitor (Cam)
- One of several cardiovascular sensors used in PDD. The CAM sensor is placed on the end of the finger or thumb, and it detects changes in distal blood volume via small strain gauge sensors attached to a metal diaphragm. CAMs require electronically enhanced cardiograph components. While some consider the CAM useful, it is employed less often than the traditional blood pressure cuff.
- Cardiograph
- General term for any recording of heart activity. In PDD the use of a blood pressure cuff to monitor relative arterial blood pressure changes and pulse wave is more precisely described as sphygmography (recording of the arterial pulse) or occlusion plethysmography (partial blockage of circulation to measure volume changes in a body part). While cardiograph is not incorrect in this context, it lacks precision in denoting the actual phenomenon being recorded in PDD. The term cardiograph in the psychophysiological and medical literature most often refers to the electrocardiograph.
- Cardiograph Notch Control
- One of the selective enhancement features for the analog polygraph introduced by Lafayette Instrument Company in 1979. Designed to regulate the distinctness of the dicrotic notch in the electronic cardiograph tracing through filtering of specific frequencies.
- Cardiograph Response Control
- One of the selective enhancement features for the analog polygraph introduced by Lafayette Instrument Company in 1979. Used a variable high- pass filter that permitted the operator to regulate the amplitude of the slow wave component (relative blood volume) of the electronic cardiograph.
- Cardio-Pneumo-Psychograph
- A two-channel polygraph developed by John Larson in the 1920s and used in criminal cases to uncover deception.
- Cardiosphygmograph
- Alternate term for the pulse wave and relative blood pressure tracing used in PDD. While the term cardiosphygmograph was common parlance in the 1930s through 1950s, it is used less frequently today even though it is more precise than the current expression cardiograph or its abbreviated form, cardio.
- Cardiotachometer
- Instrument that measures heart rate. Since heart rate can only be accurately measured over several seconds, real-time displays usually reflect the inter-beat interval that has been converted into the reciprocal to give the cardiac rate.
- Catacrotic Limb
- Descending portion of an arterial pulse wave.
- Central Nervous System (Cns)
- That portion of the nervous system consisting of the brain and spinal cord. CNS activity, although closely integrated with autonomic nervous system (ANS) activity, is not separately considered in traditional PDD approaches. It has been used with event-related potentials (ERPs) in Concealed Information Tests.
- Chart
- Graphical record of phenomena. In PDD it refers to the polygram on which is recorded the physiological activity during testing. The term chart is sometimes used interchangeably with test.
- Chart Identification
- Information annotated on a PDD chart by the examiner to record identifying data such as date, time, test number, examiner, case number, signatures, fingerprints, or other details required by the polygraph program. Not to be confused with chart markings.
- Chart Markings
- Annotation of the physiologic tracings to denote stimulus (question) onset and offset, examinee’s answer, question number, question label, artifacts, and other details important to the interpretation of the physiological data.
- Chemical Countermeasures
- See pharmacological countermeasures.
- Cheyne-Stokes Respiration
- Periods of cyclical variation in the amplitude of respiratory cycles interspersed with periods of apnea. This pattern of respiration is usually associated with brain damage, congestive heart failure, kidney disease or drug abuse.
- Chi-Square Test (C2)
- A nonparametric inferential statistical test based on the chi-square distribution. The chi-square test is frequently applied to determining the randomness of deviations between observed and expected values. Generally, the test is used to evaluate hypotheses dealing with the relationship between two categorical variables and “goodness of fit tests.” The chi-square test lacks the sensitivity of other available methods and is used primarily when the data can only be tabular in form. It is often reported in PDD literature, principally when comparing groups of test outcomes.
- Cholinergic
- Those neurons that release the neurotransmitter acetylcholine.
- Classical Conditioning
- Characterized by the establishing of a response to a stimulus that does not normally evoke the response. The Russian physiologist Ivan Pavlov reported producing a conditioned reflex in dogs during the last part of the 19th century. He used the sight of food (unconditioned stimulus) to induce salivation in the dog (unconditioned response) and fostered a mental connection between the food and the sound of the bell, and the bell’s ring became the conditioned stimulus. It is theoretically possible to classically condition physiological responses to occur uniquely when a subject is deceptive, and this method is one of the promising areas of future research in lie detection. Petty & Cacioppo (1981).
- Clearing Chart
- Usually, a Relevant/Irrelevant screening test used after a breakdown test, and includes the remaining relevant test questions that were not covered in the breakdown test. In the field it normally involves one chart.
- Clinical Approach
- Assessment technique used in PDD that includes the use of extra-polygraphic information to arrive at a conclusion of truthfulness or deception. Also called global analysis.
- Closed-Eyes Technique
- As the name indicates, it is the PDD examination in which the examinee is instructed to keep his eyes closed during testing. This method is used by a minority of PDD examiners, and questions about the effects of open or closed eyes have not been thoroughly investigated.
- Community Safety Examinations
- A broad category of examinations that serve to detect and deter illegal behaviors that jeopardize the safety of communities. Types of community safety examinations include Post-Conviction Sex Offender Testing (PCSOT), Intoxicated Drivers on Probation (IDOP), and Domestic Violence Offender Testing (DVOT).
- Comparative Response Question
- Name given by John Reid in 1947 for what would later be called the control question, and ultimately comparison question. See comparison question.
- Comparison Question
- Type of question used to elicit responses that are compared with the responses to relevant questions. There are two main types: directed lie (DLC) and probable lie (PLC). Subtypes for the DLC are the trivial and the personal. For the PLC they are the exclusive (exclusionary), and non-exclusive (inclusive). Historically called control question, comparative response question, and emotional standard.
- Comparison Question Technique (Cqt)
- An umbrella term for standard testing formats that use probable-lie or directed-lie comparison questions. Included are the Reid, the MGQT, the Zone Comparison, the Positive Control, the Utah, the Arthur, the Quadri-Track, and the Test for Espionage and Sabotage. None of the following are considered CQTs: Relevant/Irrelevant, Peak of Tension, and Concealed Information Tests.
- Comparison/Control Question Validation Test
- Test procedure in which probable-lie comparison questions are tested against relevant questions from a contrived crime to theoretically verify that the subject will respond to the comparison questions. These questions are then carried into the actual testing. Proposed and taught by James Matte and used in his testing technique, though not a widespread practice nor are there any published data in support of the theory. See: Matte (1976).
- Computer Assisted Polygraph System Caps
- System developed by David Raskin and John Kircher of the University of Utah that permitted modified field analog polygraphs to interface with a computer. Signals were extracted from the pen drive motors and routed to an analog-to-digital converter, where they were digitized, stored, edited, and analyzed. Discriminant analysis was used to weigh and combine measurements, and the software produced a statement of the probability of deception. CAPS, which stood for Computer Assisted Polygraph System, was later replaced by CPS, Computerized Polygraph System, which used a computer without the analog polygraph. Currently manufactured by Stoelting Instruments.
- Computer Voice Stress Analyzer (Cvsa)
- National Institute for Truth Verification produces the CVSA, first introduced in 1988. The company advertises that this device was developed from the Psychological Stress Evaluator (PSE) and is widely distributed amongst law enforcement agencies. Examiner certification is required. The CVSA testing format is dissimilar to PDD formats. Like other voice-based deception detection systems, published scientific research has failed to find any accuracy with the CVSA. See Psychological Stress Evaluator (PSE) and voice stress analysis.
- Concealed Information Test (Cit)
- Otherwise known as the Guilty Knowledge Test. The CIT is actually a series of tests, perhaps as many as 10, in which there is only one critical item in each series, much like the better-known Peak of Tension tests. The tests are constructed so that the order of the item presentations is randomly selected, except the first item which is used as a buffer. The theoretical operating mechanism of the CIT is there is greater signal value in the critical item for guilty examinees than in the irrelevant items. The CIT is believed to rely on cognitive processes, and is therefore not subject to false positives from nervous examinees. CIT tests could be used in a small proportion of all criminal cases where sufficient details were available to construct it, however in most crimes such details are lacking or would be already known to innocent persons via the media or investigating officers. Despite assertions of theoretical superiority of the CIT over the CQT, the CIT has practical limitations that have hindered its broad acceptance among field practitioners. Moreover, the preponderance of independent research suggests that false negatives may be a problem with the CIT. See Lykken (1959); MacLaren (2001); Podlesny (1993).
- Conditional Probabilities
- A statistical concept in which the likelihood of an event is predicated on a set of conditions. Conditional probabilities are expressed as p(AB), which may be read as: what is the probability that event A will occur given event B has occurred? More specifically, a false negative polygraph result can be represented as p(no evidence of DI responsesthe person is lying). Conditional probabilities are important when characterizing the accuracy of PDD. The following illustration is one offered by critics of the use of PDD in screening. Suppose that PDD is 90% accurate in detecting both deception and truthfulness. Also, assume that it is used to test 1,000 government employees, only one of whom is involved in the activity of interest, say, treason. There is a 90% chance that the one guilty person will be caught. Of the 999 innocent employees, 899 (90%) will pass the examination, and the remaining 100 will be false positives. The ratio of true positives (1 guilty) versus false positives (100 innocent) is a low payoff if the consequences are employment termination or criminal prosecution. Not used in this example is the influence of repeated testing and other methods that can reduce false positives, but it is clear from this example that PDD validity estimates are not well represented by a single percentage. See base rates.
- Conditioned Response Theory
- One of several theories that attempt to explain the underlying mechanisms of PDD. Conditioned response theory holds that physiologic responding is the consequence of an emotional response triggered by the conditioned stimulus. When a given stimulus is associated with strong emotions, larger responses are expected. There is some support for this theory in that physiologic responding has been established to be positively correlated with the personal significance of the test question. It does not explain why PDD continues to work in non-threatening and low motivation conditions, however. The conditioned response theory is not the prevailing explanation for PDD.
- Conductance
- Capacity of a material to permit the flow of electricity. Skin conductance is a common measure used in PDD. A related measure, resistance, is the reciprocal of conductance.
- Confabulation
- The reporting of information from imaginary experiences to fill in gaps of memory without any overt intention to deceive, though the information is most likely false. Confabulation can be a symptom of some organic brain disorders, though developmental factors explain other cases. The effect on deception tests has not been investigated.
- Confession Criterion
- A potential confound in field research on polygraphy. If cases are selected for research that use confession as a form of confirmation, then the study sample may be biased, for the following reason. Standard practice in polygraphy is to only interrogate after a deceptive outcome on the examination. Therefore, confessions will only be obtained from examinees who failed the examination, but not from those who managed to defeat the examination. The sample will then represent those cases in which the examinee was caught by the original examiner, rather than all cases in which the examinee was deceptive. It has been asserted that the use of the confession-verified cases in blind scoring studies to assess polygraph validity may overestimate the accuracy of the polygraph, because they may have charts in which deception is the easiest to interpret. Most field studies that have examined this source of research error have not a meaningful effect, though the issue is still hotly debated. See: Horvath (1977); Honts (1996); Iacono (1991); Krapohl, Shull & Ryan (2002); Patrick & Iacono (1991); Raskin, Kircher, Honts, & Horowitz (1988).
- Confirmatory Testing
- PDD examination used to verify the statements of suspects, witnesses, and victims.
- Conflict Theory
- One of several theories that attempt to explain the underlying mechanisms of PDD. According to conflict theory, the simultaneous activation of two conflicting tendencies, such as the motivations to lie and tell the truth, results in physiologic arousal. The greater the conflict, the larger will be the response. This explanation arises from the work of Luria in the 1920s and 1930s. The conflict theory predicts that psychopaths, by virtue of a defective conscience, do not produce arousal responses as large as non-psychopaths, and this effect has been demonstrated in laboratory studies for psychopaths as a group. However, it does not explain well why phasic responses occur even when an examinee is not required to answer the question, or even when the examinee answers truthfully. The conflict theory is rarely cited as the principal explanation for PDD. See: Gardner, (1937).
- Conspecnificance
- Mnemonic device used in the instruction of PDD. It stands for consistency, specificity, and significance, three characteristics of a physiologic response indicative of deception. In order for response patterns to support a PDD outcome of deception, they must appear regularly to the same questions, manifest themselves uniquely to those questions, and be of a magnitude to be distinguishable from baseline variability.
- Constant Current Method
- Measurement of skin resistance where the current applied to the skin is held constant.
- Constant Voltage Method
- Measurement of skin conductance where the voltage applied to the skin is held constant.
- Containment Approach
- Criminal justice system, treatment team, and polygraph examiner working together in a team concept sharing information equally with the other members of the team. As an offspring some containment teams now include one or more of the following: law enforcement, child protective services, rape crisis centers, prosecuting attorneys, judges, and in some cases school counselors, victim advocates, and medical staff. See: Cooley-Towel, Pasini- Hill, & Patrick (2000); English, Pullen, & Jones (1996); Heil, Ahlmeyer, McCullar, & McKee (2000).
- Control Group
- The group in research that differs from the experimental group only in that the latter receives the positive manipulation pertaining to the independent variable. A control group is necessary to infer that the changes observed in the experimental group are the result of the independent variable. For example, if a researcher wished to know the effects of the drug diazapam (independent variable) on electrodermal responses (dependent variable), the group that did not receive the medication would be called the control group and the medicated group would be the experimental group.
- Control Question
- Superseded term, now call the comparison question. Class of questions used in deception examinations that serves to elicit larger physiologic responses from innocent examinees when compared to the relevant questions. There are several types, such as the exclusionary, non-exclusionary, probable- lie, directed-lie, the positive, and minor variations. The term “control” in PDD traces its roots to the 1930s and to what are now called stimulation tests. These tests were used as “controls” for the production of deception response patterns that would later be compared with responses to relevant questions in the Relevant/Irrelevant technique. In 1947 John Reid published a paper in which he referred to two types of questions as controls—one he called a “guilt complex” and the other a “comparative response” question, the latter being a probable-lie question. The “comparative response” question was called a “control question” in a paper published by Fred Inbau in 1948, and the name became the standard terminology in PDD for nearly 50 years. This was not the first use of this class of question, however. Walter Summers used similar questions with his Pathometer technique which he labeled emotional standards as early as 1939, and they were used by New York State Troopers from 1939 until at least 1952. Elizabeth Marston, widow of William Marston, and Olive Richard, Marston’s former secretary, reported that they had participated in deception examinations with Marston some years before in which “hot” questions were used for comparison. A typical hot question would be, “Did you ever think of stealing money from that safe?” Elizabeth stated during an interview that they did not believe it wise to publish these types of questions, and consequently they have not been generally credited with this contribution to the science. Beginning in the 1970s, critics of PDD noted that the word “control” as used in PDD tests did not meet the criteria of the term as used in science. The term has since been replaced by comparison question in publications of the American Polygraph Association, American Society for Testing and Materials, federal polygraph programs, and scientific papers. See: Waller, 2001.
- Control Test
- An alternate term for a known numbers test. See stimulation test.
- Correlation
- Measure of how one variable changes with another, for example, chart scoring ability and years of experience are positively correlated. Measures of correlation range from -1.00 (indicating a perfect negative correlation—as variable x increases, variable y decreases) to +1.00 (indicating a perfect positive relationship—as variable x increases, variable y increases). A correlation equal to 0.00 means that two variables are not linearly related. One should not infer cause from correlation; two variables can be correlated without one causing the other. For example, in most cities the number of churches and the number of criminals are positively correlated, but one does not cause the other. Both are correlated to a third factor, population.
- Cortisol
- A glucocorticoid or steroid hormone substance made from cholesterol found in the bloodstream which is produced by the adrenal cortex in response to stress. Cortisol replenishes energy stores depleted during an adrenaline rush by converting a variety of food sources into storage forms such as glycogen or fat.
- Counterbalance (Or Counterweight)
- Feature on analog polygraph recording pens used to adjust the amount of pressure the tips exert against the graph paper.
- Counter-Countermeasures
- Methods used to detect and neutralize those efforts an examinee has engaged in while trying to defeat the PDD examination. For example, if a PDD examiner concluded from an examinee’s behavior that the examinee had tried to dissociate during testing, he could insist that the examinee respond to the test questions with both a key word and the answer, thus ensuring attention to the content of each question. Lynn Marcy is credited with distinguishing counter-countermeasures (reactive) from anti-countermeasures (proactive).
- Counterintelligence-Scope Polygraph (Csp)
- PDD screening examination administered by the Federal Government on individuals with sensitive security clearances to detect and deter espionage, security breaches, sabotage, or other acts against the Government. Sometimes referred to as a loyalty examination.
- Countermeasures
- Generally, methods used to mislead an observer. In polygraph research it has been labeled as actions taken by the examinee to influence the physiological responses to produce a truthful test outcome. There are several typologies for countermeasures, depending on the definition used. Under some circumstances polygraph countermeasures have been found to be effective, such as when an examinee receives special training and feedback. Most spontaneous attempts are crude and ineffective. Various methods have been devised by PDD practitioners to deter and detect countermeasures. See Honts (1987); Krapohl (1996).
- Cover Question
- Keeler coined this term for a type of question that approximates what later would be called a control question. However, cover questions were also used to reveal other crimes of interest to the investigator.
- Cps
- Computer polygraph developed by Drs. David Raskin and John Kircher of the University of Utah. The CPS, which stands for Computer Polygraph System, is marketed by the Stoelting Instrument Company. Like its predecessor, the CAPS, the CPS has a discriminant analysis algorithm that weighs and combines physiological measures to calculate the probability of deception.
- Craniosacral Division Of Autonomic Nervous System
- An anatomical division of the autonomic nervous system (ANS) that represents the sites for outflow from the parasympathetic division of the ANS, i.e., some of the cranial and sacral nerves carry parasympathetic nerves.
- Credibility Assessment
- An umbrella expression for the multiple-disciplinary field that relies on physiological and behavioral measures to test the agreement between an individual’s memories and statements. Credibility assessment approaches have included reaction time tests, word association tests, polygraph, central nervous system measures, and behavioral analysis. See: Krapohl & Trimarco (2005).
- Critical Item
- In the Peak of Tension or Concealed Information Test, the critical item is the stimulus the guilty persons recognize from among the other items as being related to the event of interest. Sometimes called a “key”.
- Current Exclusive Comparison Question
- An exclusionary probable-lie comparison question in which the scope includes the time period of the relevant issue, but is excluded from the relevant issue by category, place, or some other delimiter. See: Matte (1996).
- Curvilinear Tracing
- Lines produced by analog field polygraphs that can become temporally distorted as the recording pens move up or down across the graph paper. This is because the vertical dimension of the graph paper moves in a straight line as time passes, but the recording pens pivot on an axis. Therefore, tracings will be rounded as they are recorded. Manufacturers’ offers of curvilinear timelines on the graph paper to help compensate for this effect were not accepted by the profession. Modern computer polygraphs have corrected this problem by rendering rectilinear tracings.
