posted 06-26-2008 12:42 PM
Bob,Thanks for the interesting case.
While we're involved in all of this fun psychologizing of the CQs, lets not to forget to also torment the RQs some.
What we're really talking about is the decay of the signal value of any CQ material in the subject's. We've not studies this well, so all we can do is guess, hypothesize and state our expert opinion (keeping in mind that expert opinions in science are worth about the same as non-expert opinions).
We can't reasonably talk about decay of the signal, which is really the issue of desensitization or habituation, without also being willing to discuss the possibilities pertaining to sensitization and dishabituation. What we're really talking about is the saliency of the signals from the CQs and RQs.
This subject has had 20 years to ponder the RQ. What that could mean is that the RQ signal is perfectly clear, and salient. Meaning that a test subject might attend and respond physiologically to the RQs regardless of whether he did it. An opposite argument would be that he's had 20 years to habituate and desensitize himself to the RQ, meaning he might not respond to the RQ even if he did it – that would be a FN. On the other hand, conditioned response theory reminds us that there may be more than one way to condition a response potential, and that 20 years of consequences and rumination might accomplish that – with a corresponding increase in the potential for an FP.
Now consider what we know about orienting theory, including orienting and defensive responses, which are theorized to be differential responses to neutral/novel and threatening stimuli. The divergent validity of the OR and DR is week, so we're wise to be a little careful with this, but ORs and DRs are thought to play a role in the magnitude of differential reactivity to CQs and RQs. I don't think it would be accurate to take and “either or” approach to this without data and proof, so it is better to assume that both CQs and RQs may produce DRs. Neutral questions can be more easily assumed to prompt ORs. Run a few tests and you'll sometimes notice ORs to N questions that are as large as what we presume to be DRs to RQs. In my experience this is mostly in the EDA, not the cardio. If it is possible that a truthful subject, having pondered the RQ for 20+ years in prison and now hoping for parole, could perceive the RQs as more threatening than the CQs then orienting theory cannot preclude the possibility of a FP. At the same time, at the same time, a guilty subject who has already served 20+ years may not experience any threat from the RQs, because he's already been consequenced, and may be calloused and cynical about the attitudes, intentions, and desires of persons around him. So, here comes the polygraph guy, who asked him “did you do it,” to which he experiences no real threat (he's already in prison). The polygraph guy then tries to take him for a ride over those other stupid questions that have nothing to do with whether he gets paroled. But the novelty of those issues may be unavoidable, so he reacts to them. What you now have is the possibility of a FN.
For the subject, all of this activity is occurring in the brain. It is doubtful that a polygraph guy is going to present at serious FFF level threat to a 20 year prison inmate - unless the polygraph guy is a meat-headed type who resorts to directly threatening the parole possibility. The problem with that approach is that the subject is then prompted to react to the examiner, not the question stimulus. Good testing science and good testing practices require that the test administrator is not the test stimulus, else the possibilities of errors and manipulated results are endless. Examinee excuses are endless too (“the polygraph guy was a jerk and he scared me, and I was reacting to him not the question”). So, most of the the cognitive activity will be in the prefrontal cortex, which is responsible for attention, problems solving, and judgment, with some activity in the Amygdala (which will evaluate the level of threat presented by the stimulus), and Hypothalamus (which plays a role in emotions, temperature, and the regulation of autonomic respiration). While the hippocampus is responsible for short term and working memory and the storage of information into long term memory, it is the prefrontal cortex, again, that is responsible for the processing of long term memories (i.e., RQ and CQ material). The prefrontal cortex, like the other lobes, is enervated by sympathetic acetylcholine. The postganglionic sympathetic neurons in the skin, which enervate the eccrine sweat glands, are also enervated by sympathetic acetylcholine – which is why orienting responses, distraction, and sometimes even mental activity will appear in the EDA (which may have more to do with acetylcholine than sweat per se – else why does the EDA work so well with bricklayers when an electrolytic gel such as potassium chloride is applied to the electrodes). Anyway, all of the business of attending to an RQ is simple – he did it or he didn't, but he has long ago decided what he's going to say and what ideas he will entertain in his head (prefrontal cortex) regarding the RQ matter. Activity is minimal. If he is guilty, we also have these blasted CQs to answer, and those are not so practiced or rehearsed, and may require more cognitive activity (in the prefront cortex) to decide upon and assure oneself of the best answer. What you now have is the formula for a FN result. On the other hand, if the RQ prompts a return to rumination or perseveration – because the RQ issue is the one that may help decide a parole opportunity – and those CQs are regarded as mere inconveniences, then a truthful subject could exhibit greater reaction to the RQs, with a corresponding FP result.
You'll notice that each of these three well establish psychophysiological constructs may play an important role. All of them begin to explain why the CQT works. None of them are adequate by themselves, and none of them can preclude a FN or FP error. It is generally regarded as unwise to limit ourselves to a single mechanism or theoretical framework. Instead what we should do is develop an integrative understanding of various well established constructs that explain the CQT.
I disagree with the suggestion that we don't have a proven construct to explain the CQT. We have several, its not our job to prove them, but disprove them. I think we have dis-proven the ideas of “fear” and FFF. FFF itself is a global and diffuse reaction. Polygraph reactions are more discrete. Fear theories cannot account for DLCs, cannot account for the effectiveness of the polygraph with psychopaths, and cannot account for the convergence of results between laboratory and field studies. Conditioned response theory, orienting theory, and neuro-cognitive theories can account for DLC's, psychopaths, and lab studies. They can also help us to understand the possibilities for FN and FP results.
What we polygraph examiners tend to do is to degrade our own conversations and hypotheses into metaphorical inaccuracies , usually involving oversimplified and inadequate emotional explanations such as fear, guilty and FFF. We like metaphors like “hot,” and “wide,” because they are understandable and accessible. Most people will borrow conceptual language from simple or known phenomena when attempting to describe or understand complex or unfamiliar phenomena. It is important to remember that words like “hot” and “wide” are metaphors, and not take the concepts literally. Even words like “anxiety,” “stress,” “nervousness,” and “fear” (and FFF) are metaphors, because the polygraph does not actually measure those things in a literal sense. We do this primarily because we are not adequately conversant with the psychological theories, or are afraid of the big words. Its time not to be afraid of the big words.
Cognitive Dissonance is another example. Cognitive dissonance is a concept that comes from cognitive psychology, just as Anxiety is a concept that comes from psychodynamic psychology. Cognitive dissonance does not come from anxiety, it is said to come from attempting to hold two incompatible ideas, or ideas that are incompatible with behavior. For example: a person enjoying a cigarette during a break, would experience cognitive dissonance if he told himself “smoking is disgusting, unhealthy, and will eventually kill me,” instead of “how nice, a break, and relaxation from a smoke.” Cognitive dissonance is thought to motivate behavior and to eventually increasing the likelihood the person stops smoking. The second statement (relaxation) is non-dissonant, and consonant with continued smoking. Cognitive dissonance is an alternative theory to psychodynamic anxiety. Cognitive dissonance is the idea that a new idea or information that is incompatible with previously held ideas will begin to create a change in something (hopefully behavior, but sometimes in ideas). Sometimes, incompatible or dissonant cognitions are reconciled with a third idea. At other times dissonant ideas or dissonant information is reconciled by simply rejecting or ignoring the more intolerable idea (For example, see the UFO expectancies, or observe the arguments for sticking with complex polygraph scoring systems in the face of scientific evidence that says complex models overfit data more readily, generalize to new data less efficiently, and have poorer interrater reliability).
It's OK to borrow language and concepts while learning, but be careful not to take the words literally.
I think ebvan is on point regarding the richness (another metaphor) of CQ material while incarcerated. You could work this a number of ways, including descending (another metaphor) into criminality even though he didn't do it, giving up on decency, bad behavior rubbing off on him (another metaphor), maintaining his integrity even though wrongly convicted, general imperfect humanness and the need to “get everything out of the way of the test result, but still look good for the Parole Board.”
My suggestion is to refrain from overly psychologizing this case or any other case. I've said it before, and I'll say it again – we polygraph examiners do a lot more psychologizing than any psychotherapist or psychologist whom I know. We allow ourselves to believe that we know what is going on in the mind of the subject. We don't and we can't.
Consider the possibility of an undetected prior murder (its good to consider it). Do we believe that an undetected murder, for which he can simply say nothing and never be prosecuted, would cause the CQs to become more salient for a guilty convicted murderer, who may or may not get parole depending on his reaction to the specific question about the known murder? It's OK to wonder about this, but it seems unwise to try to settle the question with our opinion.
Opinions are great, and discussions are great. Just remember what they say about opinions: like certain parts of the anatomy, everybody has got one, and anyone without an opinion is full of S%$^*. Obviously, I don't subscribe to the version of this adage that suggests no-body wants our opinions. To me that is too much like “don't think for yourself,” which in psychotherapy and family therapy is like telling people not to be smart, and not to “be” (in the shakespearian or existential sense). Its called “bad parenting.” People are supposed to think, and have opinions. We are also supposed to be responsible with our opinions, which means not imposing them on others while sharing them. Data and knowledge from research is different than opinion, and it is reasonable to ask people to respond to knowledge and data.
Remembers that what we do in polygraph testing is to make inferences about the probability of a subject's truthfulness or deception, based on measured differential reactivity to the saliency of test stimuli which involve the target of the investigation and comparison material in the form of probable or directed lies.
Despite all of the complexities above, our collective practical experience tells us that the polygraph works, and. Our experience also tells us the polygraph is not perfect.
Keep in mind that this subject now has 20 years of prison inmate head-games, and may be a bit difficult to manipulate, intimidate, or fool. He'll go along with what he chooses to, and he'll cooperate superficially when he perceives that he had to do so. But it may be tough to actually convince him of anything.
My suggestion is to run a good solid single-issue Zone with three similar versions of “did you do it.”
It would make most sense to use a Utah Zone, because the publications indicate it provides the best diagnostic profile for evidentiary purposes. I like the Army Zone, and the Bi-Zone/You-Phase, but it seems to me to make no sense to consider using anything but a Utah Zone in a case like this. (Lou?)
The Utah decision policies emphasize a grand total cutscores only, with no emphasis on spot scores. This has been validated and provides the best balanced in terms of sensitivity to deception and specificity to truthfulness. We know that the spot scoring rule increases sensitivity to deception, but at a cost of FP errors. There is a time and place for maximizing sensitivity, and other times and places for maximizing balanced accuracy profiles. This is an evidentiary test, and the Utah is validated this way.
Of course, you could always select one of those “perfect” or near-perfect techniques, from some cloistered laboratory that doesn't make its data or experimental models available for external review., and doesn't bother with things like being accountable for statistical integrity. I would go with the technique that came from a series of studies from researchers who employ sound theory and sound science, aren't afraid of showing and discussing math and statistical results, fully document their development experiments.
Utah uses time-barred CQs, but it's probably not wrong or invalid to conduct it without the time bars. Perhaps Gordon Barland knows more. (Gee it would be great to have someone like Charles Honts to chime in on something like this.) Because the issue is aged, and behavioral history both before and after the conviction may be complex, I like Barry's suggestion from the Canadians - “Not connected with this case,” in place of the time bar.
Score the test using a validated method – preferably one with good statistical and measurement theory, and one which can provide a statistical classifier.
Use a computer algorithm or two for discussion purposes, but select an algorithm for which you can understand the features and troubleshoot any discrepancies with your results. It also makes sense to select scoring algorithm for which there is a fully documented transformation and decision model, so that you are capable of understanding how the computer achieved the result. Especially, don't let the computer score data that you wouldn't score yourself (if it the data stink, exclude it from the analysis). Run enough charts to collect a sufficient volume of scorable/interpretable data (the Utah Zone allows up to five charts if necessary).
Then, show the charts to others and get feedback about any strengths and weaknesses – that way there is no surprise when the opposing counsel's expert wants to criticize a test, and you'll have your arguments prepared in advance.
But mostly, run a good straightforward test and don't overly-psychologize the event. Evaluate your subject before the test (get the records), and learn how to work him. Make the CQs into a set of probable lies that would be a bigger dilemma for him than the RQs, if he were truthful. Remember that the RQs will probably take care of themselves.
Just run a good test, with a good technique supported by good science.
We have not adequately studied long-term signal decay, sensitization, habituation, and dis-habituation. What we know is that these are real issues to wonder about, but its too soon to reach any conclusions. We also know it is just as unwise to settle unanswered research questions with our “expert opinion” as with some non-expert opinion. The little bit of data on retest habituation (only partially related to long term desensitization) issues seems to suggest that while the phenomena are real and observable, it may or may present an interfering variable to good polygraph work.
As always, all of this is just my,
.02
r
P.S. Thanks Polybob. These are great discussions. Even if we disagree, any discussion can amount to important new learning, as long as we have the discussion.
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"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)
Polygraph Place Bulletin Board
posted 06-25-2008 12:39 PM
