Title: Psychology 323: Deception
1Psychology 323 Deception
- J. P. Rosenfeld, Ph.D.
- jp-rosenfeld_at_northwestern.edu
2We should spend an equal time on phenomenology
and MECHANISMS of deception.
- as we do on DETECTION of deception. But there is
a lot more research-based (real) knowledge about
the latter, so most of the time, thats what we
will cover.
3Regarding detection there are two approaches
-
- 1. Behavioral
- (a) non-verbal
- (b) Verbal
- 2. Physiological Nervous system activity.
- .We start with Behavioral
4Are the following notions True?
1. People typically reveal their lies by
fidgeting, acting nervous, avoiding eye contact,
etc. 2. Therefore, we are rather good lie
detectors (unless we are very stupid). 3. This is
especially true when we detect lies in those
close to us. 4. Criminals, con-men, professional
crooks, and such, however, are harder to spot
for us lay people. 5. Fortunately, trained
professionals (police, FBI) are superior lie
detectors, so they protect us against pros.
5We wish we had a Pinocchio's nose indicator
6But we dont
- NONE of those assertions is true!
7- People think they are great lie detectors. But
they miss many lies. Why?
8- (1a) If someone thinks you look great, why
argue? (Vrij Ostrich effect)
9- (1b) Ill ask no questions(and hope you tell no
lies!) - Bill to Hillary Ah did not have sex with that
woman..
10- (2) Lie detection is tough!
- There is no behavioral or physiological specific
index of deception, though things are not as bad
a Vrij suggests P300, fMRI
11Beware of internet Media claims!
- Pavlidis thermal imaging not so great
- BEOS Brain Electrical Oscillations Signature is
Bogus! - Brain Fingerprinting?! (See my critique.)
12How common is lying?
- A) once a year?
- B) once a month?
- C) once a week?
- D) More than daily?
13Definition of lying
14- Intentional, without warning, misinform or
mislead another. - Liar must believe information is false.
- Lie could fail.
15Taxonomy of Deceptions
16From Bad-est to least bad
- (1) Outright Lie (total B.S.)
- John Edwards I am not the father of that child,
no way, Ill happily take a DNA test. - Stating I didnt do it while knowing one did.
17(2)Exaggerations (overstatements) or
Minimizations(understatements)
- I am the most eminently famous researcher in the
Psych. Department. (but almost) - This is an important discovery of mine not yet
published (which was actually rejected by one
journal and now in review at another.)
18(3) Subtle Lies (Omit details)
- Clinton Ah did not have sex with that woman,
Miss Lewinski - (Not according to the usual definition
intercourse.)
19(4) Concealment
- How was your day?mine was as usual
- Heaven forbid she asks me about my day!
20Why do people Lie?
21Many reasons
- (1) Material Gain
- (2) Avoid loss/punishment
- (3) Avoid embarrassment
- (4) Make good impression ( get the job)
- All these involve gain for oneself.
22The other kind of (Other-directed) Lie
- Altruistic Lies
- You made a great impression
- Telling a gravely ill person (child) that she
will be fine..
23Why is it hard to know for sure how often people
lie?
- Self report fails because people dont want to
recall. - But 2 times a day is a reasonable occurence.
24Whom do people lie to?
- Strangers more than close contacts. (Why?)
25Attributes on which to classify Liars
26(1) Gender
- Men tell more self-oriented lies.
- Women tell more other oriented lies
27(2) Age
- What is definite minimum age for lies in
children? (2,4,6,8,10) - What motivates youngest childrens lies? (Gain of
say cookies? Avoid punishment? Make a good
impression?)
28(3) Personality Type
- In romantic relations
- (a) attachment style avoidant (lack of trust,
keep people at distance)..these folks lie to
keep others at a distance. - Versus
- anxious attachments lack of self-esteem. These
people lie to look good as they feel bad.
29(b) Psychopathy
- The types have no empathy or sympathy for others.
They regard others as pieces of themselves, and
objects of manipulationlike their own limbs.
These are big time liars to everyone they might
wish to manipulate. Superficially charming, they
get away with it for a while
30 (c) Extraverts and introverts
- Outward/sociable vs. reserved.
- Which are the bigger liars?
31(d) Self-consciousness
- These are very concerned with impression they
make, so how do they behave with respect to
deception? - In this connection, one speaks also of social
anxiety they lack self confidence, so they tell
tales.
32Are there non-verbal, behavioral lie signals?
- (Are we all on same page? What are these?)
33We wish we had a Pinocchio's nose indicator
34DiPaolos group emphasizes 3 theoretical
perspectives
- During deception, 3 phenomena occur
- 1) emotional reactions guilt, fear----and
delight. (delight?) - Guilt ? low eye contact
- Fear ? stuttering, blinks, squeals.
- Delight (of duper)? excitement, inappropriate
laughter. (Ekman)
35 What else does liar experience?
- 2) mental demand, also called cognitive load.
Liars will also tend to look away, so as to
concentrate on made up details. Except when they
monitor you to see if you believe. - 3) Attempted self control of behavior to avoid
tells. Not easy. Voices break, facial expressions
occur Ekmans micro-expressions.
36Remember
- These are theories of what should happen.
Moreover
37these effects are affected by certain factors,
e.g.,
- GUILTThe degree of guilt felt depends on
personality. Consider Psychopathy. Consider
Stakes Consider sense of righteousness or duty
felt by CIA agent. - FEAR Experienced liars of whatever breed have
less fear. - EXCITEMENT helped by audience. Also, if its a
big conquest, or else, no.
38More
- COGNITIVE LOAD--- also depends on verbal
skill-intelligence and experience. (Vrij is wrong
about Psychopaths feeling less load.) Degree of
rehearsal also makes a difference (practice makes
perfect!) - SELF CONTROL depends on Psychopathy.
39Vrij is a pain, but best we have..(E.g.Box 3.1 p.
47).
- and his best statement is on the top of p. 49.
the relationship between lying and non-verbal
behavior is complex. The implications of this
statement regarding development of non-verbal
tells is what?! (Life is not Poker.)
40Research Methods for studying behavioral
non-verbal signs of lying
41Field Studies.(Define.)
- We want to compare liars vs. truth-tellers, but
- Difficulties
- 1)Getting videos (Are cameras always running?)
- 2) Establishing Ground Truth.
- 3) Controls only possible in lab to have
unconfounded conditionsso not many field studies
re nonverbal cues are out there
42OK, how about lab studies?
- Pluses Ground truth easy to get by design.
Likewise, un-confounded control conditions. - Minuses Lies are instructed. So what happens to
guilt? fear? What happens regarding stakes? You
can offer lots of money, but not punishment (as
in real life). - DECEPTION HARD TO STUDY!
43Bottom Line
- Vrijs Appendix 3.1 makes very clear that there
is NO reliable non-verbal sign of deception.
There may be trends and even significant group
effects (explain), which support theoretical
views noted above.. - But in D of D, the key statistic is INDIVIDUAL
HIT RATE (as in d from SDT).
44Dramatically
- Is there such a thing as lyin eyes? Are gaze
or eye contact helpful? - Are liars more emotional than truth tellers? Why
or why not?
45Vrijs Group Differences (p.67).
- Very suspect!
- As is rest of chapter about Clinton, Saddam
Hussein, Huntley. - Amazing that he says look for the cluster of
c(l)ues to deception, not single c(l)ues. Which
cluster? There is no straightforward answer.
46Verbal signs ("cues" clues?) about deception
47We wish we had a Pinocchio's nose indicator
48(No Transcript)
49Vrij description of possible verbal signs
(cues)
- .as in his box 4.1 list is mostly pathetic,
i.e., wrong (imho). - On the other hand, sometimes one has to say,
duhhh! as when he states that direct statements
are more credible than evasive ones. - Obviously plausibility helps! As does consistency
(lack of contradiction).
50But Vrij best statement is
- As I will demonstrate, a verbal cue uniquely
related to deception, akin to Pinocchio's growing
nose, does not exist. (p. 103) - Again, an appendix(4.1) shows some trends group
effects as supporting some views in Box 4.1. - Again, clustersgt singles. But which cluster? No
one knows.
51Vrij indulges himself with many I think.. type
ideas.
- Thats fine. Be sure you do not confuse these
hypotheses for facts! - Note people researchers always start out with
what appears obvious, like twitches speech
signs. These all are ultimately controllable,
unlike physiology (looking ahead).
52Henceforth.
- We will be looking at more specialized and
developed approaches to detecting deception. Vrij
still likes more immediate (non-physiological)
tools, because they are allegedly quick, easy,
cheap. Imho, he stretches things by emphasizing
how laborious some methods are...
53OK,
- fMRI requires a 1M machine and an annual budget
of gt1M - But when Vrij states (p. 189) that EEG/ERP
recording usually requires 10 or more scalp
electrodes, he exaggerates 2 (actually 1) will
do, and it takes only 5 minutes to hook up. - But Vrij we will go on with SVA, RM SCAN,
imho, unphysiological extensions of what we just
did
54More complex behavioral methods
- Reality Monitoring, Statement Validity
Assessment, Scientific Content Analysis.
55Reality Monitoring
- RM started not as a DoD method, but rather as a
discipline in Cognitive Psychology to study on a
theoretical basis, the differences between
perceived versus imagined experience as with
false (but honestly believed) memories.
56What are the characteristics of Real versus False
Memories..
- with regard to
- Sensory Information?
- Contextual Information?
- Affective information?
- Think of dimensions of clarity versus vagueness?
- Give examples of what you might actually remember
about an event.
57This Q A system of M. Johnson sorta works, but
- What happens as time passes?
- So what do you remember better, last week or when
you were 3?
58Actually
- Actually, it turns out that Physiology (ERPs)
come to the rescue again regarding false
memories - as we will see later.
59If RM is not a perfect false memory detector,
then why..
- would we think this strategy would be a good
deception detector? - Are there differences between false memories and
deceptions? - HINT What do subjects believe about veracity of
f.m. and lies?
60RM Criteria (after Sporer 97) with some overlap
with CBCA
- From Vrij Table 9.1. The first 7 should be there
in true statements. - Clarityclear sharp, vivid statements
- Perceptual info.details of smell, sound, etc.
- Spatial info.details of location, seating
arrangement, object location. - Temporal Info When things happened, and in what
order. - (continued)
61Four more
- 5. Affect detailHow subject felt I was
disgusted when I saw the body - 6. Reconstructability of the testimony in
detail. - 7. Realism Is the story plausible, realistic,
logical? - 8. Cognitive operations. Should be less in true
story It shouldnt be necessary to make
inferences He appeared nervous.
62The RM method usually involves 2 raters scoring
tape.
- Inter-rater reliability should be and is found by
research to be high. Good as CBCA, anyway. - Vrij thinks its easier to learn and teach,
because - There are fewer criteria which are more concrete
and thus less subject to interpretation.
63Vrijs review of RM research in Appendix 9.1 has
limitations
- Not all reviewed studies are peer-reviewed
publications. - Not all studies are given!
- Scoring not standardized.
- Some listings lack inter-rater data.
- Only recent events are studied.
- RM is problematic in children.
- Etc, etc. maybe not important .
64...because
- Appendix 9.1 shows a mostly mixed pattern.
- Average accuracy is 68.8 overall, which mean
many false alarms (about 29 in truth tellers)
and misses (about 34 in liars). I.e., group but
not individual results.Yes, RM beats flipping a
coin, but not by much. More work is needed.
(Physiology wins.)
65 66Scientific Content Analysis
67Israeli tool
- Vrij Widely used, though
- Not much researched, nor endorsed by researchers.
68Basic assumption
- A memory based on actual experience will differ
in content and quality (?) from an invented or
fantasized memory. (Duhhhh!) - Also problematic Not all lies are invented out
of whole cloth. Some are substituted actual
memory, as in most alibis.
69Proceedure
- Suspect writes in handwriting a statement of
events in absence of investigator (to avoid
contamination). - Statement is then scored on several criteria
70The Criteria ( seen in truth tellers. V means
vs. CBCA)
- Direct denials
- Specific identifications
- Cross-outs(against instructs.) V
- Vague memories V
- 20-50-30 structure
- Emotions
- Subj/obj time correspondence
71More.
- 8. Events in chronological order
- 9. Missing info A bit later.. -
- 10. 1st person, present tense
- 11. Pronouns I Ownership.
- 12. Change in language(???) Change from
conversation to Discussion. - if not
justified. Too subjective (imho) -
72Research results with SCAN
- 1. Field study .77 TTs, .88 Liars at best with
Denial criterion. - .But, as with almost all field studies, no
ground truth!!!!! So, fuggedaboudid! - 2. Lab Study(So no ground truth issue) Three
crirteria utterly failed to discriminate liars
and truth tellers!! So, fuggedaboudid!
73Final field study
- Again no ground truth!!
- Though they claim75 TT accuracy, 80 liar
accuracy. - Great lack of consistency among SCAN users So,
fuggedaboudid! - Bottom SCAN line Little empirical support,
little standardization. - Thus the widespread use is stupid.
74Protocols for Physiologically based Deception
Detection
- Based for openers on Polygraph.
75Polygraph
- Does not mean lie detector.
- Means a machine with many (poly) channels of
visually presented (graphical) information in
inked paper or laptop display format. - A Polygraph machine can be and is used in many
fields of Psychophysiology
762 Major Protocols currently used
- Comparison (Control) Question Test (CQT)--
beloved by enforcers, cuz its easy to use
(Didja do it?) and tends to elicit
confessionsbut hated by academics who prefer the - Guilty Knowledge Test (GKT better known as the
Concealed Information Test (CIT), since knowledge
cant be guilty (just perps.) - Both utilize autonomic arousal.
77Why do us professors frown on CQT?
- Pre-test interview cannot be standardized.
- It compares arousal responses to relevants.
controls.There can never be true comparison
control questions in the scientific sense of
control.(Yet there could be better versions.) - High false positive rate (which CIA et al. dont
care about.)
78Why do we love CIT?
- It compares arousal (?) responses to critical
(probe) and non-critical (irrelevant) stimuli. - There are usually 6 or more multiple choice
questions with 1 5 choices per question. (Throw
away 1st.) Thus for each item, the P(chance hit)
1/5.2 - For 6 INDEPENDENT items, probability of subject
hitting on all 6 by chance P .26 .2 x .2 x
.2 x .2 x .2 x .2. Use Bernoulli for chance hits
on lt 6. Thus you can reduce the false positive P
as low as you like by adding independent items
(not always so easy). -