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Cardiographic Detection of Deception

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Title: Cardiographic Detection of Deception


1
Cardiographic Detection of Deception
  • Jessica, Hieu, Pat

2
Detection of DeceptionHistorical Background
3
  • Through out the history of using
    psychophysiological measure to determine a lie
    there has been much controversy.
  • Lie detection is thought to have originated in
    ancient Hindu culture
  • There are also records of ancient Chinese culture
    using lie detection techniques that have
    psychophysiological basis.

4
  • Musterburg (1908) suggested that measures of
    emotional reactions, changes in heart rate, blood
    volume, skin conductance, and respiration should
    be investigated as an aid to determine the guilty
    from the innocent.

5
The Polygraph
  • Martson, an understudy of Musterburg, and his
    work with lie detection attracted the interest of
    two police officers, Larson and Keeler.
  • The polygraph was pioneered by Larson and later
    perfected by Keeler.
  • This type of polygraph is now known as the
    Keeler Polygraph and is widely used.
  • A polygraph is actually any instrument that
    measures more than one physiological response
    simultaneously.

http//static.howstuffworks.com/gif/lie-detector-p
arts.jpg
6
The Keeler Device
  • Measures electrodermal activity, blood pressure,
    respiration
  • Recently, event related potential (ERP) has been
    explored, specifically the P300 component.
  • It is apparent that the main measures of the
    polygraph are autonomic nervous system responses.

7
GKT vs. LD
  • Lykken (1959, 1974) distinguished between two
    different questioning techniques
  • Lie detection (LD) involves asking relevant and
    irrelevant questions and monitoring the
    psychophysiological responses
  • The guilty knowledge test (GKT) involves
    multiple-response situations and monitoring the
    psychophysiological responses.

8
Information Tests
  • Both the GKT and the CQT (control question test)
    are information tests.
  • Information tests presume that a persons
    critical information can produce differential
    physiological response to various items.

9
GKT vs. CQT
  • The GKT is superior to the CQT because
  • it can be standardized
  • error rates can be specified for the GKT
  • the GKT is also less prone to faking

10
Polygraph as an Art
  • Professional polygraphist rarely vary their
    techniques in a systematic way, this makes it
    difficult to establish the validity of the
    various aspects of procedures (Orne).
  • Orne et al. (1972) and Woodsworth and Schlosberg
    (1954) agree that LD is a real-life situation is
    an art rather than a science.
  • The fact that most polygraphists are not trained
    psychologists has also contributed to the lack of
    scientific validation of techniques.

11
  • Kleinmuntz and Szucho (1984) accuse psychologists
    of having neglected polygraphs lie detection.
  • They contend that the procedure is a psychometric
    measure that has not demonstrated reliability or
    validity.
  • Kleinmuntz and Szucho have also reported studies
    in whish 37-50 of innocent people were
    classified as lying or guilty

12
  • Raskin, Barland and Podlesay (1977) completed a
    study that examined reliability and validity of
    polygraph techniques and found that using CQT and
    GKT techniques were nearly 90 accurate when
    properly conducted.
  • Ben-Shakar and Furedy (1990) examined GKT
    validity studies and found an accuracy rate of
    84 for guilty subjects and 94 for innocent
    subjects.

13
  • Raskin and Hare (1978)
  • Addressed the notion of beating a polygraph
  • Used a sample of 48 inmates, half of which were
    diagnosed psychopaths
  • Half of each group were guilty of taking 20 in a
    mock crime, the other half was innocent.
  • Electrodermal activity, cardiovascular response
    and respiration rates were measured.

14
  • The results yielded 88 accuracy, 4 wrong and 8
    inconclusive
  • Psychopaths were accurately detected
  • Psychopaths also showed evidence of stronger
    electrodermal responses and hear rate deceleration

15
  • The debate has continued, while polygraph testing
    is still being used in criminal investigations
    and is also used for job screening processes for
    a multitude of jobs.

16
Laboratory Studies
  • Advantage truthfulness in response can be
    controlled and compared to the psychological
    response given.
  • Thackray Orne, 1968
  • Subjects told they were being interrogated as if
    they were spies and were given a list of code
    words
  • Experimenter didnt know these words, but asked
    questions relevant to the words
  • Observed skin conductance, skin potentials,
    systolic blood pressure, finger volume, and
    respiration
  • Found SCR was the best single way to determine
    deception. Also found that systolic blood
    pressure and respiration amplitude had
    inconsistent results.

17
  • SCR
  • Other follow up studies have agreed with the
    previously mentioned study
  • Disputed- some believe SCR is too sensitive, and
    that it cant discriminate between relevant and
    irrelevant questions in amotional interrogations.

18
  • GKT
  • Assumes suspects are aware of relevant
    information, and will show greater physiological
    responses to relevant items.
  • Bradley Warfield-1984
  • Three groups of innocent subjects were given the
    same crime related information as a group of
    guilty subjects in a mock crime
  • Higher response in guilty subjects, thus, those
    attempting to deceive were detected accurately
  • Motivation to deceive is a factor in detection of
    deception
  • Alcohol intoxication reduced detectability with
    detection scores based on EDA in mock crime
    (1984).

19
Use of Countermeasures
  • A way to alter physiological response and
    contribute to erroneous decisions regarding
    guilt.
  • Examples self-induced pain, muscular movements,
    changes in breathing during critical questions,
    thinking about relaxing or exciting scenes.

20
Countermeasures and CQT/GKT
  • Honts, Hodes, Raskin- 1985
  • Guilty subjects in mock crime could produce
    enhanced responses to control questions, and were
    then deemed innocent.
  • Elad Ben-Shakar- 1991
  • Manipulated attention level and type of mental
    countermeasure to determine effect on GKT
    measured by SCR
  • Attention Levels High (motivational
    instructions, verbal responses, monetary rewards)
    and Low (no verbal responses, no reward)
  • Mental Measures Continuous (counting sheep
    during entire procedure), Item-specific (counting
    1-10 each time a relevant item was presented),
    and Neutral.
  • High attention- enhanced response to relative
    stimuli.
  • Continuous measure- diverted attention and
    lowered detection rates
  • Item-specific- increased response towards
    relative items.

21
Ways to Study Deception
  • EDA
  • Respiration
  • Pulse amplitude
  • Pulse volume
  • Heart rate
  • Podlesny Raskin- 1977
  • Muscle activity
  • Ocular activity
  • Pupil diameter
  • EEG
  • Voice analysis (found not accurate, Kubis 1973
    Horvath 1978)

22
P300
  • Farwell Donchin- 1991
  • 20 subjects in one of two spy scenarios
  • Tested on knowledge of both scenarios by being
    asked questions target, probes, or irrelevant
  • Subjects pushed one switch for targets and
    another for probes and irrelevant questions
  • Larger P300s produced for target questions, P300s
    produced for probes when related to the known
    scenario, no P300s for irrelevant questions
  • Whenever a decision on truth/lie could be made by
    the P300 it was accurate

23
P300
  • Rosenfeld, Angell, Johnson, Quan- 1991
  • CQT procedure used
  • 32 males randomly assigned to guilty and innocent
    groups
  • Measures P300 responses, 89 accurate
  • Johnson and Rosenfeld-1992
  • Subjects presented with list of eight antisocial
    acts and one target word
  • Subject required to press button when they
    recognized the target word
  • ERP obtained, truth then obtained from subjects
  • P300 response was 87 accurate

24
P300
  • Built-in control responses to targets by innocent
    and guilty subjects
  • Lack of P300 due to the stimulus being irrelevant

25
Lie Detector Test
  • Furedy-1986
  • specific effects approach must be used to
    evaluate polygraph
  • This would require better deception detection by
    the examiner
  • Issue of accuracy in polygraph charts
  • Furedy- 1993- CQT Dilemma
  • Ethical dilemmas
  • Some innocent classified as deceptive
  • Those classified as non-deceptive never debriefed
  • Wanted to end the use of this technique
  • (other debated this saying that to abandon the
    CQT would be contrary to scientific evidence and
    not in the interest of society)

26
Vigilance
  • OHanlon Kelly- 1977
  • Prolonged night driving (200 minutes)
  • Performance of 41 males, EEG and HR taken
  • Frequency of drifting out of lane
  • Better drivers had higher heart rate activity and
    lower heart rate variability
  • Low arousal levels and extreme erratic driving.
    Often drivers didnt realize

27
Vigilance
  • Beh-1990
  • Heart activity examined
  • Subjects were either high or low scorers on a
    need for achievement scale
  • Detection of 60 visual signals over 30 minutes
  • No difference in groups prior to vigilance
  • Vigilance performance, measured in decision and
    movement time, was significantly superior in high
    scorers
  • Concluded those with higher achievement
    motivation use greater mental effort in task
    performance which results in cardiovascular
    motivation

28
Vigilance
  • Boucsein Ottmann- 1996
  • Night shift work and noise
  • Participants worked day shift (8am-6pm) or night
    shift (8pm-6am) for a five day period.
  • Worked under either simulated traffic noise or no
    noise.
  • Skin conductance and heart rate measured
  • Higher skin conductance, heart rate and reaction
    time during day shift with no dramatic decrease
    in shift.
  • Low skin conductance, heat rate and reaction time
    to night shift workers, with dramatic decrease
    during second half of shift. Noise was slightly
    helpful in maintaining heart rate. (Note these
    workers were not accustomed to night shift work.)

29
Cerebral Blood Flow fMRI
30
Cerebral Blood Flow
  • Relatively constant 750 ml per minute (15 of
    total cardiac output at rest)
  • Not normally influenced by sympathetic nerve
    activity
  • Except when MAP rises to about 200 mmHg,
    sympathetic nerves cause vasoconstriction.
  • - help protect small, thin-walled arterioles
    from bursting under the pressure, thus prevent
    cerebrovascular accident.

31
Cont
  • Regulated by local intrinsic mechanism
    (autoregulation) through
  • Myogenic mechanisms
  • Metabolic mechanisms

32
Cont
  • Myogenic
  • Occurs when there is variation in systemic
    arterial pressure
  • Blood pressure?, cerebral arteries automatically
    dilate BP?, arteries constrict
  • Cerebral vessels are also sensitive to CO2
    concentration of arterial blood
  • Hypoventilation CO2 rise, arterioles dilate
  • Hyperventilation CO2 falls, arterioles
    constrict, hence blood flow decrease resulting in
    dizziness.

33
Cont..
  • Metabolic Regulation
  • Particular brain regions that are most active
    receive an increased blood flow
  • Hyperemic blood flow of the active brain regions
    actually exceeds the aerobic requirements of the
    active neurons
  • Highest metabolic activity receive the most blood
  • Areas of the brain that control specific
    processes have been mapped by the changing
    patterns of blood flow that result when these
    areas are activated

34
fMRI
  • Enables researchers and physicians to visualize
    parts of the brain that are active during
    specific tasks
  • This techniques highlights fast-moving blood, and
    blood moves fastest in those parts of the brain
    that are working hardest.
  • Active regions glow more brightly than inactive
    regions in fMRI

35
Detection through Cerebral Blood Flow
  • Scalp-recorded event-related potentials (ERPs)
    have also been used in the study of deception.
  • Series of voltage oscillations reflect the
    neuronal activity associated with sensory, motor,
    or cognitive event, provide high temporal
    resolution but their source in the brain cannot
    be localized (Hillyard and Anllo-Vento, 1998).
  • Amplitude and latency of the P-3 have been
    associated with deception, suggesting that the
    cognitive differences between lying and telling
    the truth could be associated with changes in
    other correlates of brain activity, such as
    regional cerebral flow (rCBF) (Holden, 2001
    Rosenfeld, 2001).

36
Cont
  • Chen, 1999 indicated that unlike the ERP, fMRI
    is sufficient to localize changes in rCBF related
    to regional neuronal activity during cognition
  • Langleben , et al. (2002) reason if other
    studies could find differences in evoked
    potentials between the guilty and innocent in
    the CQT that perhaps using fMRI to detect blood
    flow in the brain could detect the guilty and
    innocent as well.

37
Cont
  • Blood oxygenation level-dependent fMRI contrasts
    between deceptive and truthful responses were
    measured with a 4 Tesla scanner in 18
    participants performing the GKT and analyzed
    using statistical parametric mapping.
  • They found that increased activity in the
    anterior cingulate cortex (ACC), the superior
    frontal gyrus (SFG), and the left premotor,
    motor, and anterior parietal cortex was
    specifically associated with deceptive responses.

38
Cont
  • In conclusion, Langleben et al. indicated that
    deception was associated with activity in the
    anterior cingulate cortex and the superior
    frontal gyrus using fMRI.
  • Since deception-induced mood and somatic states
    may vary across individuals, a search for a
    marker of deception independent of anxiety or
    guilt is needed, and using fMRI to detect
    regional brain activity elicited by the
    inhibition of the truth response during
    intentional deception could serve as such a
    marker.

39
  • http//static.howstuffworks.com/gif/lie-detector-p
    arts.jpg
  • Langleben DD, Schroeder L, Maldjian JA, Gur RC,
    McDonald S, Ragland JD, O'Brien CP, Childress AR.
    (2002). Brain activity during simulated
    deception an event-related functional magnetic
    resonance study. NeuroImage 15, 727732.
  • Fox, S.I. (2006). Human Physiology. 9th edition.
    New York NY. McGraw Hill
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