Cardiographic Detection of Deception

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Cardiographic Detection of Deception

• Jessica, Hieu, Pat

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Detection of DeceptionHistorical Background
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• 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.

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• 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.

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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.

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arts.jpg
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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.

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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.

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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.

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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

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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.

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• 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

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• 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.

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• 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.

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• 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

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• 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.

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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.

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• 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.

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• 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).

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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.

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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.

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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)

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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

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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

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P300

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

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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)

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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

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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

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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.)

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Cerebral Blood Flow fMRI
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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.

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Cont

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

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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.

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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

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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

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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).

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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.

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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.

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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.

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• 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