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Educing Information: Interrogation - National Intelligence University

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and potentially could interfere with the desired signal. Body movements such<br />

as rocking or swaying could be potential countermeasures to this technology.<br />

Sophisticated signal processing is required to extract the desired signal from<br />

the noise. Potential solutions to these movement countermeasures are being<br />

researched (Geisheimer and Greneker, 2000; Geisheimer and Greneker, 2001).<br />

RVSM transmits at a frequency of 24.1 GHz, where skin reflects<br />

approximately 73% of the wave; the rest of the energy is quickly dissipated in the<br />

first several millimeters of the body. Given radiation safety concerns, the Federal<br />

Communications Commission (FCC) radio frequency exposure regulations have<br />

set a maximum permissible exposure level of 1 mW/cm 2 averaged over thirty<br />

minutes for a transmission frequency of 24.1 GHz. These exposure limits can<br />

be met at a distance of 12.85 cm from the RVSM transmitter (Geisheimer and<br />

Greneker, 2000; Geisheimer and Greneker, 2001).<br />

Because RVSM technology measures some of the same psychophysiological<br />

responses as the polygraph, it is subject to the same criticisms (see Section 2.1).<br />

Due to the lack of published results in the literature, it appears that researchers<br />

have not yet explored this technology in the context of detecting deception. Given<br />

this lack of scientific validation, RVSM is probably not ready to be deployed.<br />

Facial Expressions<br />

Human emotional responses can be recognized through facial expressions<br />

(Ekman, 1994; Izard, 1994). According to Ekman (1972), a specific set of facial<br />

expressions appears to be generated by the emotions of anger, disgust, fear,<br />

happiness, sadness, surprise, and to a lesser degree contempt, embarrassment,<br />

interest, pain, and shame. Ekman (1972) further states that these emotions are<br />

universally generated and recognized across all cultures. Ekman and Friesen<br />

(1978) developed the Facial Action Coding System (FACS) to measure all visible<br />

facial muscle movements, not just those presumed to be related to emotion, as well<br />

as head and eye movements. In approximately 100 to 300 hours, an individual<br />

can learn to code facial expressions based on the characteristic pattern of bulges,<br />

wrinkles, and movements for each facial Action Unit (AU), as well as to code the<br />

intensity of each AU. Ekman and Friesen (1978) identified forty-four AUs that<br />

can occur singly or in complex combinations.<br />

A review of the literature shows that research into automatic recognition of<br />

FACS AUs is limited (Tian et al., 2003). Deception detection experiments have<br />

only coded FACS AUs manually (Ekman, 1985; Ekman et al., 1991; Frank and<br />

Ekman, 1997). Despite this, the current state of the art is briefly reviewed here. In<br />

2001, two teams (Carnegie Mellon <strong>University</strong> and the <strong>University</strong> of Pittsburgh —<br />

referred to as CMU/Pitt, and the <strong>University</strong> of California, San Diego, and the<br />

Salk Institute — referred to as UCSD/Salk) were tasked to quantitatively analyze<br />

spontaneous facial expressions to estimate AUs (Cohen et al., 2001; Bartlett et<br />

al., 2001). Both teams independently developed a non-intrusive automatic facial<br />

expression recognition system capable of handling non-frontal pose, moderate<br />

out-of-plane head motion, and moderate occlusion from head motion, eyeglasses,<br />

gestures, talking, subtle facial actions, and rapid facial motion. It should be noted<br />

68

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