Educing Information: Interrogation - National Intelligence University

seek measurements that are closer to the biophysical seat of decision making.
The field of neuroscience has long sought to “understand the biological basis of
consciousness and the mental processes by which we perceive, act, learn, and
remember” (Kandel, 2000, p. 5). Revolutionary improvements in neuroscientific
techniques, combined with the sophisticated signal processing techniques made
practical by advances in information processing technology over the past few
decades, have made it possible to observe the neurophysiological processes of the
brain itself with increasingly greater resolution in time and space.
This section reviews these advanced techniques for studying the relationship
between cognitive and neural processes. These include electroencephalography,
magnetoencephalography, positron emission tomography, functional magnetic
resonance imaging, near infrared spectroscopy, and transcranial magnetic
stimulation. Empowered by these techniques, some neuroscience researchers
have chosen to forgo the measurement of autonomic responses and seek instead
to correlate deception and brain neurophysiology.
Electroencephalography (EEG)
EEG measures the changes in the electrical field potentials produced by the
sum of the neural postsynaptic potentials in the brain by means of electrodes
placed on the surface of the skin covering the head and face. The changes
directly related to specific perceptual or cognitive events are called event-related
potentials (ERPs). EEG/ERP studies require sophisticated signal processing to
separate the ERP components from the ongoing baseline electrical waves and
consequently require substantial computing power. EEG laboratories in the early
1980s typically relied upon cumbersome, room-sized computers, while advances
in information processing technology have made EEG using desktop computers
a practical reality.
Investigations of EEG/ERP as a means for detecting deception date back to
the late 1980s. Rosenfeld et al. (1987) and Donchin and Farwell (1991) reported
success using EEG techniques to identify specific ERPs that were correlated to
the recognition of guilty knowledge. In 1991 the Central Intelligence Agency
(CIA) funded Farwell to further develop his technique, but chose not to continue
the funding after an independent panel reported in 1993 that the developer was
unwilling to release details of his approach, viewing them as proprietary. Further,
the CIA, Secret Service, and FBI considered the technique to be of limited value
because it was based on a guilty knowledge paradigm and was therefore useless
for screening applications (United States Government Accounting Office, 2001).
EEG-based deception detection research is ongoing (e.g., Rosenfeld et al., 2004;
Vendemia et al., 2003).
Potential
EEG-based approaches have the advantages of good temporal resolution,
equipment that is relatively portable (at least in comparison to some of the other
alternative technologies), and present few safety concerns. On the negative side,
the higher density electrode arrays used in some approaches are tricky and time-
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