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Forensic Applications

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Cognitive Engineering, LLC

Determining innocence of a criminal charge based upon interrogation and evidence can be a difficult and indeterminate process. Polygraphy is limited by reliance on peripheral manifestations of anxiety (skin conductance, heart rate, and respiration), which can to certain extents be circumvented.  Scalp-recorded event-related potentials (ERPs) reflect neuronal activity associated with a sensory, motor, or cognitive event. The P-300 wave of the ERP appears in response to rare, meaningful stimuli, and its amplitude and latency has been associated with deception (lying on the Guilty Knowledge Test, GKT). This suggests 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 blood flow Unfortunately, the ESP provides high temporal but no spatial resolution in the brain

Since deception-induced mood and somatic states may vary across individuals, a marker of deception independent of anxiety or guilt is important. Regional brain activity, manifest as a blood oxygenation level dependent (BOLD) response. elicited by inhibition of the truth response during intentional deception has been demonstrated to serve as such a marker.  Unlike the ERP, the spatial resolution of BOLD event-related (questioning) functional MRI neuroimaging is sufficient to anatomically localize changes in cerebral blood flow related to regional neuronal activity during cognition.

Langleben and colleagues (2002) studied fMRI contrasts between deceptive and truthful responses. Responses of 18 participants performing the GKT were measured and analyzed using statistical parametric mapping. They found that deceptive responses were associated with increased activity in the anterior cingulate cortex (ACC), the superior frontal gyrus (SFG), and the left premotor, motor, and anterior parietal cortex.   This indicated that cognitive differences between deception and truth have neural correlates that can be detected by fMRI.

Thought Suppression

Wyland and colleagues (2003) found that suppression of a particular thought, when compared to free-thought control condition, revealed greater activation in the anterior cingulated area of the brain. When the task of suppressing all conscious thoughts was compared to free-thought, a more distributed network of brain regions, including the anterior cingulate and the insula, was activated.

Visual Recognition

Soltnick and Schacter (2004) used fMRI to study truth and false visual recognition. They found a preferential truth recognition activity in early visual processing regions of the brain. In fact, their research implied that the sensory signal distinguishing truth from deception may not be accessible to conscious awareness, indicating that intentional deception can be identified.

Cognitive Engineering uses specifically developed imaging and analysis algorithms and customized interrogation protocols to fit the individual situation. Cognitive Engineering can apply these techniques for forensic purposes to individual circumstances.  We will be pleased to discuss how fMRI can be applied to your individual case circumstances.

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