A system based on acquisition and processing of electrocardiographic (EKG) signals from two fingers has been proposed as a means of determining whether a person is answering questions evasively. The system — in effect, a "lie detector" of sorts, would be used to gauge prospective passengers' responses to questions at airport security checkpoints. The person to be interrogated would be required to put one finger from each hand onto two metal strips on a counter and would be instructed to relax and wait for the system to indicate that it is ready. Then a security person would ask the passenger a set of standard security questions. EKG signals acquired through contact with the fingers would be processed by an algorithm that would extract a single-value measure of the level of stress in the interrogated person. This measure would be used to determine whether the system should display a green or a red light to signify that the person is or is not, respectively, telling the truth. It has also been conjectured that the system may be useful for communicating with a person who is in a coma and, hence, unable to speak.

This work was done by Daniel Oldham of Glenn Research Center.

Inquiries concerning rights for the commercial use of this invention should be addressed to NASA Glenn Research Center, Commercial Technology Office, Attn: Steve Fedor, Mail Stop 4-8, 21000 Brookpark Road, Cleveland Ohio 44135. Refer to LEW-17441-1.


NASA Tech Briefs Magazine

This article first appeared in the February, 2004 issue of NASA Tech Briefs Magazine.

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