Voice-based credibility assessment:

Overview of the research

For over forty years, the polygraph has been the most reliable and valid means of detecting whether someone was being deceptive.  Unfortunately, the polygraph is very invasive, requires sophisticated equipment, and extensive operator training.  One alternative to the polygraph that has been the subject of recent investigations is to use changes in voice as a basis for detecting deception.  The rationale behind this approach is that stress associated with deception will produce changes in acoustic parameters of the voice and these can be detected by computer algorithsm.  Our work in this area has focused on:

1. Evaluating the reliability and validity of several commercially available voice-based systems for detecting deception
2. Conducting basic research into the vocal parameters that are most associated with deception
3. Trying to improve current algorthims for using changes in vocal parameters as a basis for detecting deception.