He was credited as the creator of the systolic blood pressure test used, and employed it in an attempt to detect deception during questioning, using standard blood pressure cuff stethoscope.

It is defined as a scientific instrument purposely designed to record the psycho- physiological changes that occur within the body especially of lying when questioned.

The scientific method of detecting deception with the aid of

an scientific instrument.

The word polygraph is a combination of two words “poly” which means:______

He studied fear and its influence on the heart in which his observation subsequently formed the basis of detection technique.

He employed the first scientific instrument to detect deception, which was known as hydrosphygmograph, an instrument to measures changes in pulse and blood pressure when suspects were asked about their involvement in a particular offense.

He described how he recorded the subject’s breathing using a Maley Pneumograph, noting the changes in respiration-expiration ration during deception.

He is the person introduced the word association test in 1879.

He is the person believed that the origin of the galvanic skin phenomenon was under the influence of the exciting expressions and that the will has no effect upon it.

He is an English clinician and cardiologist, constructed the clinical polygraph in 1892, an instrument used in medical examination.