Schachter-Singer two-factor theory
Explanation:
A polygraph is a lie-detector test which uses certain devices and procedure to measure or record various physiological parameters like blood pressure, heart rate, respiratory rate, skin conductivity etc at the same time when the subjective person answers to a series of questions asked.
The principle is that a person’s or examinee’s physiological or clinical parameters like blood pressure or heart rate can accelerate, stay stable, or may even go down in response to the questions asked. Depending upon these changes, the examinee can be assessed whether he/she is telling a lie or truth about something asked.
The Schachter-Singer two-factor theory of emotions states that emotions are dependent on two factors – physiological arousal and cognitive label.
According to this, an environmental stimulus gives rise to a physiological reaction or arousal which then leads to cognitive appraisal of the emotion.
Thus the theory of polygraph is based on Schachter-Singer’s emotional theory.