Design a method for removing the cuff of polygraphy system in lie detection testusing MLP neural network

Subject Areas : Information Technology in Engineering Design (ITED) Journal

Mohammad Amin Younessi Heravi ¹ , Mahdi Azarnoosh ²

1 - Department of Basic Sciences, School of Medicine, North Khorasan University of Medical Sciences(NKUMS), Bojnurd, Iran.
2 - Department of Biomedical Engineering, Mashhad Branch, Islamic Azad University Mashhad, Iran

Received: 2017-06-19 Accepted : 2017-06-19 Published : 2014-08-23

Keywords:

Abstract :

Psychophysiologic verity test is a topic which is used widely in the world. Polygraphy system is usedfor recording the Psychophysiologic signals of a person in these tests and a cuff is used for measuringrelative changes of the arterial blood pressure and recording the velocity and power of the heart pulsein polygraph system. But the problem is that using cuff in various tests brings undesirable conditionsfor the body. The aim of this paper is to present a method for removing cuff in a way that desiredinformation is resulted in another way. This goal is followed by using arterial photoplethysmograhy.In order to do that, a model is presented which uses arterial volume to estimate blood pressure changessignal. This model was identified with MLP neural network. The output of this model is comparedwith blood pressure changes signal in three levels of signal, feature and classification. Reliability ofthe model was evaluated by presenting appropriate assessment criterions. The results were gained withthe 9.8% relative error, 4.4% relative error power and 80% accuracy of lie recognition in signalsassessed for blood pressure changes.According to the findings, the new method introduced in thisstudy has a comparable accuracy of results to the results of former methods while offering a morecomfortable recording and less diagnostic costs. This new method can be suggested for use as a liedetecting system.