Ocular-Motor Methods for Detecting Deception: Effect of Countermeasures
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Masaryk University Faculty of Arts Department of Psychology Monika Kupcová Ocular-Motor Methods for Detecting Deception: Effect of Countermeasures. Supervisor: prof. PhDr. Tomáš Urbánek, Ph.D. Consultant: John C. Kircher, Ph.D. 2017 I hereby declare that I wrote this thesis on my own. I have acknowledged all sources used and have cited these in the reference section. In Brno, 30.11.2017 ……………………………… Monika Kupcová ACKNOWLEDGEMENTS I would first like to thank professor John C. Kircher who has been a wonderful mentor. I am beyond grateful for his immense knowledge and for his guidance through writing this thesis: encouraging my ideas, helping me with the software, guiding me through the data analysis, and much more. I have asked him countless questions and I cannot thank enough for every answer I have always been given. I would like to thank professor Tomáš Urbánek for his support of my ideas from the very beginning. The door to his office was always open whenever I ran into a trouble spot or had a question. I must express deep gratitude to my parents for providing me with unfailing support and continuous encouragement throughout my years of study and through the process of writing this thesis. This would not have been possible without them. Thank you. Last, but not least, I would like to thank all the participants that participated in the experiment and to all the undergraduate students who served as the secretary confederates in the experiment. Table of Contents INTRODUCTION ............................................................................................................... 5 I. THEORETICAL PART .............................................................................................. 7 Deception detection ....................................................................................................... 7 Lay people vs. professionals ................................................................................... 8 Application of deception detection ......................................................................... 9 History of deception detection ................................................................................ 9 Addressing the Ground Truth Issue ...................................................................... 11 Approaches to detect deception ............................................................................ 13 1.5.1 Physiological lie detection: The Polygraph ................................................... 14 1.5.2 Neuroimaging- based lie detection ................................................................ 16 1.5.3 Verbal lie detection tools: Statement validity analysis, Reality monitoring and Scientific content analysis ........................................................................................... 17 1.5.4 Non-verbal lie detection ................................................................................. 18 The Ocular- Motor Deception Test (ODT) .................................................................. 21 Vision .................................................................................................................... 22 2.1.1 Anatomy and physiology of the eye .............................................................. 22 Physiological and psychological bases of pupil dilation ....................................... 23 2.2.1 Light reflex .................................................................................................... 24 2.2.2 Fatigue ........................................................................................................... 25 2.2.3 Pain ................................................................................................................ 25 2.2.4 Startle response and emotional arousal .......................................................... 25 2.2.5 Cognitive load ................................................................................................ 27 Deception and cognitive load ................................................................................ 29 Pupil dilation during deception: arousal vs. cognitive load .................................. 31 Reading behaviors during deception ..................................................................... 33 Countermeasures .......................................................................................................... 33 Current research on the ocular-motor methods for detecting deception ...................... 38 II. EMPIRICAL PART .................................................................................................. 43 Present study ................................................................................................................ 43 METHODS ................................................................................................................. 45 Overview of the Design ........................................................................................ 45 Participants ............................................................................................................ 46 Procedures ............................................................................................................. 47 Materials ................................................................................................................ 49 2.4.1 The Ocular-Motor Deception Test ................................................................. 49 2.4.2 The post-test questionnaire ............................................................................ 50 2.4.3 The information documents ........................................................................... 51 Apparatus .............................................................................................................. 52 Data Collection and Analysis ................................................................................ 52 RESULTS ................................................................................................................... 53 Pupil measures ...................................................................................................... 54 Countermeasures ................................................................................................... 59 Additional results .................................................................................................. 62 DISCUSSION ............................................................................................................. 64 Limitations of the study ........................................................................................ 67 Implications and future directions ......................................................................... 69 Conclusion ................................................................................................................... 70 References .................................................................................................................... 71 INTRODUCTION Several government agencies and private companies, routinely conduct credibility assessments to test job applicants and screen current employees. In many countries, criminal investigations also have an option to use a polygraph examination of the suspects. In the Czech Republic, since 1984 for instance, there is one center for physiological detection of deception within police investigations: Kriminalistický ústav Praha. Apart from polygraph, a voice analysis is used to assess credibility and altogether it is called the “Physio-detection examination” (Gillernová & Boukalová, 2006). The polygraph is the most widely used method of credibility assessment (Honts, 2014). However, a National Research Council (NRC) in a review of the scientific evidence on the polygraph had several criticisms toward polygraph examination, especially its use for pre-employment screening. The NRC highlighted the need for “an expanded research effort directed at methods for detecting and deterring major security threats, including efforts to improve techniques for security screening . .” (National Research Council, 2003, p. 8). More recently, a cognitive approach to detecting deception became relevant. The notion is that lying requires more cognitive effort than telling the truth (e.g. Vrij et al., 2008; Vrij, Granhag, & Porter, 2010). Vrij (2004) suggested that the right question to ask when we try to reveal deception in practice might not be “Is the person lying?”. As discussed throughout this paper, lying is cognitively more demanding than truth- telling. Therefore, instead, we need to consider asking “How hard is the person thinking?” Cook and her colleagues (2012) introduced a new method to detect deception, the Ocular-Motor Deception Test (ODT). The ODT evaluates pupillary responses and reading behavior that occur while a person reads and responds to statements about their possible involvement in a mock-crime. This method has the potential to substitute polygraph examinations in security screenings as it is fast, non-intrusive and relies on cognitive indicators of deception rather than solely on physiological indicators of sympathetic activation. The issue in any kind of credibility assessment is that there is usually a lot at stake for the person that is interviewed. Naturally, people attempt to develop techniques and strategies which would lead to an examiner’s conclusion of their innocence. Those deliberate techniques used by guilty people to defeat the deception test are called ‘countermeasures’