PowerPoint Presentation: Deception Detection Techniques and technologies Yifei Zhou Gilead cohort 4 Dec 12 2011 Truth Bias: Truth Bias Deception detection is very critical Deception detection is a difficult task Humans are poor lie detectors How to improve deception detection rate: How to improve deception detection rate Lie spotting training Familiarity with individual’s usual behavior patterns (baseline) Overcome some problems like requirement of vigilant observation from multiple channels Statement Analysis: Statement Analysis Statement analysis refers to a collection of methods for associating linguistic behavior with deception. Connection between deception and language demonstrate how word choice, sentence structure, amount of detail, and other factors can be used to detect truth from lies. Signs of Deception: Signs of Deception Reading the face Body Language Interactions and Reactions Emotional Gestures Contradiction Verbal Context and Content Other signs Reading the face: Reading the face Micro-expressions Reliable muscle patterns Blink rates Pupil Dilation Intuition Body Language: Body Language Limited and stiff physical expression, with few arm and hand movements. A person who is lying to you tend to avoid making eye contact. Hands touching their face, throat & mouth. Touching or scratching the nose or behind their ear. Not likely to touch his chest/heart with an open hand. Interactions and Reactions: Interactions and Reactions Defensive Uncomfortable facing his questioner/accuser Unconsciously place objects between themselves and you. Emotional Gestures Contradiction: Emotional Gestures Contradiction Timing is off between emotions gestures/expressions and words. Gestures/expressions don’t match the verbal. Statement Expressions are limited to mouth movements when someone is faking emotions (like happy, surprised, sad)instead of the whole face. Verbal Context and Content:
Verbal Context and Content Use your words to make answer a question. Liars sometimes avoid "lying" by not making direct statements. The guilty person may speak more than natural. Words may be garbled and spoken softly, and syntax and
may be off.
Other Signs: Other Signs Change subject of a conversation quickly Using humor or sarcasm to avoid a subject. Deception Detection technologies: Deception Detection technologies Brain Imaging Brain Waves Eye Tracking Facial action units Thermal imaging Voice stress analysis Laser-Doppler Vibrometry Brain Imaging/Brain waves: Brain Imaging/Brain waves Functional magnetic resonance imaging is a leading lie detection technology fMRI device can track the brain’s use of blood over time Event-related potentials (ERPs) are recorded by sensors placed on the scalp Reveal the timing and general location of electrical activity in the brain Eye Tracking/Facial Analysis: Eye Tracking/Facial Analysis Uses multiple IR cameras to track eye movement patterns Interpretation of automated of frame-by-frame facial expressions is useful during free-flowing conversations. Thermal Imaging : Thermal Imaging When someone is making something up on the spot, brain activity usually changes and you can detect this through the thermal camera Voice Stress Analysis : Voice Stress Analysis Non-Contact Live or recorded samples Laser-Doppler Vibrometry: Laser-Doppler Vibrometry Tracks changes/movement in the artery Can remotely track pulse and blood pressure, Muscle tension and Artery stiffness Deception Detection in Negotiation: Deception Detection in Negotiation Gather information from multiple sources and be prepared Signal your ability to obtain information Ask open-ended questions to collect facts Deception Detection in Negotiation (Cont’d): Deception Detection in Negotiation (Cont’d) Ask yes/no questions to assess behavior Set a trap to triangulate on the truth Look out for responses that do not answer the question you asked Multiple channels Bibliography: Bibliography http://www.blifaloo.com/info/lies.php http://www.apa.org/monitor/julaug04/detecting.aspx Lie spotting, 2010, Pamela Meyer, St Martin’s Press Lying and deception in everyday life, 1993, Michael Lewis, Guilford Press