W7 Detecting Deception

Question 1

What is deception?

Answer 1

A successful or unsuccessful attempt, without forewarning, to create in another a belief which the communicator considers to be untrue (Vrij, 2000).

Question 2

What are the key components of deception?

Answer 2

Intent, no forewarning, and success is not relevant.

Question 3

What are the types of deception?

Answer 3

Falsifications, distortions/exaggerations, and omissions.

Question 4

What are the three ways to detect a liar?

Answer 4

1. Physiological/formal techniques (e.g., polygraph).
2. Nonverbal/body language cues.
3. Verbal cues (content of the lie, active interviewing).

Question 5

What does a polygraph measure?

Answer 5

Heart rate, blood pressure, breathing (rate & depth), and Galvanic Skin Response.

Question 6

What emotional responses are linked to lying according to Ekman (1989, 1992)?

Answer 6

Guilt, fear, and excitement.

Question 7

What is the Control Question Technique (CQT)?

Answer 7

It compares physiological responses to neutral, relevant, and control questions to determine truthfulness.

Question 8

What are the problems with the Control Question Technique?

Answer 8

Assumes different physiological responses for innocent vs. guilty suspects and raises ethical concerns about deceiving suspects.

Question 9

What does the Guilty Knowledge Test (GKT) assess?

Answer 9

It assesses whether a suspect recognizes details that only a guilty person would know.

Question 10

What are the advantages and problems of the Guilty Knowledge Test?

Answer 10

Advantages: Better ethics than CQT. Problems: Limited applicability and knowledge ≠ guilt.

Question 11

What are the claims about the accuracy of the polygraph?

Answer 11

Claims of up to 99% accuracy, but statistics can be manipulated.

Question 12

What are countermeasures in the context of polygraphs?

Answer 12

Techniques to increase response to baseline items or decrease response to relevant items to avoid detection.

Question 13

What is thermal imaging based on?

Answer 13

Instantaneous anxiety response, with variable accuracy rates.

Question 14

What is “brain-fingerprinting” using ERP analysis?

Answer 14

Measures changes in P300 waveform to detect recognition of relevant items among irrelevant ones.

Question 15

What are the pros and cons of using fMRI for lie detection?

Answer 15

Pros: High accuracy rates and measures complex brain activity. Cons: Lack of replication, cost, and ethical concerns.

Question 16

What is the overall summary regarding polygraph testing and other techniques?

Answer 16

Polygraph tests (CQT and GKT) have issues with false positives and negatives, and other techniques raise questions about validity, effectiveness, and ethics.