College #4 - (Neuro)psychological methods of deception detection

Question 1

Deception

Answer 1

The act of making a false statement with the intention of having the statement believed to be true by another person.

Question 2

The polygraph

Answer 2

A form of psychophysical deception detection known as the lie detector. The polygraph measures respiration, electrodermal activity and blood pressure, these measures covariate with attention, stress and emotion. The polygraph is often used in combination with the control question test.

Limitations:

• You can be stressed by other reasons.
• Stresslevel depends on explanation examinator.

The polygraph detects deception at a rate better than chance, but with error rates that could be considered significant.

Question 3

Cognitive load theory

Answer 3

It is more cognitive demanding to lie than to tell the truth.

• You need to surprise the truth.
• You need to manage the consistency.
• You need to monitor own and others behavior.

Question 4

Meta-analysis with fMRI and PET techniques in 12 studies by Christ et al. (2009).

Answer 4

Research to neural correlates of deception.
- 13 regions were more active during lying than during truth telling (8/13 located in/near prefrontal cortex).

However, there is considerable variability in the studies; no single brain region was active during deception in all the studies.

Question 5

Socially interactive vs non-interactive deception paradigms

Answer 5

The anterior cingulate cortex, the posterior superior temporal gyrus and the angular gyrus were all more active during social interactive lies.

Question 6

Inverse inference problem

Answer 6

It is highly implausible that there is a single and simple deception network to be discovered. Showing that a region of the brain activates when a person is trying to lie does not prove that region of the brain is involved in deception (only correlation).

Question 7

Transcranial magnetic stimulation (TMS)

Answer 7

TMS is a non-invasive form of brain stimulation. A wire cell is placed above the skull and creates a pulsed magnetic field which activates a current in the brain region of interest.&raquo_space; In this way we can manipulate a certain brain region.

Stimulation to the midline parietal cortex substantially slowed (by 20%) by trials they were supposed to lie.
Limitations
- Results depend on circumstances
- Findings haven’t been replicated
- The slowing effect is only found on group level and on individual level.

Question 8

Guilty knowledge test

Answer 8

A test that doesn’t aim to measure deception, but memory/knowledge. You have remember a crime item&raquo_space; when crime item is seen, you see a P300 peak.

Question 9

Mock crime study

Answer 9

Subjects had to plan a much terrorist attack on the United States.

Results&raquo_space; 12/12 guilty-subjects identified by P300 peak, with no false-positives among the 12 innocent-subjects.

Limitation&raquo_space; Small sample size.

Question 10

Test of Memory Malingering (TOMM)

Answer 10

A 50-item recognition test designed for adults to discriminate between true-memory impaired patients and malingerers.

Question 11

Structural Inventory of Malingered Symptomatology (SIMS)

Answer 11

Cosists of 75 true-false items on five sub scales (low intelligence, affective disorders, neurological impairment, psychosis and amnestic disorders.