title: The P300-based, complex trial protocol for concealed information detection resists any number of sequential countermeasures against up to five irrelevant stimuli.
abstract: We previously tested the P300-based Complex Trial protocol for deception detection against 2 and 4 countered of 4 irrelevant stimuli. The protocol detected 90-100% of these subjects with <10% false positives. We have also shown that Reaction Time (RT) to the first trial stimulus is increased (group effect) with countermeasure use. We also reported a new P900 component associated with countermeasure use when 2 of 4 irrelevants are countered. In the present study we report data from 4 new groups and re-present for comparison previously collected data to have 7 groups: an innocent control, a guilty group not using countermeasures, and 5 guilty/countermeasure groups who counter from 1 to all 5 stimuli presented (4 irrelevants plus a probe). Subjects were detected at rates varying from 92 to 100% in the 6 guilty groups (n = 12 or 13 per group). There was 1 false positive in 13 innocent subjects. Additionally, 41 of 60 CM users were identified with RT as using countermeasures. P900 appeared in the 2 groups using 2 and 3 countermeasures.
authors.affiliation: Department of Psychology, Northwestern University, Evanston, IL, USA.
authors.forename: Elena
authors.initials: E
authors.lastname: Labkovsky
authors.forename: J Peter
authors.initials: JP
authors.lastname: Rosenfeld
mesh_terms: D000328:Adult; D008192:Deception; D004569:Electroencephalography / Q000295:instrumentation / Q000379:methods*; D004585:Electrooculography / Q000295:instrumentation / Q000379:methods*; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D005189:False Positive Reactions; D005260:Female; D006167:Guilt; D006801:Humans; D008014:Lie Detection / Q000523:psychology*; D008297:Male; D011930:Reaction Time / Q000502:physiology*; D012680:Sensitivity and Specificity; D055815:Young Adult