title: The first independent study on the complex trial protocol version of the P300-based concealed information test: Corroboration of previous findings and highlights on vulnerabilities.
abstract: More than a dozen studies of the Complex Trial Protocol (CTP) version of the P300-based Concealed Information Test have been published since its introduction (Rosenfeld et al., 2008), and it has been fairly consistently proven to provide high accuracy and strong resistance to countermeasures (Rosenfeld et al., 2013). However, no independent authors have verified these findings until now. In the present, first independent study, we corroborate the accuracy and countermeasure-resistance of the CTP, when the probe item (critical presented information, e.g., crime detail; P) vs. all irrelevant items (Iall) comparison is used for classifying participants as guilty or innocent, but we also show that the CTP is severely vulnerable to countermeasures, when the P vs. the irrelevant item with the largest P300 responses (Imax) comparison is used. This latter measure can be defeated by creating "oddball" items among the irrelevant items (through targeting them with covert responses), and thereby making their P300 responses statistically indistinguishable from those of the probe item. Practical implications are discussed.
authors.affiliation: Department of Cognitive and Neuropsychology, Institute of Psychology, Faculty of Arts, University of Szeged, Egyetem u. 2, 6722 Szeged, Hungary.
authors.forename: Gáspár
authors.initials: G
authors.lastname: Lukács
authors.affiliation: Brain Imaging Centre, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok körútja 2, 1117 Budapest, Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Weiss
authors.affiliation: Department of Cognitive and Neuropsychology, Institute of Psychology, Faculty of Arts, University of Szeged, Egyetem u. 2, 6722 Szeged, Hungary.
authors.forename: Vera Daniella
authors.initials: VD
authors.lastname: Dalos
authors.affiliation: Department of Cognitive and Neuropsychology, Institute of Psychology, Faculty of Arts, University of Szeged, Egyetem u. 2, 6722 Szeged, Hungary.
authors.forename: Tünde
authors.initials: T
authors.lastname: Kilencz
authors.affiliation: Department of Cognitive and Neuropsychology, Institute of Psychology, Faculty of Arts, University of Szeged, Egyetem u. 2, 6722 Szeged, Hungary.
authors.forename: Szabina
authors.initials: S
authors.lastname: Tudja
authors.affiliation: Department of Cognitive and Neuropsychology, Institute of Psychology, Faculty of Arts, University of Szeged, Egyetem u. 2, 6722 Szeged, Hungary; Department of Psychology, University of Tromsø, Huginbakken 32, 9037 Tromsø, Norway. Electronic address: gaborcsifcsak@yahoo.co.uk.
authors.forename: Gábor
authors.initials: G
authors.lastname: Csifcsák
mesh_terms: D000328:Adult; D008192:Deception; D004569:Electroencephalography / Q000379:methods*; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D006801:Humans; D008014:Lie Detection; D008297:Male; D009483:Neuropsychological Tests / Q000592:standards*; D021641:Recognition, Psychology / Q000502:physiology*; D055815:Young Adult
keywords: Complex trial protocol; Concealed information test; Countermeasure; Memory detection; P300; Verification