Subliminal Salience Search Illustrated: EEG Identity and Deception Detection on the Fringe of Awareness

Abstract

We propose a novel deception detection system based on Rapid Serial Visual Presentation (RSVP). One motivation for the new method is to present stimuli on the fringe of awareness, such that it is more difficult for deceivers to confound the deception test using countermeasures. The proposed system is able to detect identity deception (by using the first names of participants) with a 100% hit rate (at an alpha level of 0.05). To achieve this, we extended the classic Event-Related Potential (ERP) techniques (such as peak-to-peak) by applying Randomisation, a form of Monte Carlo resampling, which we used to detect deception at an individual level. In order to make the deployment of the system simple and rapid, we utilised data from three electrodes only: Fz, Cz and Pz. We then combined data from the three electrodes using Fisher's method so that each participant was assigned a single p-value, which represents the combined probability that a specific participant was being deceptive. We also present subliminal salience search as a general method to determine what participants find salient by detecting breakthrough into conscious awareness using EEG.

The cost of space independence in P300-BCI spellers

“…These could be used to constrain the structure of RSVP streams, such that, for example, a priori frequently occurring letters do not appear in one another’s blink window and the next instance of an item does not arise within the repetition blindness window of a previous instance. Indeed, many of the issues relating to presentation format arise generally across applications of such ‘subliminal salience search’ mechanisms [49], and their empirical resolution could have broad impact. This mechanism could be applied in lie detection [49], information retrieval, image triage [50] and stimulus rich information presentation [51].…”

“…Indeed, many of the issues relating to presentation format arise generally across applications of such ‘subliminal salience search’ mechanisms [49], and their empirical resolution could have broad impact. This mechanism could be applied in lie detection [49], information retrieval, image triage [50] and stimulus rich information presentation [51]. Further understanding of presentation parameters and their influence on EEG responses could benefit all such applications.…”

Data‐driven region‐of‐interest selection without inflating Type I error rate

“…ERP waveforms were derived from grand averages in previous studies in our group: P300 (fake condition in Bowman et al, 2013) and N170 (unpublished data).…”

Latency as a region contrast: Measuring ERP latency differences with Dynamic Time Warping

“…In order for our analysis to be reliable we used signals, to represent the first condition, that were obtained from a real EEG experiment (Bowman et al, 2013). In particular, we generated ERP signals from a deception detection experiment, where EEG data were recorded from 15 participants.…”

“…The methods were examined on two different channels Fz and Pz and the analysis was focused on the P3a and P3b components respectively, as in the original analysis. The steps followed in each channel were the same and consisted of firstly generating the ERP signal following all the preprocessing steps described in Bowman et al (2013). The signal ( for channels Fz and Pz respectively), which was the ERP for the probe condition (generated from the grand average across participants), was then smoothed by interpolating between a set of peaks.…”