Abstract

The human brain has an extraordinary capacity to “pre-consciously locate” stimuli that are salient to it. A particularly compelling demonstration is Rapid Serial Visual Presentation (RSVP), in which the vast majority of stimuli presented are not consciously perceived, but ones that are salient breakthrough into awareness [Bowman,13]. Importantly, we have shown that it is possible to determine which stimuli in an RSVP stream an individual finds salient by monitoring the electrical response from their brain. We do this by looking for a P3 component with EEG . This gives us a means to present a lot of stimuli very rapidly to an individual and determine which they find salient from their brain activity. We call this the Fringe-P3 method, since stimuli are presented on the “fringe” of awareness.

I will discuss a number of applications of this Fringe-P3 method that cross a number of disciplines, including Computing and Forensics. In particular, I will consider how the method can be used as an alternative to image processing methods in image triage, and how it can provide a brain-computer interface [Chennu,13], i.e. be used to control a computer directly from brain activity. We will particularly focus on the method’s use as a concealed information test in deception detection, where we have shown it to be resistant to countermeasures [Bowman,14]. Finally, if time permits, I will discuss the computational statistics methods we use in our EEG analyses, which are focussed on Monte Carlo resampling and Fisher combining.

[Bowman,13] Bowman, H., Filetti, M., Janssen, D., Su, L., Alsufyani, A., & Wyble, B. (2013). Subliminal salience search illustrated: EEG identity and deception detection on the fringe of awareness. PloS one, 8(1), 1-21.

[Bowman,14] Bowman, H., Filetti, M., Alsufyani, A., Janssen, D., & Su, L. (2014). Countering countermeasures: Detecting identity lies by detecting conscious breakthrough. PloS one, 9(3), e90595.

[Chennu,13] Chennu, S., Alsufyani, A., Filetti, M., Owen, A. M., & Bowman, H. (2013). The cost of space independence in P300 -BCI spellers. J. Neuroeng. Rehabil, 10.