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Neuronal dynamics underlying high- and low-frequency EEG oscillations contribute independently to the human BOLD signal.

Work on animals indicates that BOLD is preferentially sensitive to local field potentials, and that it correlates most strongly with gamma band neuronal synchronization. Here we investigate how the BOLD signal in humans performing a cognitive task is related to neuronal synchronization across different frequency bands. We simultaneously recorded EEG and BOLD while subjects engaged in a visual attention task known to induce sustained changes in neuronal synchronization across a wide range of frequencies. Trial-by-trial BOLD fluctuations correlated positively with trial-by-trial fluctuations in high-EEG gamma power (60. -80 Hz) and negatively with alpha and beta power. Gamma power on the one hand, and alpha and beta power on the other hand, independently contributed to explaining BOLD variance. These results indicate that the BOLD-gamma coupling observed in animals can be extrapolated to humans performing a task and that neuronal dynamics underlying high- and low-frequency synchronization contribute independently to the BOLD signal.

Subliminal salience search illustrated : EEG identity and deception detection on the fringe of awareness

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.

Beyond ERPs: oscillatory neuronal dynamics.

The event-related potential (ERP) approach has provided a wealth of fine-grained information about the time course and the neural basis of cognitive processing events. However, in the 1980s and 1990s, an increasing number of researchers began to realize that an ERP only represents a certain part of the event-related electroencephalographic (EEG) signal. This chapter focuses on another aspect of event-related EEG activity: oscillatory EEG activity. There exists a meaningful relationship between oscillatory neuronal dynamics, on the one hand, and a wide range of cognitive processes, on the other hand. Given that the analysis of oscillatory dynamics extracts information from the EEG/magnetoencephalographic (EEG/MEG) signal that is largely lost with the traditional time-locked averaging of single trials used in the ERP approach, studying the dynamic oscillatory patterns in the EEG/MEG is at least a useful addition to the traditional ERP approach.

Blowing your mind: a conceptual framework of augmented reality and virtual reality enhanced cultural visitor experiences using EEG experience measures.

Cultural tourism is regarded as a key contributor for economic growth in various destinations. While increasing awareness and interest of different cultures play a key role, technology has made information and interaction at these sites more accessible and engaging. An increasing amount of research is being conducted around the potential and implementation of AR and VR technology to enhance the visitor experience. However, limited theoretical knowledge has been developed on how these need to be designed to facilitate forming memorable experiences at cultural tourism sites. This study discusses elements affecting the visitor experience and discusses how AR and VR should be designed to contribute to enhancing the experience and making it memorable from a theoretical perspective. Further research recommendations are outlined that suggest the use of complementing research methodologies to better understand the nature of experiences in order to design AR and VR application more purpose-specifically.

Trial-by-trial coupling between EEG and BOLD identifies functional networks related to alpha and theta EEG power increases during working memory maintenance.

Combining EEG and fMRI to investigate the post-movement beta rebound.