Event-Related Potentials: Cognition in Brain-Computer Interfaces


May 14, 2017


Organizer: João Luís Garcia Rosa

Department of Computer Science

Institute of Mathematics and Computer Sciences, University of São Paulo at São Carlos, Brazil



Abstract:  In many scientific fields, a very useful way to learn about a system is to study its reaction to disturbances. In brain research, it is also a common strategy in order to see how individual neurons or large populations of neurons, as measured by electroencephalography (EEG), react to different types of stimuli. Event-related potential (ERP) is an electrical potential generated by the brain that is related to an event (usually a stimulus or a response). ERPs were originally called evoked potentials (EPs) because they were electrical potentials that were evoked by stimuli (as opposed to the spontaneous EEG rhythms). ERPs can be very useful in elucidating cognitive mechanisms and their neural substrates. Cognition depends on the functioning of the cerebral cortex. Therefore, understanding the neural basis of cognition will likely require knowledge of cortical operations at all organizational levels. The cooperative activity of the network influence the effects that are relevant for cognition. ERP components are typically identified according to their polarity (positive or negative) and their time latency following stimulus onset. ERPs can provide information about the spatial distribution of large-scale network activity underlying a cognitive function. An important ERP example is the P3 (or P300) signal observed in EEG recordings, so called because it is the third positive deflection in the EEG signal, which occurs approximately 300 ms after the stimulus. P3 is evoked by the occurrence of an unusual or unexpected stimulus. Many researchers use the P3 to study cognitive processes, such as signal comparison, recognition, decision-making, attention, and memory upgrade. Brain-computer interfaces (BCI) researchers often use ERP-based P300 spellers as an alternative channel of communication for people with severe neuro-muscular diseases. Abnormal P3 responses may reflect conditions in which cognition is impaired, as has been shown in depression, schizophrenia, dementia, and others.

Keywords: Event-related potential (ERP), Brain-Computer Interfaces (BCI), cognition, Computational Neuroscience.



Outline of the tutorial: BCI: Communication without muscles; EEG: A non-invasive procedure, Recordings, Artifacts; Stimulus-evoked activity: Response to stimuli, ERP, Analysis, ERP and cognition; Applications: P300 speller, Lie detection.

Tutorial Topic: Computational Neuroscience

Rationale: A non-invasive tool to understand brain reactions to stimuli in order to build useful computational models, like brain-computer interfaces.

Relevance for IJCNN: Brain-Computer Interfaces, brain models, and biologically inspired neural networks are subjects of interest to IJCNN audience

Presentation Slides: [To be included]



Bio of the organizer: João Luís G. Rosa is an associate professor at the Department of Computer Science in the Institute of Mathematics and Computer Sciences (ICMC) - University of São Paulo (USP), in São Carlos, Brazil. He is with the Bio-inspired Computing Laboratory (BioCom). His research interests include brain-computer interfaces, computational neurodynamics, and biologically plausible neural networks. Regarding his academic experience, he has taught graduate level courses on computer science, disciplines Brain-Computer Interfaces, Artificial Neural Networks, and Theory of Computation, and undergraduate level courses for computer engineering and computer science, disciplines Programming Languages, Artificial Intelligence, Algorithms, and Theory of Computation and Formal Languages, at University of São Paulo at São Carlos, São Paulo, Brazil. He has been interested on neural networks since 1990, and since 1998, he has contributed to the field of Biologically Plausible Artificial Neural Networks with published papers and supervision of undergraduate and graduate students. Since 2009, he has been a reviewer for the ACM Computing Reviews. He is also reviewer for several periodicals and conferences. He published two books (on Artificial Intelligence Fundamentals and on Formal Languages and Automata, both in Portuguese), two book chapters (the last one, in 2013, on Biologically Plausible Artificial Neural Networks), and papers in journals and conference proceedings. He edited one book on Artificial Neural Networks – Models and Applications in 2016. He presented an IJCNN 2005 Tutorial on “Biologically Plausible Artificial Neural Networks” in Montreal, Canada, and an IJCNN 2015 Tutorial on “Noninvasive Electroencephalogram-based Brain-Computer Interfaces” in Killarney, Ireland. He has been an IEEE senior member since 2015.



Disclaimer: The opinions expressed in this web page and the presentation slides are that of the organizer, not of the IJCNN conference or IEEE, or INNS, or any other entity.

Last update: March 2, 2017.