Highly Interactive BCI based on Flicker-Free SSVEP

Visual evoked potential-based brain–computer interfaces (BCIs) have been widely investigated because of their easy system configuration and high information transfer rate (ITR). However, the uncomfortable flicker or brightness modulation of existing methods restricts the practical interactivity of BCI applications. In our study, a flicker-free steady-state motion visual evoked potential (FF-SSMVEP)-based BCI was proposed. Ring-shaped motion checkerboard patterns with oscillating expansion and contraction motions were presented by a high-refresh-rate display for visual stimuli, and the brightness of the stimuli was kept constant. 

Compared with SSVEPs, few harmonic responses were elicited by FF-SSMVEPs, and the frequency energy of SSMVEPs was concentrative. These FF-SSMVEPs evoked “single fundamental peak” responses after signal processing without harmonic and subharmonic peaks. More stimulation frequencies could thus be selected to elicit more responding fundamental peaks without overlap with harmonic peaks. A 40-target online SSMVEP-based BCI system was achieved that provided an ITR up to 1.52 bits per second (91.2 bits/min), and user training was not required to use this system. This study also demonstrated that the FF-SSMVEP-based BCI system has low contrast and low visual fatigue, offering a better alternative to conventional SSVEP-based BCIs.

For more information about BCI/EEG press here.

BioSemi activeTwo EEG using SSVEP

The BCI and Neural Engineering Lab of University of Essex shows in the next video how to control a cursor using SSVEP.

For more information about BCI/EEG press here.

BCI by Electrical Cortex Activity: Challenges in Creating a Cognitive System for Mobile Devices Using SSVEP

Conference: DoCEIS2016 - Technological Innovation for Cyber-Physical Systems, Portugal
Book Title: Technological Innovation for Cyber-Physical Systems
DOI: 10.1007/978-3-319-31165-4_14

Abstract: The research field of Brain-Computer Interfaces (BCI) emerged in an attempt to enable communication between paralyzed patients and technology. Identifying an individual’s mental state, through his brain’s electric activity, a typical BCI system assigns to it a particular action in the computer. It is known that when the visual cortex is stimulated with a certain frequency, it shows activity with the same frequency. This Steady-State Visually Evoked Potential (SSVEP) activity can be used to achieve the aforementioned communication goal. In this work, we first analyze the spontaneous electrical activity of the brain, to distinguish two mental sates (concentration / meditation). Then, following an SSVEP type of approach, we divide the stimulating screen in four areas, each of which flickering at a distinct frequency. By observing the responding frequency from the occipital lobe of the subject, we can then estimate the 2 bit decision he made. We observe that such a setup is efficient for real time BCI, and can be easily integrated in mobile devices. Besides, the user is able to change voluntarily her/his decisions, interacting with the system in a natural manner.

For more information click here.

Software for Visual Psychophysics

Prof. Hans Strasburger from Universität München brings together to this page the various existing tools to work with Psychophysics, divided by 15 topics:

• Libraries, Public Domain and Commercial Applications for Psychophysics;
• Psychophysical data analysis, SDT;
• Ophthalmology/Optometry/Neuroophthalmology;
• Psychological Experimenting Systems;
• Cognitive Neuroscience;
• (...)

How well do we see? How can visual function be described and which mechanisms can be thought to underly? Visual psychophysics tries to give answers to these general questions, and research in this area needs specialised software. This is an overview on what is available.

PsychToolbox, for Matlab or Octave, is one of tools example commonly used in SSVEP.

Play computer games without using your hands or feet

New BCI solutions are increasingly common in laboratories and research institutes. One such example is the project developed by Christoph Hintermüller and his team from g.tec Guger Technologies. He says: “We have developed so called brain-computer interfaces which allow the user to control different devices and programmes without hands, by means of the user’s thoughts.”

This is one more approach to play a computer game hands-free. Using SSVEP the user selects the commands by simply looking at the blinking arrows on the screen. The frequency of the flashing is reproduced in the brain cortex and read by the electrodes at occipital area.

Also Arnau Manzanal of the research and development department says: "As soon as we have understood the electroencephalography patterns produced by the groups of neurons in the brain, we can map the brain activity to any commands for any device, like a television or a motorised system for the home".

More information about this article can be found here.

3rd International Winter BCI Conference - 49 Publications

All the links to the 49 publications from the 3rd International BCI Conference, presented in this blog some weeks ago, are available here or at IEEE Xplore Digital Library.

• Tutorial on multimodal neuroimaging for brain-computer interfacing
• Bayesian common spatial patterns
• Brain-computer interface for stroke rehabilitation with clinical studies
• Mobile real-time EEG imaging Bayesian inference with sparse, temporally smooth source priors
• Neuro-driving: Automatic perception technique for upcoming emergency situations
• Spatial projections of neural arrays: A short guide to classic and new signal analysis techniques
• Divergence estimation for machine learning and signal processing
• Progress toward a high-performance neural prosthetic
• Decoding cognitive brain states
• Eeg/sonication-based brain-brain interfacing
• Japanese SRPBS for BMI research: Decoded neurofeedback as a causal tool in systems neuroscience
• A Bayesian approach for spatio-spectral filter optimization in BCI
• A novel P300-based BCI system for words typing
• Non-homogeneous spatial filter optimization for EEG-based brain-computer interfaces
• A novel tactile stimulation system for BCI feedback
• A study on information transfer rate by brain-computer interface (BCI) using functional near-infrared spectroscopy (fNIRS)
• BMFLC with neural network and DE for better event classification
• Classifying ECoG signals prior to voluntary movement onset
• Common spatial patterns based on generalized norms
• Decoding three-dimensional arm movements for brain-machine interface
• Design of a robotic wheelchair with a motor imagery based brain-computer interface
• Detection of multi-class emergency situations during simulated driving from ERP
• Dry electrode design and performance evaluation for EEG based BCI systems
• EEG asymmetry and anxiety
• Eeg-based emotion recogntion during emotionally evocative films
• Eeg-based person authentication using face stimuli
• Effects of rest frames on cybersickness and oscillatory brain activity
• Efficient edge detection method for anatomic feature extraction of neuro-sensory tissue image based on optical coherence tomography
• Emotion classification in movie clips based on 3D fuzzy GIST and EEG signal analysis
• Estimation on the development of cerebral edema from computed tomography preliminary studies for pediatric traumatic brain injury patients
• Ethical and social issues behind brain-computer interface
• Evaluation of feature extraction methods for motor imagery-based bcis in terms of robustness to slight changes of electrode locations
• “Eyes-closed” SSVEP-based BCI for binary communication of individuals with impaired oculomotor function
• Implementation of a mental spelling system based on steady-state visual evoked potential (SSVEP)
• Learning Markov random field image prior for pixelation removal of fiber microscopy using sparse coding based on Bayesian framework
• Modified pattern-reversal visual checkerboard stimuli with dual alternating frequencies for multi-class ssvep-based brain-computer interfaces
• Motor trajectory decoding based on fMRI-based BCI — A simulation study
• Multimodal imaging technique for rapid response brain-computer interface feedback
• Optimal channel selection based on statistical analysis in high dimensional NIRS data
• P300 speller using a new stimulus presentation paradigm
• Power consumption of wireless EEG device for BCI application: Portable EEG system for BCI
• The beginning of neurohaptics: Controlling cognitive interaction via brain haptic interface
• The effectiveness of epidural ECoG on brain computer interface in primate
• Three-dimensional upper limb movement decoding from EEG signals