scholarly journals Online Detection of P300 and Error Potentials in a BCI Speller

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Bernardo Dal Seno ◽  
Matteo Matteucci ◽  
Luca Mainardi

Error potentials (ErrPs), that is, alterations of the EEG traces related to the subject perception of erroneous responses, have been suggested to be an elegant way to recognize misinterpreted commands in brain-computer interface (BCI) systems. We implemented a P300-based BCI speller that uses a genetic algorithm (GA) to detect P300s, and added an automatic error-correction system (ECS) based on the single-sweep detection of ErrPs. The developed system was tested on-line on three subjects and here we report preliminary results. In two out of three subjects, the GA provided a good performance in detecting P300 (90% and 60% accuracy with 5 repetitions), and it was possible to detect ErrP with an accuracy (roughly 60%) well above the chance level. In our knowledge, this is the first time that ErrP detection is performed on-line in a P300-based BCI. Preliminary results are encouraging, but further refinements are needed to improve performances.

2007 ◽  
Vol 2007 ◽  
pp. 1-8 ◽  
Author(s):  
Robert Leeb ◽  
Doron Friedman ◽  
Gernot R. Müller-Putz ◽  
Reinhold Scherer ◽  
Mel Slater ◽  
...  

The aim of the present study was to demonstrate for the first time that brain waves can be used by a tetraplegic to control movements of his wheelchair in virtual reality (VR). In this case study, the spinal cord injured (SCI) subject was able to generate bursts of beta oscillations in the electroencephalogram (EEG) by imagination of movements of his paralyzed feet. These beta oscillations were used for a self-paced (asynchronous) brain-computer interface (BCI) control based on a single bipolar EEG recording. The subject was placed inside a virtual street populated with avatars. The task was to “go” from avatar to avatar towards the end of the street, but to stop at each avatar and talk to them. In average, the participant was able to successfully perform this asynchronous experiment with a performance of 90%, single runs up to 100%.


2020 ◽  
Vol 16 (2) ◽  
Author(s):  
Stanisław Karkosz ◽  
Marcin Jukiewicz

AbstractObjectivesOptimization of Brain-Computer Interface by detecting the minimal number of morphological features of signal that maximize accuracy.MethodsSystem of signal processing and morphological features extractor was designed, then the genetic algorithm was used to select such characteristics that maximize the accuracy of the signal’s frequency recognition in offline Brain-Computer Interface (BCI).ResultsThe designed system provides higher accuracy results than a previously developed system that uses the same preprocessing methods, however, different results were achieved for various subjects.ConclusionsIt is possible to enhance the previously developed BCI by combining it with morphological features extraction, however, it’s performance is dependent on subject variability.


Author(s):  
Guilherme Antonio Camelo ◽  
Maria Luiza Menezes ◽  
Anita Pinheiro Sant’Anna ◽  
Rosa Maria Vicari ◽  
Carlos Eduardo Pereira

2020 ◽  
Vol 17 (4) ◽  
pp. 1616-1621
Author(s):  
K. Sathish ◽  
Aritra Paul ◽  
Debapriya Roy ◽  
Ishmeet Kalra ◽  
Simran Bajaj

The concept is designed to improve upon the recent developed system, utilizing auditory steady state response (ASSR) as a basis for the Brain Computer Interface (BCI) paradigm. It utilizes the classification of signals through a discrete wavelet transform (DWT) before the actual transmission to reduce overhead at the processing system. The electroencephalogram (EEG) obtained from the subject is through a p300 based EEG receivers. A compression algorithm is used to reduce the bandwidth usage and provide a quicker transmission of the large and continuous EEG. An Arduino board along with a proximity sensor is used to detect the presence and distance of the subject and consequently control playback of a single frequency audio signal, which as received by the user, is used for producing the EEG signals. A continuous focus of the user is required on the playback of the single frequency sound to produce a sizeable reading. At the receiving end, another Arduino board is installed with an SD card module, which contains the commands, responsible for the actual control of the devices. The concept can be utilized for various purposes from controlling IoT based systems to wheelchairs and hospital beds as well as bionic limbs, which however are limited due to the overall bulk of all the equipment currently required. The main aim of this paper is to propose an improvement in the transmission, reduction the latency of the signals and to provide a concept for utilization by the handicapped or physically impaired patients. Since the EEG is obtained through the inner ear of the subject, it completely eliminates any need for invasive surgery and provides a simplified solution. Developments have shown to be able to achieve over 95% of accuracy in the domain, currently limited by length of the EEG required in order to process the actual commands from the subject’s brain.


2008 ◽  
Vol 2008 ◽  
pp. 1-5 ◽  
Author(s):  
Tao Geng ◽  
John Q. Gan ◽  
Matthew Dyson ◽  
Chun SL Tsui ◽  
Francisco Sepulveda

A novel 4-class single-trial brain computer interface (BCI) based on two (rather than four or more) binary linear discriminant analysis (LDA) classifiers is proposed, which is called a “parallel BCI.” Unlike other BCIs where mental tasks are executed and classified in a serial way one after another, the parallel BCI uses properly designed parallel mental tasks that are executed on both sides of the subject body simultaneously, which is the main novelty of the BCI paradigm used in our experiments. Each of the two binary classifiers only classifies the mental tasks executed on one side of the subject body, and the results of the two binary classifiers are combined to give the result of the 4-class BCI. Data was recorded in experiments with both real movement and motor imagery in 3 able-bodied subjects. Artifacts were not detected or removed. Offline analysis has shown that, in some subjects, the parallel BCI can generate a higher accuracy than a conventional 4-class BCI, although both of them have used the same feature selection and classification algorithms.


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