An Improved Stimuli System for Brain-Computer Interface Applications

2013 ◽  
Vol 1 (4) ◽  
pp. 1-8 ◽  
Author(s):  
Irina-Emilia Nicolae
Keyword(s):  
Reaction Time ◽  
Motor Cortex ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Auditory Stimuli ◽  
Synchronous Systems ◽  
Spectral Perturbation

When developing a motion synchronous Brain-Computer Interface, it is very important to have effective stimuli. This research tests and proposes an improved brain computer interface stimulus system, based on event related spectral perturbation. In order to investigate the reaction of the motor cortex to stimuli, the influence of the human senses has to be investigated. Considering the limitations of human senses, the article proposes effective visual and auditory stimuli in two similar tasks, to gain accuracy and better reaction time (RT) for real movements in Brain-Computer Interface synchronous systems.

Research of “Yes” and “No” Responses by Auditory Stimuli in Human EEG

2013 ◽  
Vol 310 ◽  
pp. 660-664 ◽  
Author(s):  
Zi Guang Li ◽  
Guo Zhong Liu
Keyword(s):  
Communication Channel ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Auditory Stimuli ◽  
Support Vector ◽  
Quality Life ◽  
Asking Questions ◽  
Command Signals ◽  
Different Characteristics ◽  
The Brain

As an emerging technology, brain-computer interface (BCI) bring us a novel communication channel which translate brain activities into command signals for devices like computer, prosthesis, robots, and so forth. The aim of the brain-computer interface research is to improve the quality life of patients who are suffering from server neuromuscular disease. This paper focus on analyzing the different characteristics of the brainwaves when a subject responses “yes” or “no” to auditory stimulation questions. The experiment using auditory stimuli of form of asking questions is adopted. The extraction of the feature adopted the method of common spatial patterns(CSP) and the classification used support vector machine (SVM) . The classification accuracy of "yes" and "no" answers achieves 80.2%. The experiment result shows the feasibility and effectiveness of this solution and provides a basis for advanced research .

scholarly journals 2190 Longitudinal changes in EEG power envelope connectivity are proportional to motor recovery in chronic stroke patients

2018 ◽  
Vol 2 (S1) ◽  
pp. 17-17
Author(s):  
Joseph B. Humphries ◽  
David T. Bundy ◽  
Eric C. Leuthardt ◽  
Thy N. Huskey
Keyword(s):  
Motor Cortex ◽  
Motor Imagery ◽  
Stroke Rehabilitation ◽  
Brain Computer Interface ◽  
Chronic Stroke ◽  
Motor Recovery ◽  
Stroke Recovery ◽  
Computer Interface ◽  
Beta Band ◽  
Stroke Patients

OBJECTIVES/SPECIFIC AIMS: The objective of this study is to determine the degree to which the use of a contralesionally-controlled brain-computer interface for stroke rehabilitation drives change in interhemispheric motor cortical activity. METHODS/STUDY POPULATION: Ten chronic stroke patients were trained in the use of a brain-computer interface device for stroke recovery. Patients perform motor imagery to control the opening and closing of a motorized hand orthosis. This device was sent home with patients for 12 weeks, and patients were asked to use the device 1 hour per day, 5 days per week. The Action Research Arm Test (ARAT) was performed at 2-week intervals to assess motor function improvement. Before the active motor imagery task, patients were asked to quietly rest for 90 seconds before the task to calibrate recording equipment. EEG signals were acquired from 2 electrodes—one each centered over left and right primary motor cortex. Signals were preprocessed with a 60 Hz notch filter for environmental noise and referenced to the common average. Power envelopes for 1 Hz frequency bands (1–30 Hz) were calculated through Gabor wavelet convolution. Correlations between electrodes were then calculated for each frequency envelope on the first and last 5 runs, thus generating one correlation value per subject, per run. The chosen runs approximately correspond to the first and last week of device usage. These correlations were Fisher Z-transformed for comparison. The first and last 5 run correlations were averaged separately to estimate baseline and final correlation values. A difference was then calculated between these averages to determine correlation change for each frequency. The relationship between beta-band correlation changes (13–30 Hz) and the change in ARAT score was determined by calculating a Pearson correlation. RESULTS/ANTICIPATED RESULTS: Beta-band inter-electrode correlations tended to decrease more in patients achieving greater motor recovery (Pearson’s r=−0.68, p=0.031). A similar but less dramatic effect was observed with alpha-band (8–12 Hz) correlation changes (Pearson’s r=−0.42, p=0.22). DISCUSSION/SIGNIFICANCE OF IMPACT: The negative correlation between inter-electrode power envelope correlations in the beta frequency band and motor recovery indicates that activity in the motor cortex on each hemisphere may become more independent during recovery. The role of the unaffected hemisphere in stroke recovery is currently under debate; there is conflicting evidence regarding whether it supports or inhibits the lesioned hemisphere. These findings may support the notion of interhemispheric inhibition, as we observe less in common between activity in the 2 hemispheres in patients successfully achieving recovery. Future neuroimaging studies with greater spatial resolution than available with EEG will shed further light on changes in interhemispheric communication that occur during stroke rehabilitation.

scholarly journals Increased motor cortex excitability during motor imagery in brain-computer interface trained subjects

2013 ◽  
Vol 7 ◽  
Author(s):  
Olesya A. Mokienko ◽  
Alexander V. Chervyakov ◽  
Sofia N. Kulikova ◽  
Pavel D. Bobrov ◽  
Liudmila A. Chernikova ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Motor Imagery ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Trained Subjects ◽  
Motor Cortex Excitability

scholarly journals Primary motor cortex has independent representations for ipsilateral and contralateral arm movements but correlated representations for grasping

2019 ◽  
Author(s):  
John E Downey ◽  
Kristin M Quick ◽  
Nathaniel Schwed ◽  
Jeffrey M Weiss ◽  
George F Wittenberg ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Primary Motor Cortex ◽  
Human Subjects ◽  
Brain Computer Interface ◽  
Hand Movement ◽  
Arm Movement ◽  
Computer Interface ◽  
Contralateral Movement ◽  
Contralateral Motor ◽  
Continuous Movements

AbstractMotor commands for the arms and hands generally originate in contralateral motor cortex anatomically. However, ipsilateral primary motor cortex shows activity related to arm movement despite the lack of direct connections. The extent to which the activity related to ipsilateral movement is independent from that related to contralateral movement is unclear based on conflicting conclusions in prior work. Here we present the results of bilateral arm and hand movement tasks completed by two human subjects with intracortical microelectrode arrays implanted in left primary motor cortex for a clinical brain-computer interface study. Neural activity was recorded while they attempted to perform arm and hand movements in a virtual environment. This enabled us to quantify the strength and independence of motor cortical activity related to continuous movements of each arm. We also investigated the subjects’ ability to control both arms through a brain-computer interface system. Through a number of experiments, we found that ipsilateral arm movement was represented independently of, but more weakly than, contralateral arm movement. However, the representation of grasping was correlated between the two hands. This difference between hand and arm representation was unexpected, and poses new questions about the different ways primary motor cortex controls hands and arms.

Pleasure detection from the facial motor cortex by the brain-computer interface

2009 ◽  
Author(s):  
Zia Mohy Ud-Din ◽  
Sang Hyo Woo ◽  
Wei Qun ◽  
Jee Hyun Kim ◽  
Hwan Soo Jang ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
The Brain

The Effect of Auditory Stimuli on User’s Meditation and Workload in a Brain–Computer Interface Game

2019 ◽  
Vol 31 (3) ◽  
pp. 250-262 ◽  
Author(s):  
Gabriel Alves Mendes Vasiljevic ◽  
Leonardo Cunha de Miranda
Keyword(s):  
Brain Computer Interface ◽  
Controlled Experiment ◽  
The Self ◽  
Computer Interface ◽  
Auditory Stimuli ◽  
Subjective Workload ◽  
Brain Signals ◽  
Key Features ◽  
External Stimuli ◽  
Over Time

Abstract The advancement of Brain–computer interface (BCI) technology allowed for the development of applications not only for physically-impaired users, but for entertainment purposes as well. However, there are still numerous challenges in the development of such applications, as it is not known to which extent external stimuli may interfere with the captured brain signals. Being so, understanding the possible limitations caused by these external stimuli may help developers and designers in the development of future BCI-based applications. This paper presents the results of a controlled experiment designed for investigating the effects of auditory stimuli (AS) on subjects playing a neurofeedback-based game. The experiment consisted of sixteen volunteer subjects who played a total of twelve game matches each, for a total of 144 matches, over the course of three experiment sessions. Statistical analysis and qualitative instruments were employed to investigate key features of the subjects’ interaction with the game over time, especially regarding the influence of AS in both subjects’ performance and self-assessed, subjective workload. It was concluded that the subjects’ level of meditation tends to increase over time, that the self-assessed workload tends to decrease over time, and that the game’s AS did neither significantly influenced the performance nor the subjective workload of the subjects. Research Highlights The influence of auditory stimuli (AS) was investigated with a brain–computer interface game. Meditation level and workload were assessed and evaluated in a controlled experiment setup. Subjects’ performance tends to increase over time, while self-assessed workload tends to decrease. The presence of AS did not influenced the subjects’ meditation level and workload.

scholarly journals Microscale recording from human motor cortex: implications for minimally invasive electrocorticographic brain-computer interfaces

2009 ◽  
Vol 27 (1) ◽  
pp. E10 ◽  
Author(s):  
Eric C. Leuthardt ◽  
Zac Freudenberg ◽  
David Bundy ◽  
Jarod Roland
Keyword(s):  
Motor Cortex ◽  
Minimally Invasive ◽  
Primary Motor Cortex ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Future Application ◽  
Electrode Spacing ◽  
Sufficient Information ◽  
Invasive Monitoring ◽  
Seizure Localization

Object There is a growing interest in the use of recording from the surface of the brain, known as electrocorticography (ECoG), as a practical signal platform for brain-computer interface application. The signal has a combination of high signal quality and long-term stability that may be the ideal intermediate modality for future application. The research paradigm for studying ECoG signals uses patients requiring invasive monitoring for seizure localization. The implanted arrays span cortex areas on the order of centimeters. Currently, it is unknown what level of motor information can be discerned from small regions of human cortex with microscale ECoG recording. Methods In this study, a patient requiring invasive monitoring for seizure localization underwent concurrent implantation with a 16-microwire array (1-mm electrode spacing) placed over primary motor cortex. Microscale activity was recorded while the patient performed simple contra- and ipsilateral wrist movements that were monitored in parallel with electromyography. Using various statistical methods, linear and nonlinear relationships between these microcortical changes and recorded electromyography activity were defined. Results Small regions of primary motor cortex (< 5 mm) carry sufficient information to separate multiple aspects of motor movements (that is, wrist flexion/extension and ipsilateral/contralateral movements). Conclusions These findings support the conclusion that small regions of cortex investigated by ECoG recording may provide sufficient information about motor intentions to support brain-computer interface operations in the future. Given the small scale of the cortical region required, the requisite implanted array would be minimally invasive in terms of surgical placement of the electrode array.

Appropriate auditory stimuli for P300 brain–computer interface

2010 ◽  
Vol 68 ◽  
pp. e327
Author(s):  
Hideki Nojo ◽  
Minoru Kawasaki ◽  
Tetsu Jyo ◽  
Atsushi Ishiyama ◽  
Naoko Kasai ◽  
...  
Keyword(s):  
Brain Computer Interface ◽  
Computer Interface ◽  
Auditory Stimuli
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