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Comparisons of BCI Headsets/Headbands

In this post, I have listed the comparisons of following brain computer interfaces based on the references mentioned at the bottom of the page. Headset Brand Support P300/SSVEP Additional SW/HW Licensing Price OpenBCI Good Cyton BioSensing Board None $1420 for 16 channels $920 for 8 channels Emotive EPOC + Good Emotiv SDK Raw EEG data needs licensing for online analysis $700 for 14 electrodes $300 for 5 electrodes $55-$99 per month for online analysis Neurosky Mindwave Mobile 2 Less efficient Freely Downloadable Software None $100 for headset with free software OpenEEG Good Requires Electronic Montage None Varies based on electronic montage Muse Supported Freely Downloadable Software None Around $250 for Muse2 OpenBCI OpenBCI is using the quite advance...
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BCI Related Facts And Questions

Facts: 1. Faster P300 responses are indicative of better cognitive performance in attentional and immediate memory task [Abiri_Borhani_Sellers_Jiang_Zhao]. Example: Keyboard 2. In addition, the SSVEP frequencies can be more reliably classified than event-related potentials  [Abiri_Borhani_Sellers_Jiang_Zhao]. 3. SSVEP depicts a stable characteristic of the spectral content of EEG signals. Among various EEG paradigms, SSVEP is less vulnerable to artifacts and has higher Information Transfer Rate ITR.  [Abiri_Borhani_Sellers_Jiang_Zhao] 4. Power line interference can also be removed by applying a notch filter at 50 or 60 Hz, and sometimes this kind of notch filter is pre-built in some headsets. [EEG Signal Processing and Feature Extraction, Page 75] 5. Collectively, a “typical” sample in a “typical” ERP study usually consists of university students, age between 18 and 30, right-handed, having normal IQ, reading ability, and motor skills. [EEG Signal Pro...
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BCI Vocabulary Reference

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synapse : In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell. In many synapses, the presynaptic part is located on an axon and the postsynaptic part is located on a dendrite or soma. Dipole : There are many dipoles in the brain. Each dipole will influence the charge in almost all directions. The voltage fluctuation measured at the electrode on the scalp is the sum of  activities generated from many neural sources.  [EEG Signal Processing and Feature Extraction, Page 25] Dendrites and an Axon : Apart from the cell body, a typical neuron possesses several dendrites and an axon. The dendrites, extruding from the cell body, are primarily responsible for providing a large receptive area for synaptic input, thus receiving the electrical input to the cell body. The single axon, which arises from the cell body, mainly takes charge of the transm...
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Brainstorming - Visual Evoked Potential Based PID Controller

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This is an attempt to brainstorm the use of Visual Evoked Potentials (VEP)  in the brain to control a system. Here in this case, I am assuming the system to be a Wall Follower. I am planning to use a toy car which follows the wall to be controlled by PID controller algorithm. The VEP waveform looks like below. As we can see, it has positive peak and negative peak. If there is some way to measure the amplitude of these peaks and convert them into power (positive or negative), we can feed that power back into the toy car and the toy car should follow the wall. Below is a little algorithm which shows the use of PID controller using VEP. while(true) {     Variable Power = getVEPBasedPower();     Error =  Variable Power - getSSVEPBasedPower();     Integral = Error + Integral;     Derivative = Error - LastError;     Correction = Kp * Error + Kd * Derivative + Ki * Integral;     PowerToLeftMotor = R...
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