Talk:BCI based on Motor Imagery
How to set up BCI instruments
- Electroencephalograph (with PCMCIA connector)
- Laptop (ensures that the AC adapter is NOT connected, for safety reasons)
- Electrodes or an Electrodes Cap (designed for the 10-20 system)
- Conductive gel
- Tape measure
- Adhesive tape
Before starting, be sure that the Electroencephalograph AC adapter is far away from the patient because 50Hz can interfere and destroy EEG signal. Don’t forget also to switch-off your mobile phone. Now you can choose if you want to use an electrodes cap, or separated electrodes.
Choose the suitable size for the patient, and then put the cap on his head in the correct position:
- measure his head size (from the nasion NS to the ….) this is the 100% of the measure
- now you can put the CZ electrode at 50% of the entire measure, and check the positions of the other electrodes.
- Connect the reference electrode to the forehead and the GND electrode to the right earlobe.
If you haven’t got an electrodes cap you can position them one by one following this figure, with the relatives measures of each electrode:
FIGURA 10 20 system
If you want to eliminate EOG artefacts from your data acquisitions, you would record EOG signal putting 2 more electrodes, near the patient eye. One electrode just over the eyebrow and one under the eye (REF) , like in the figure:
FIGURA elettrodi occhi