If you are using a single MP100/MP150 system, the maximum number of EEG amplifiers you can have is 16. If more channels are required, it is possible to link acquisitions from more than one MP150. However, the modular design of MP150 systems does not lend itself well to high density EEG recording, so BIOPAC does not strongly recommend this solution.
The Mobita System 32-channel wireless EEG system is a better solution for multi-channel applications.
For unipolar recording you need as many amplifiers as you have sites to record from. For example, for 16 sites you would need 16 EEG amplifiers. To perform this recording you would need 16 active electrodes, 1 reference (linked via 15 jumper cables to connect all amplifiers), and 1 ground.
For bipolar recording the number of EEG amplifiers will be the same as the number of pairs of electrode sites for which you want to calculate the potential difference. Therefore, if you want to look at all possible pairs, you can calculate the combinations without repetition: n!/(r!(n-r)!) where n is the number of electrode sites and r is 2. For example, for a bipolar recording on 5 sites you would need 5!/(2!3!) = 10 EEG amplifiers. This assumes that you want to look at the potential difference between all possible combinations of electrode sites. This is the maximum number of EEG amplifiers that would be required.
Here is a reference for the number of EEG amplifiers required if you need to look at all electrode pair potential differences:
Simple, portable, accurate, wireless This complete system provides acquisition and analysis of high fidelity wireless EEG plus ECG with the B-Alert X10 headset and sensor strips (1 small, 1 medium), plus AcqKnowledge software with powerful analysis tools, including automated scoring and reporting options, and B-Alert Cognitive State analysis software. The B-Alert X10 mobile-wireless EEG system delivers real-time measurements for a […]
BIOPAC provides software and hardware that allow for research teams to record and analyze respiration activity in physiological experimentation. Here are a few notable studies in monitoring respiration and cardiovascular activity. The coupling between peripheral microcirculation and slow breathing: The purpose of this study was to investigate the coupling of breathing movements and microcirculatory blood […]
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