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:
New series of unshielded 45 cm electrode leads with thin cable; suitable for facial EMG and other areas where lighter, shorter lead cables are required. Use for female Touchproof connectors to pinch clip connectors—connect electrodes to either a C-series amplifier or an MEC. The pinch connectors are light weight and the lead cable tinsel wire […]
The new issue of Psychophysiology has a study “Quantifying rapid changes in cardiovascular state with a moving ensemble average” using MEAP for preprocessing/analysis and BIOPAC hardware and software for data collection, display, and storage. The proof of concept study demonstrates a viable method for the adoption of ICG measures across the field of psychophysiology. MEAP (moving ensemble […]
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 covering MRI, ECG, and Laser Doppler Flow measurement. fMRI & Thermal Perception: The neural mechanisms underlying thermal perception (how hot or cold we perceive the temperature to be) have not been fully […]