BIOPAC® Systems, Inc. Logo

Maximum number of channels for EEG

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.
Unipolar recording:
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.
Bipolar recording:
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:
2 electrodes: 1 amplifier
3 electrodes: 3 amplifiers
4 electrodes: 6 amplifiers
5 electrodes: 10 amplifiers
6 electrodes: 15 amplifiers
Page last modified 30Dec2014

Associated Applications

Spotlight On
Remote Screen-based Eye Tracking BAr

Remote Screen-based Eye Tracking Bars

This mini screen-based remote eye tracking bar provides gaze position, dwell time, blink rate, pupil size, and more. Use with an AcqKnowledge Eye Tracking Integration License (ACK100W-EYE) to access valuable eye tracking metrics: Gaze Path, Gaze Plot, Heat Map, and Attention Map. Create user-defined Areas of Interest (AOI) and select Scarf Plot, String Plot, Pie Chart, […]

View All
Latest News

New Citations | Using Wireless Technology to Support Psych Research

Solving Physical Stress Issues for Surgeons Physical stress in the operating room is common for surgeons, considering how much time they spend in an upright standing position during surgical procedures. With procedures that require standing for several hours and average reported working times of 60-80 hours a week, surgeons seem to be at risk for musculoskeletal […]

New Eye Tracking Glasses Bring Real-world Data to Academic Research

BIOPAC combines eye tracking with mobile data logging and physiology data collection to run experiments in the lab or in the real world BIOPAC Systems, Inc. is pleased to announce new eye tracking integration for researchers who conduct experiments from mobile participants in diverse locations. ETVision (EYE-ETV) eye tracking glasses now integrate with BIOPAC wireless systems and software, […]

Read All
Request a Demonstration
Request a Demonstration