Compare and Contrast

# Consumer EEG Headsets

Your choice of headset will depend on what you intend to use it for. The answer will depend on your budget, interest, project idea and the number of electrodes required. Before purchasing a headset, think about your programming experience and Project Idea.

# What to look for in a headset.

When deciding which EEG headset to purchase, there are a few features you should look at when making your decision.

## Number and Placement of Electrodes:

Depending on the type of brain response you want to measure, your system may need a minimum number of electrodes. Measuring Relaxation levels is easy with 1 or 2 electrodes but measuring other brain activity can be difficult. In most eeg papers, they will state where on the brain the strong response came from.

Also, many consumer EEG’s have electrodes which are rigid and can’t be moved. If you want to measure Motor Imagery with the Muse, you won’t have much success. You would be better off with an OpenBCI so that you can place the electrodes where you want.

IMOTIONS EEG 101 Guide

## Sampling Rate:

The Sampling Rate of an EEG is the number of sample a second you can get from your device. Most devices will have a minimum of 256 samples a second, but you can find some which have a higher sampling rate. Depending on the frequency you are interested in studying, your sampling rate needs to be at least 2.5 times greater.

This EEG tutorials has some more details on the sampling rate

Simply put, the Analog to Digital Converter (ADC) Bits is the resolution of the signal. The number of bits is important in being able to accurately estimate the voltage, but more bits doesn’t necessarily mean better quality data. To give an idea of how it would work with eeg data, let’s say your system has 4 ADC bits and you want to measure a signal between 0 and 10 Volts. This would mean that your computer would represent the data in the following way:

 Voltage 2- Bit Digital Representation 0-2.5 00 2.5-5.0 01 5.0-7.5 10 7.5-10.0 11

# Devices

## Muse

Muse is an EEG device which has developed as a meditation device. It has 4 channels, 1 reference and two ground electrodes. The Muse headband comes with electrodes placed on Af7 and Af8 location if you are following 10-20 International Standards. It is one of the easier bands to get started with if you are interested in learning EEG as it requires no head prep.

#### Features:

• 4 electrodes
• Static Electrode Placement (Af7 and Af8)
• Dry Electrodes
• 256 Hz Sampling Rate
• 12 bits
• Research Tools for Windows, Mac and Linux
• SDK for Android, IOS, Windows

#### Known Recordable EEG Paradigms:

• “Relaxation” Level
• “Concentration” levels
• Frontal Asymmetry
• P300

## Emotiv Epoc

The Emotiv Epoc is one of the first consumer EEG devices released on the market. The popularity of the company surged in 2012 and 2013, which can be reflected by its sales and number of DIY projects.

The Epoc is more stylish and easier to wear. It has 14 channel EEG which has a static form factor. This board is a good option for easy development and it only requires software experience. It is a popular device to use for EEG research as the cost is much better versus other research grade mobile EEG providers. It is however less economic than other commercial headsets and has an additional cost for accessing the data that the headset collects.

#### Features

• 14 channels
• Rigid Electrode Placement (AF3, F7, F3, FC5, T7, P7, O1, O2, P8, T8, FC6, F4, F8, AF4)
• Wet Electrodes (require saline water)
• 2048 Hz Sampling Rate
• 14 bits

#### Known Recordable EEG Paradigms:

Many paradigms which need only 14 channels or less

## Neurosky Mindwave

The Neurosky is one of the original consumer EEGs on the market. The design is simple and only has 1 channel meant for use. Some people say they have built more complicated products with them.

#### Features

• 1 channel
• Rigid Electrode Placement (AFz)
• Dry Electrodes
• 512 Hz Sampling Rate
• 12 bits
• Available SDK

#### Known Recordable EEG Paradigms:

• “Relaxation” Level
• “Concentration” levels

US Price (as of January 2017): : $100 ## Features Comparison DeviceChannelsADC BitsSample RateMotion sensorsLSL SupportSD Card SupportTTLBattery LengthCost (US) as of Jan 2017 Muse 20164-612256 Hz3 axisYesNoMaybe5 hours$200
Epoc14+2 ref16256 Hz9 axisPossibleWith accessoryN/A6 hours using BTLE$799 Insight5+2 ref152048 Hz9 axisPossibleWith accessoryN/A4 hours using Bluetooth$300
OpenBCIup to 16 channels24250 Hz3 axisYesYesYes~26 hours$500 for 8 channels,$949 for 16
Neurosky Mindwave1+1 ref12512HzN/AN/AN/AN/A8 hours\$99.99