Enobio
Wireless brain monitoring

Is ENOBIO a Dry Electrode system?
Yes, ENOBIO can be used in dry mode. We provide dry front-end electrodes for the forehead and for the scalp which can be also mixed with gel front-end electrodes. The passive DRL electrode needs gel to increase CMMR and improve immunity to artifacts.

Is skin preparation critical when using ENOBIO?
No, the system can be used without the usual skin preparation (scrubbing). Preparation for an EEG measurement is very simple, just put on the head band and ensure good contact between the electrodes and the skin. For the DRL add a small amount of gel.

What is the battery life of the ENOBIO kit?
The current configuration streaming four data channels continuously at 250 SPS has a battery life of >8 hours on a full charge.

Can the ENOBIO be charged from a car plug?
No, the ENOBIO Power connector must be used only with a compatible Lithium- Polymer battery charger.

What does the ENOBIO software do?
ENOBIO software is an application that manages:

• Wireless communication between the ENOBIO and the Host computer
• Data recording
• Data display

Can the enobio be integrated in custom applications?
An ENOBIO API is provided to be integrated to any software development.

What operating systems are compatible with the ENOBIO software?
ENOBIO is currently available for Windows (XP, VISTA and Windows 7) and MAC OSX (Snow Leopard and Lion).

What is the data format of ENOBIO?
ENOBIO writes data to a simple ASCII file of tab delimited columns.
An EDF version will be available soon.

Can ENOBIO data be accessed by other applications?
Yes, the ENOBIO software provides a TPC/IP socket in order to stream data to any TCP/IP capable application in real-time.

In what data format is the raw data streamed?
Raw data is transmitted according to the Starlab Datagram Protocol.
You can find the latest version of the protocol here.

What is the maximum SNR?
ENOBIO Signal-to-Noise Ratio (SNR) is 83dB.

What is the smallest measurable signal that can be measured by ENOBIO?
The smallest measurable signal is determined by the amplifier noise level. ENOBIO amplifier noise for low frequencies is 0.5 μV p-p

What is the resolution of ENOBIO in µV?
The resolution is 0.589µV

What is the input noise?
The background EEG noise is 10-100 µV which is much higher than the ENOBIO amplifier noise. ENOBIO electronic noise adds only a few percent to the total noise level.

What is the dynamic range in bits?
The dynamic range is 16bits.

What is the “effective” dynamic range in bits?
The ADC dynamic range is 16-bits, but ENOBIO includes an analogue gain of 70; in order to compare this dynamic range with another system without analogue amplifier we can consider that the effective bit resolution of ENOBIO is

Is the Driven Right Leg circuit contact important?
Yes, the DRL contact is most important for high quality measurements. Please follow the electrode procedures to achieve best performance.

Is the Driven Right Leg circuit the Common Mode Reference?
Yes, the DRL provides a common reference point between the body and the ENOBIO circuitry.

What is a differential reference?
Every electrode can be used as a differential reference for the rest of the channels; the choice is made entirely in software.
When no reference is selected in software, the signals are displayed with respect to the DRL electrode.
The use of a differential reference improves the CMRR of the measurements.

What is the lowest frequency measurable with ENOBIO?
ENOBIO allows measurement of signals from DC to 125Hz.
The innovative and patented ENOBIO offset control circuit expands the low frequency domain to true DC.

What is the Analogue bandwidth of ENOBIO?
The analogue bandwidth of the signal is DC to 50Hz.
The corner frequency (-3dB) is 30Hz.

Does ENOBIO have adjustable filters ?
Yes, the user interface allows the user to select a digital filter implemented in software.

Does ENOBIO have variable sample-rates?
No, ENOBIO uses a sampling rate of 250Hz per channel for countries with power lines of 50Hz and 240Hz for countries with power lines of 60Hz. These samplings rates are selected to avoid the aliasing of the residual power lines harmonics. If you would like to use different sampling rates please contact to ENOBIO support team.

Does ENOBIO have adjustable Analogue Gain?
No, the ENOBIO is provided with a fixed analogue gain of 70.
This value is selected to accommodate large artefacts and electrode drifts without loss in signal performance. It is possible to order electrodes with higher gains for especial applications. If you would like to explore a better SNR at the ADC stage please contact the ENOBIO support team.

What is the electrode impedance?
The DC impedance of the electrodes is 62GOhm, but the impedance is not the best measure of dry electrode quality. Common-Mode Rejection Ratio is a better measure of the electrode quality. ENOBIO provides 92 dB of CMRR.