Connecting Electrodes to Neurobit Optima Devices

The Neurobit Optima devices have electrode inputs on the front face, opposite of the power cable.

Electrode inputs for the Optima devices are arranged in two rows, with the Signal inputs and Ground input on the top row, with Reference inputs on the bottom row.

• Signal inputs are Red and denoted by a + on the device’s top plate.
• Reference inputs are Black and denoted by a - on the device’s top plate.
• The Ground input (also known as ‘Virtual Ground’) is White and denoted by a VG on the device’s top plate.

For single-channel training, the following ports should be used: Ground (VG), SigA (A+), RefA (-A). An example of this electrode configuration is included as reference.

Linking Reference Inputs

By default, the Optima’s reference inputs are internally linked within the software. This allows a user to perform multi-channel training using less electrodes and allows for advanced types of training.

Software linking can be disabled by the user within the EEGer software if necessary (Options>EEGer Configuration Options>Device Optima>34 Link all references). This allows for physical linking to occur with stacking electrode jumpers or allows all channels to operate independently.

Additional Notes

The Optima devices are unique from other amplifiers in the following ways:

1. Optima devices have a Reference input for all EEG channels, whereas most amplifiers combine the Reference input together for multiple channels.
2. The electrodes are arranged from right-to-left, whereas most EEG amplifiers arrange channels from left-to-right. This can be confusing at first, but labels can be found on the top face of the amplifier to help with orientation.
3. There is a blue ‘Shield’ input, used with special electrodes. The electrodes provided by EEG Store do not use this input, and it can be left ‘open’ during training without impacting signal or impedance measurements.

4. The ‘signal’ LED on the amplifier’s top face will reflect the connection of the electrodes during training.

   • No Illumination: Amplifier is not powered on or not being used by EEGer.
   • Green Light: Amplifier has a connection for all active electrodes.
   • Orange Light: Amplifier detects no signal for at least one active input. This may be because an electrode is not properly connected, damaged, or there is an open port on the device (when performing multi-channel training).
   • Red Light: Incoming signal is too large, observed in some cases when measuring impedance, during periods of artifact, or while connecting or manipulating electrodes.

   Full details can be found in the Neurobit Optima Instruction Manual.