To ensure that a client is not training to something other than EEG, EEGer will go into artifact suppression mode if it detects artifact (signal noise). If there is a lot of noise, and the amplitude of the raw uppermost trace is exceeding its thresholds, EEGer will stop sending information to the reward and inhibit traces. You should still be able to see a noisy signal in the raw EEG trace, but the filtered reward and inhibit traces should look like a flat line.

Excess artifact in the raw EEG can come from a variety of sources. Muscle tension and other sources of EMG are the most likely sources of artifact. Ensure the client is sitting still and relaxed. Check that they are not creating excess artifact (signal noise) in this relaxed state.

If your connection is poor, this can also introduce artifact, but it should be easy to diagnose because your impedance will be high in this situation. This knowledge base article has more information on improving your connection and impedance.

Outside electronic devices, especially smart phones, can create artifact. It is advised to have any smart devices switched to airplane mode or simply turned off during a session.

If muscle tension is clearly not the issue, the thresholds may be set too low. When the thresholds are set low and the EEG signal is larger than the thresholds, EEGer will interpret the signal as artifact and filter it out.

You can manually adjust the threshold using the arrow keys on your keyboard. Use the up and down arrow keys to select the raw EEG trace, then use the left and right arrow keys to raise or lower the threshold until you see an EEG signal in the reward and inhibit trace.

Generally speaking, you should not need to set your thresholds above 60uV. Be advised that higher thresholds will allow noise and artifacts into your data, meaning that you will be training artifact like muscle tension in addition to EEG/brainwaves.

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