IMPEDANCE TEST

Are the Electrodes making good contact?
  Simple Impedance Test: Remove completely from the skin.
Find a greed ground electrode.
Use either the green electrode on the 3-wire EMG/ECG/EEG or the Green finger skin conductance electrode on the SC cable.
Snap on 3 electrode pellets. Put some gel on them to increase conductance.
Touch the positive electrode to the green ground.
The Impedance Bar should go down into the green.
Touch the positive electrode to the green ground.
The Impedance Bar should go down into the green.

If no color change or 'break' continues, the cable or snap connect is cut or degraded.
If not, the problem is in the skin preparation.

Are you really preparing the skin properly?
   Skin can be dry or oily, clean or covered with lotion or makeup. It does not matter. ALWAYS 'abrade' the skin with a pad, using circular motions. And scrub hard - the skin should look red. Use an abrasive lotion. Use alcohol to remove residue, and scrub in circles with a dry pad. The idea is to remove dead skin.
Ready? Do not put the electrodes on yet. Use a cue-tip to put a dab of electrode gel on the spot where the electrode will be placed. Spin the gel into the skin.
Place the pre-gelled electrodes over the sites and ask the client to press hard around the edges.
Now test impedance.
Remember that impedance is proportional to the the degree that the gel merges with the skin. Often as the skin warms the gel makes better contact and impedance improves over 5 or 10 minutes.

Low EEG Impedance is most critical!

Poor EEG impedance .Will generate artifact that is amplified in the low delta-theta frequencies. Your 'neurofeedback' training could be biased, giving false 'theta' bursts. EEG impedance

Check impedances
- verify signals.

IMPEDANCE:  Would you start a journey without checking the road conditions? Poor impedances will provide false signals and get you lost.

IMPEDANCE: Ensuring a Good Connection
In every application session, the first screen you will see is the Sensor Test Screen. Hook up the sensors using the picture as a guide.  Please refer also to your Hookups  Guide for information on cable/electrode configurations for your device and connection tips for different modalities.