C.4. Check the EOG/ECG Signal

To verify the quality of the EEG signal:

  1. Go to the EEG console in the control room.
  2. Click on the Play button on the Acquire window. You should see the signal from the three channels. If there is not signal, check that all the Synamps (in the equipment room) are ON . Then restart the EEG PC.

    In the background there will be a message stating “Data not Recording”. This is because the data will not be stored on the EEG system, but will be recorded by the MEG system instead.

  3. Check that the signal from electrodes is clear:

    1. To verify the EVOG, ask the participant to blink.
    2. To verify the EHOG, ask the participant to move their eyes side-to-side.
  4. If the eye movements or the cardiac signal are not being detected, check the following:

    1. The leads are properly plugged to the Head Box.
    2. The paired leads are plugged to the same bipolar channel.
    3. The coils are still attached to the skin.
    4. There is enough conductive gel between the electrode and the skin.
    5. There is enough conductive gel between the electrode and the skin.

    If all the above checks fail, try changing the position of the coils.

  5. If there is electric noise, check the following:

    1. The Mastoid lead is properly plugged to the REF position on the Head Box.
    2. The Mastoid coil is still attached to the skin.
    3. There is enough conductive gel between the electrode and the skin.