📈Part 3: EEG Mac & Task PC Setup

I. Check Impedance

1. Plug in the connector with the wire pointing down. The lock mechanism should be pointing left to open, and turned right to lock and close.

   

ALWAYS ENSURE THE KNOB IS IN THE OPEN POSITION (LEFT)! Do not insert the connector if the knob is on the closed position (RIGHT)

1. Open NetStation Acquisition on the EEG Mac by selecting the blue-colored Acquisition app icon, third from the left in the Home bar.

   • Mac Password: geodesic

   
2. Enter the participant ID: 19XXX

   

   Ignore the ID formatting in this animation.
3. Turn on the EEG stream.

   • In the top left corner, select the On/Off toggle for streaming the EEG signals.
   • Allow the signal to cycle once before moving to the next step.
4. Select the omega “Ω” symbol in the bottom left corner.

   • This will open the Impedance Screen

     
5. Switch the Participant to the Mac.

   • Locate the display switch under the researcher screen and press the Select button located on the right side of the device. The red light should be lit up on Option 2, not 1.

     • Participant PC : Option 1

     • EEG Mac : Option 2

   
6. Identify and adjust the high-impedance electrodes in red and yellow. We want to keep the impedance under 100kΩ for every electrode. Refer to the color legend in the righthand column. Ideally, all electrodes are either green or blue.

   

   • First try moving the electrode around to contact the scalp. Then try pipetting electrolyte solution.

   • Fill a pipette with electrolyte solution and add a few TINY drops onto the sponge of the electrode.

     

AVOID ADDING TOO MUCH SOLUTION! This will soak the patient's scalp and cause bridging between electrodes!

1. Try to adjust as many electrodes as you can, but spend no more than 10 minutes doing so.

2. Once you are satisfied with the impedance values, select Save.

   • You will have to re-check impedances at certain checkpoints throughout the session (📍 IMPEDANCE CHECKPOINT.)

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II. Run EyesOpenEyesClosed

1. Switch the participant monitor to the Task PC.

   • Locate the display switch under the researcher screen and press the Select button located on the right side of the device. The red light should be lit up on Option 1, not 2.

   
2. Run EyesOpenEyesClosed

   • In this task, we're measuring the subject's resting state brain wave data.

   • Open Task Folder on the Task PC Desktop by selecting tree icon titled Session 3. You will run 3 tasks in total:

     • EyesOpenEyesClosed

     • Sustained Pitch Discrimination

     • Sustained Duration Discrimination

   

   • Enter Participant ID and Session Number (always 1).

   • The EEG will automatically start and stop recording on its own. Once the task is started you do not need to worry about starting and stopping the recording.

   • Task Timeline:

     • EEG START Eyes Open - 10 minutes of the participant with their eyes open

     • EEG STOP Pause - participant is presented with new instructions for the eyes closed segment

     • 📍 IMPEDANCE CHECKPOINT

     • EEG START Eyes Open - 10 minutes of the participant with their eyes closed

     • EEG STOP The EEG will stop

     • 📍 IMPEDANCE CHECKPOINT

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III. Run Sustained Pitch Discrimination

1. Click 'Start a New Study' Once the subject finishes the EyesOpenEyesClosed task, the EEG will automatically stop and prompt you to either Close or Start a new Study. To restart the EEG for this Sustained Pitch task, select 'Start a New Study'

   ALWAYS restart EEG before running the next E-Prime task!

2. Enter the participant ID: 19XXXp (p for pitch, d for duration)

   

   Ignore the ID formatting in this animation.
3. Run Sustained Pitch Discrimination

You know the drill from here 😉

• In this task, the participant must discriminate between two tones of differing pitches, and select the tone (first or second) which is higher in pitch.

• Enter Participant ID and Session Number (always 1).

• The EEG will automatically start and stop recording on its own. Once the task is started you do not need to worry about starting and stopping the recording.

• Task Timeline:

  • Thresholding Practice - practice discriminating between 2 tones separated by 500 ms for 5 trials

  • EEG START Thresholding Procedure - discriminating between 2 tones separated by 500 ms to determine their pitch discrimination threshold in Hz for 64 trials

  • EEG STOP Pause - participant is presented with new instructions for the Interval Procedure

  • 📍 IMPEDANCE CHECKPOINT

  • Interval Practice - practice discriminating between 2 tones separated by varying intervals for 5 trials

  • EEG START Thresholding Procedure - discriminating between 2 tones separated by varying intervals to determine their pitch discrimination threshold in Hz for 64 trials

  • EEG STOP📍 IMPEDANCE CHECKPOIN

Offer a short break to the participant (have them remain seated) before starting the next task.

IV. Run Sustained Duration Discrimination

1. Click 'Start a New Study' Once the subject finishes the Pitch Discrimination task, the EEG will automatically stop and prompt you to either Close or Start a new Study. To restart the EEG for this task, select 'Start a New Study'

ALWAYS restart EEG before running the next E-Prime task!

1. Enter the participant ID: 19XXXd (d for duration, p for pitch)

Ignore the ID formatting in this animation.

1. Run Sustained Duration Discrimination.

• In this task, the participant must discriminate between two tones of differing durations, and select the tone (first or second) which is longer in duration.

• Enter Participant ID and Session Number (always 1).

• The EEG will automatically start and stop recording on its own. Once the task is started you do not need to worry about starting and stopping the recording.

• Task Timeline:

  • Thresholding Practice - participant practices discriminating between 2 tones separated by 500 ms for 5 trials

  • EEG START Thresholding Procedure - participant discriminates between 2 tones separated by 500 ms to determine their duration discrimination threshold in Hz for 64 trials

  • EEG STOP Pause - participant is presented with new instructions for the Interval Procedure

  • 📍 IMPEDANCE CHECKPOINT

  • Interval Practice - participant practices discriminating between 2 tones separated by varying time intervals for 5 trials

  • EEG START Thresholding Procedure - participant discriminates between 2 tones separated by varying time intervals to determine their duration discrimination threshold in Hz for 64 trials

  • EEG STOP

1. Ensure that the EEG has stopped recording before closing anything.

2. Close NetStation before disconnecting the net from the amp.

   NEVER disconnect the net before closing Netstation!

3. Put the connector back into the ziplock bag before handing to the participant.

   NEVER handle the connector without a ziplock bag!

4. Wrap-Up

   • Once more, ensure that the EEG has stopped recording before closing anything. The EEG should stop recording by itself. Close NetStation before disconnecting the net from the amp. Put the connector back into the ziplock bag before handing to the participant.