Kenyon Psychological Neuroscience Lab

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kpnl:acq_day_procedures

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Table of Contents

Before the participant arrives

  • Swap out the amplifier battery with the fully charged battery on the charger
  • Confirm that headcaps and electrodes are clean and dry
  • Prepare supplies
    • Fill syringes with SignaGel
    • Double adhesive collars
    • Cable wraps
    • Paper towels
    • External electrodes
  • Check that the head caps and electrodes are clean and dry
  • Test Button-box
    • 0_dio_test.psyexp
  • Test DIO codes
    • 0_dio_initialize.psyexp

When the Participant Arrives

  • Have the participant read and sign consent form
    • Use the correct form depending on whether they want SONA or monetary compensation
    • Don’t forget you need to sign the consent form too
  • Describe an overview of the procedure and experiments
  • Ask the participant to complete the STAI questionnaire
    • Put the completed questionnaire under my door (or through the mail slot)
  • Make sure the participant understands the length of time they will be in the experiment and ask if they’d like to use the restroom
  • No chewing gum, hair down evenly, no hoodies
  • Electronics should be left outside the recording chamber
  • Jewelry should be removed, but can be put on the side table in the recording chamber
  • Log arrival time

Participant Preparation

  • Determining proper head cap size: measure in cm
    • Measure head circumference just above the eyebrows and over the inion
      • 54-58 cm: Medium Cap (RED)
      • 56-60 cm: Medium/Large Cap (RED and BLUE)
      • 58-62 cm: Large Cap (BLUE)
  • Apply external electrodes (this can be done before the cap if necessary)
    • Be sure the electrode collars are not covering the active part of the electrode
    • Reference
      • EX1 left mastoid
      • EX2 right mastoid
    • Horizontal electroculogram
      • EX3 next to left outer canthus
      • EX4 net to right outer canthus (if applicable)
        • See here for approximate location.
    • Vertical electroculogram
      • EX5 and below the left eye
      • EX6 (if applicable) above the the left eye
        • See here for approximate location.
  • Put on cap
    • If the participant requires glasses, have them wear them during cap fitting
    • Visually inspect the cap to ensure it is on straight
  • Determine proper vertex location (i.e., electrode Cz)
    • Anterior/posterior - Measure nasion to inion (divide by 2)
    • Left/right - measure from left to right preauricular area (divide by 2)
    • Double check that the cap is still straight now that you’ve made your adjustments
  • Ensure that the cap’s tag at the O1, Oz, O2 electrodes is pulled out
  • Apply gel to cap electrode holders
    • Build columns of gel: fill from syringe, move hair around
    • If participant is bald or has very short hair, start with minimal gel to avoid pooling
  • Insert electrodes into cap
    • Be very careful not to stress the electrode leads where the wire meets the electrode
  • Wrap CMS/DRL three or four times around ribbon cables & EX leads
    • Secure with cable wrap at nape of neck and also below the wraps
  • Bring the participant into VERONICA

Electrode Testing

  • Attach the ribbon cables and EX leads to the amplifier
    • Be mindful of correctly aligning the connectors to their respective ports before you apply pressure
  • Attach the battery to the amplifier and turn on the power
  • Ensure the amplifier’s solid blue light is on indicating CM in range
  • Select the Electrode Offset tab in ActiView
    • Check all 64 channels and also EX 1-6
    • Electrodes should be should be between +/- 40 mV and not bouncing up and down
    • If electrode is outside of range:
      • Try adding a bit more gel and parting hair with the syringe
      • Ensure the electrode is firmly in place
      • If many (all) of the electrodes are out of range, check CMS & DRL
      • Select the Monopolar Display tab in ActiView
    • Look for channels that are drifting or seem particularly noisy
    • Use same techniques above to correct bad channels
    • Return to Electrode Offset tab and ensure all electrodes are still in range
  • Show the participant their alpha waves, EMG, and eye-blinks.
    • Use this opportunity to emphasize why being relaxed, comfortable, and still is so important and why they should try to avoid blinking outside of the specified “blink times”
  • Turn ON and test intercom system
    • Turn ON by pressing talk button
    • Turn on Monitor Mode on the VERONICA intercom by pressing the Monitor button until you hear a tone
  • Place the LCD display such that the participant is ~70 cm away and that top of the display is roughly at the eye level of the participant.
  • Give the participants a few minutes to acclimate to the dim environment inside VERONICA before beginning the first task.
    • Do the same whenever you’re transitioning from between bright and dim tasks (e.g., from a paradigm that uses the anaglyph glasses to one that does not)

Data Acquisition

  • Select Start File button on lower-right side of ActiView Screen
  • Select OK on the pop-up window
  • Specify the filename
  • At this point the file has been created but is not recording
    • The stimulus computer will trigger the recording at the start of the experiment
  • At the end of the experiment press Stop

After the Experiment

  • Turn off power and disconnect the battery from the amplifier
  • Disconnect the electrodes from the amplifier
    • Press the white tabs to remove the ribbon cable connectors
  • Carefully remove the cap and EX electrodes
  • Set cap and electrodes aside
  • Debrief the participant
  • Compensate the participant
  • Turn Wi-Fi back on (stimulus control and EEG acquisition computers)
  • Restart Google Drive (stimulus control and EEG acquisition computers)

Cleaning Up

  • Remove the adhesive collars from the EX electrodes and set aside
  • Remove the EEG electrodes from the cap
    • Do not pull on the lead or cause any strain where the lead connects to the electrode
  • Fill a plastic bucket with warm water (never hot) and submerge the electrodes
    • Be sure that the connector end of the lead is kept dry!
  • Clean the electrodes in the water
    • Avoid touching the active part of the electrodes
    • The electrodes are clean when they no longer feel slimy (no more gel residue)
    • Set electrodes on a wee-wee pad to dry
      • Splay them out and untangle any tangled leads
  • Clean the gel out of the electrode holders by spraying water through the holes
  • Clean the cap in a bucket of warm water
    • A small amount of Dove soap can be used
kpnl/acq_day_procedures.1488230682.txt.gz · Last modified: 2017/02/27 16:24 by admin
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