COVID safety notes


Being prepared

Paperwork to have ready:

Important Supplies:

First Steps:

Put your phone on silent


Setting Up the Pariticipant

When the participant arrives, ask them to remove all electronics (i.e. phones, watches, earbuds, etc.) and store them in a safe space.

Give the participant the informed consent sheet and any other paperwork that needs to be done at this time.

Using the tape measure, have the participant hold the start of it in the center of their forehead, just above the eyebrows. Make sure that the bottom of the tape measure touches the tops of the ears and the inion. Write down the total number in cm (this measurement will tell you if they require a S, M, or L cap).

Have the participant hold the tape measure against their nasion (an indent just below the eyebrows) and go over the top, center of their head until you reach the inion (a bump at the lower, back part of the skull). Take 10% of that number, then measure that distance on the participant's forehead and mark it with a grease pen (this will be a reference for where the front of the cap should be placed).

nasion and inion 1.jpg

Guide the participant into the EEG study room and check the EEG cap log to make sure to use the least recently used cap in that size.

Have the participant brush through their hair with a disposable comb and clean off their face with a towelette (specifically on their nose and around their eyes, as electrodes will be placed there).

With the proper cap, have the participant sit still. Align the front of the cap with the grease mark using your thumbs along the front edge to hold it in place, and assure that the central electrodes are lined up with the center of their head. Pull the cap over their head using the rest of your fingers.

Have the subject hold the cap connector

Remove the backside of the sticky disc and apply each electrode

Have the participant face the monitor, and adjust the chair and the chin rest so that they are in a comfortable position. Be sure that it is a position they can stay in comfortably for an extended period of time, as we want them to be comfortable during the experiment.

When they are comfortable, connect the cap connector to amplifier and turn the amplifier on.

Testing and reducing impedance

On subject monitor, hit: source, down arrow to DVI, Menu. This will connect display to Amy so that impedances can be checked from subject room.

Prepare for new acquisition:Open Curry 8oDUnder database pane

Under acquisition pane, (amplifier control tab already open) verify amplifier = SynAmps2/RT, configuration = RefRemyourstudyconfig, sample rate = 1kHz.

Back to Amplifier control tab

You should see the impedance chart on the monitor. They will all show high impedance at this point. Only the electrode sites to be used in the current study will appear.

Explain the syringes to the subject, show them that they are not sharp. Tell them that we will be filling each electrode with a small amount of gel and in order to establish a good connection, will be wiggling the end of the syringes or a wooden swap in the electrode to move hair and allow gel to contact the scalp. We will be swirling firmly, however if it becomes uncomfortable, the subject should let us know!

Start by putting gel in the Ground electrode and another electrode for example CZ (select an easy one from the screen’s chart, usually one relatively unobstructed by hair). These plus the references, which should already have decent connection since they were resting before the experiment began, are important in establishing a good baseline. Once the third electrode (CZ) has been gelled, it’s impedance should be lower.

Try to achieve <5 kΩ on the third electrode by continuing the swirling action. If it won't go lower than 5 kΩ, the ground and references should be tried again. It is important to establish these 3 electrodes below 5 kΩ before moving on to the others.

Make one quick pass over each other electrode, filling with gel and swirling just enough to see its impedance jump lower, then move on to the next. Once all electrodes have been gelled, return to them and continue the swirling motion.

Switch subject monitor back to HDMI (Kif), and begin the experiment.

If eye tracking is used in the study, refer to StandardEyeTrackingProtocol


EEG Data Collection Checklist

Practice Run

First Experimental Run

Second Run Onward


Cleaning Up

After stopping recording on last session, also click on stop amplifier. Carefully disconnect cap from amplifier, hand connector end to subject, and lead back out to the setup area. Remove chin strap. Disconnect face electrodes carefully, slowly peel sticky discs away from skin. Gently remove the EEG cap and place in sink ensuring that connector is not in danger of getting wet at any point. Offer participant another towel, hair dryer, bathroom break, anything else they need before wrapping up paperwork and debriefing. When participant is ready, do remaining forms: Derryberry, vocab. LTM?? Give participant payment and have them fill out receipt form.Read debriefing script; check if participant has any questions. Thank participant for coming in and show them out.

Shut down computers in the following order:

Needle end of syringes should be disposed of in the biohazard container. Leave remaining gel in syringe, but pull plunger back a small bit to pull gel back from tip.

Throw out any used paper towels, swabs, and other disposable items used in the study

Put any used towels in the laundry basket.

Put measuring tape in the disinfectant bucket.

Remove the reference electrodes from the cap and throw away the sticky disks. Using the water pick, on setting 4, spray the electrode and make sure there is no remaining gel. Spray through the hole as well to make sure its clean. Then, place the reference electrodes in the disinfectant bucket.

Keeping the cap connector away from the water, gently rinse the cap in sink, try to keep its shape without stretching the material.

Turn cap inside out and using the water pick, on setting 4, spray each electrode cup to remove any gel, make sure to move the stream through the hole in the electrode.

Rinse the cap under the faucet once more to remove stray gel. Inspect each electrode and make sure no gel remains! Also clean off any gel that remains on the fabric of the cap.

Remove the measuring tape and electrodes from the disinfectant, and lay them out on paper towels to dry.

Place the cap in the disinfectant bucket for 2 minutes, again keeping the cap connector away from the liquid. Then remove and rinse well.

Cover the foam head with a few sheets of paper towels and place cap on head. Position the cap so that it sits loosely and not bunched up anywhere.

Make sure to log any technical irregularities with the net (bad electrodes, etc.) in the collaborators’ EEG net usage logbook.

If more distilled water is needed (basically if there is any less than a full supply --so probably almost always), distill another batch


"Standard" Processing Steps

rapwiki: StandardEEGProtocols (last edited 2020-12-06 21:52:31 by HannahRoss)