Muse User Testing (&Volunteer best practices)
Preparation
Clean and moisten the Muse contacts. Be sure to wipe the rubber earpieces as well as the headband.
>> Experiment with handi-wipes plus additional light saline to improve contact (e.g. contact lens fluid)
Donning
Without practice, it’s hard to get the headset properly positioned. I’ve found that it works better to directly put it on people, to keep them from fumbling around. Here’s a recommended sequence:
>> Try this out with a range of volunteers and subjects to make sure the process is easy to replicate
Calibration
>> Look into a RasPi based calibration device with a small LCD display for the above
>> Consider duplicating this at each exhibit swipe-in station, so the user can check their signal and readjust the headband if needed
Relaxation coaching (overlaps with calibration above)
Calibration is much faster if the subject is physically relaxed. Here are the guidelines I’ve found help the most (speak softly, with 4-5 second pauses between phrases):
>> Try this out with a range of volunteers and subjects to make sure the script is easy to follow
Readjustment and troubleshooting
In a number of cases, the headsets just have trouble maintaining connection. It may have to do with skin type, texture, moisture or what. It seems to help in these cases if you loosen the earpieces a bit, and move the headband up or down to find a better position.
I also found that in some cases it helped to have the participant rub their forehead briskly from side to side, which brings the blood to the surface, and possibly removes some layers of skin oils or makeup.
Doffing
When they’re done, some people need help getting the headset off, not being sure how to get it back up over the ears.
Storage
Find or build some stacking trays with slots to safely store the headsets
Preparation
Clean and moisten the Muse contacts. Be sure to wipe the rubber earpieces as well as the headband.
>> Experiment with handi-wipes plus additional light saline to improve contact (e.g. contact lens fluid)
Donning
Without practice, it’s hard to get the headset properly positioned. I’ve found that it works better to directly put it on people, to keep them from fumbling around. Here’s a recommended sequence:
- Adjust the headband to its widest setting (hold the earpieces one in each hand, and use two fingers on each side of the headband to push it out of the earpieces)
- If they have long hair, ask them to gather and hold it up away from their ears
- If they have glasses with bulky earpieces, ask to remove and replace them after the headband is on
- Set the Muse earpieces down over the back of the ears
- Holding the earpieces firmly down against the back of the ears with your fingers, use your thumbs to gently compress the headband across the middle of the forehead until it’s snug
>> Try this out with a range of volunteers and subjects to make sure the process is easy to replicate
Calibration
- Swipe the headset RFID tag into the calibration station
- Watch the 5 Muse contact indicators, they may take 10-20 seconds to make contact
- Watch the EEG data indicator, it may take another 10-20 seconds to calibrate
- A nice visual effect should start when valid data is being received
>> Look into a RasPi based calibration device with a small LCD display for the above
>> Consider duplicating this at each exhibit swipe-in station, so the user can check their signal and readjust the headband if needed
Relaxation coaching (overlaps with calibration above)
Calibration is much faster if the subject is physically relaxed. Here are the guidelines I’ve found help the most (speak softly, with 4-5 second pauses between phrases):
- Muscle tension in your face and shoulders can interfere with the EEG signal, so it helps if you relax a bit.
- So close your eyes for a moment….
- Let your jaw relax, let your teeth separate a little…
- Lift your shoulders
- Let your breath be soft and steady... (By this time the headset should make contact and be calibrated)
- When you do open your eyes, let your gaze be soft…
- When you need to blink, let your blink be slow and soft…
- Now stare softly into the display and see what your brain is doing.
>> Try this out with a range of volunteers and subjects to make sure the script is easy to follow
Readjustment and troubleshooting
In a number of cases, the headsets just have trouble maintaining connection. It may have to do with skin type, texture, moisture or what. It seems to help in these cases if you loosen the earpieces a bit, and move the headband up or down to find a better position.
I also found that in some cases it helped to have the participant rub their forehead briskly from side to side, which brings the blood to the surface, and possibly removes some layers of skin oils or makeup.
Doffing
When they’re done, some people need help getting the headset off, not being sure how to get it back up over the ears.
Storage
Find or build some stacking trays with slots to safely store the headsets