Saturday, July 9, 2016

The 'joys' of human subject testing

Ah, the joys of human subject testing. Let’s begin with the positive aspects: the process of collecting EEG data from volunteers at IMEC has left me with a new appreciated for biologists everywhere. Sure, circuits and code can break in horrifyingly puzzling, strange, and exasperating ways, but if you follow basic rules and techniques and avoid physically crushing anything you can almost always make machines work. Living beings are a whole different can of worms. If you’re not getting good EEG signal, it could be that the subject’s brain just doesn’t work like you think it does. There could be interference from sweat or hair. They might not be focusing on the task at hand, so you could be recording brain waves related to weekend plans rather than motor intention. Of course, you have all the normal equipment problems on top of biological factors, so your troubles could also be related to battery, wireless interference, loose electrodes, or the ever-fickle gods of engineering.

At this point I’m more than halfway through data collection, so if all goes well I’ll finish up next week. That would leave me with the rest of the summer to work on classifying EEG signals into motor intentions and hopefully use my shiny new data to add a no-movement class. This week I realized I need a way to quantify signal strength, so I’ve been working my way through various MATLAB toolboxes comparing function outputs. My goal is to find a way to exclude bad trials so they don't unnecessarily confuse my classifier.

Outside of work, Lakyn and I went to Paris last weekend! We were fortunate to have my friend Tristan as a native guide; with his help we saw tourist attractions like the Eiffel Tower, Notre Dame, the Arc de Triomphe, and the Louvre, then caught the Pride parade marching down the Seine. That evening we ate in the student quarter, watched Italy play Germany in an Irish pub and danced our way through the night. Despite all that, I think my favorite thing about Paris is the bread. Lakyn and I stopped by a bakery on Saturday morning for a baguette and it was so good I nearly cried.

It’s July 8th now and I can’t believe I’m halfway through my internship. Yesterday I got my cast off and tonight Lakyn, Olli, and I are catching a train to Amsterdam, where we’ll meet my friend Ally and spend the weekend exploring. This whole summer feels like something out of a storybook whenever I stop to process it. I’m planning to make the most of the time I have left by finishing the human subject testing, fine-tuning the gesture classification process, and developing exclusion criteria for bad trials. That’s a reasonably optimistic agenda for one month, and it’s likely I’ll only accomplish two of those three goals. But if I can’t be optimistic during a summer abroad in Europe, when can I?

Lydia Carroll is a 21-year-old biomedical engineer on her first excursion to the European mainland. In her free time she enjoys taking things apart, putting them back together, volunteering with the Maryland SPCA, and reading any paperback novel she can get her hands on. 

Me wearing the EEG headset and recording myself.


The Pride parade marching downtown along the Seine.

Notre Dame

No comments:

Post a Comment