When EEG leads are attached through a cap to the scalp, the visual effect is a cross between a sychronized swimmer and Medusa. The electrodes will painlessly transmit the brain’s electrical activity while different sounds play through the participant’s headphones.
The headphones sound out a random tap-tap-tap, like a hammer on tin. It’s an intermittent din, overlapped and interspersed with buzzes, shushes, whirrs and occasional clicks.
The sound repeats.
Over. And over.
And over again.
Every 10 minutes, postdoctoral scholar Vanessa Irsik pops her head into the soundproofed booth to check that I haven’t fallen asleep, or perhaps to ensure I haven’t carved the words ‘help me’ into the desk.
The noises were not painful – just persistent, like a mosquito in a tent. They were even a bit mesmerizing. Fortunately, during most of this exercise, a muted Frodo and his Fellowship of the Rings kept boredom at bay as they played out their Middle Earth saga on the tiny screen in front of me.
So while I marked time with the Hobbits and did my best not to fidget beneath what looked like a red bathing cap with 16 electrodes sticking out of my head, Irsik was doing the tougher work of checking out my brainwaves on a computer screen outside this little booth.
She will analyze them as part of a larger study to discover how and where young, middle-aged and older brains manage competing messages in a sea of background noise.
After an hour – and at about the same time as Arwen swooped in to rescue Frodo from the ghostly grasp of the Ringwraiths – Irsik opened the door a final time to announce we were done and it was time to remove the gummy electrodes from my scalp.
My brief and painless role as a BrainsCAN guinea pig was all over but the hair-washing.
A choice of movies awaits participants in a BrainsCAN study of how the brain interprets competing sounds. While the movie plays on mute, the researcher plays specific sounds through the participant’s headphones.
* * *
Until a couple of months ago, I would have been unlikely to find Irsik’s study – or any of the others – except by happenstance. Recruiting participants in most fields of study usually takes place by word-of-mouth or through notices on campus notice boards.
Finding volunteers has often been the technological equivalent of the carrier pigeon – even if the message goes out, it’s anyone’s guess how many will see it and respond, in the necessary numbers and demographics, and at the right time.
That’s why researchers in neuroscience, one of Western’s signature areas, recently launched the Cognitive Neuroscience Research Registry, also known as Our BrainsCAN. There, anyone can sign up online to become part of a general database that scientists can then scour for participants who fit their study’s needs. Our BrainsCAN aims to enrol 50,000 participants over a period of five years.
Efforts like these are part of a growing awareness at Western – and beyond – that in order for research to be truly informative, it must also be truly reflective of the world it is attempting to explain.
The traditional method of finding study participants, through bulletin board notices, relies heavily on a potential volunteer happening upon the right study at the right time. The OurBrainsCAN registry aims to be a centralized place where neuroscience researchers and participants can connect
Based on a model used at the University of Pittsburgh, Pitt + Me, which now has about 200,000 volunteer registrants, the registry helps researchers find volunteers who match criteria they’re looking for, and helps participants connect with standardized ethics-reviewed studies.
“It’s a way of ensuring all participants have a similar process,” said Ingrid Johnsrude, Director of the Brain and Mind Institute.
The site includes a full study description for every request, an option to turn down any request and a promise of no known risks, discomforts or direct benefits associated with participation in the registry.
The registry is one way to ensure better science, as it enables representation across ages, genders and conditions. It brings the entire community on board, stressed Johnsrude, who also serves as the Western Research Chair in Cognitive Neuroscience and head of the CoNCH (Cognitive Neuroscience of Communication and Hearing) lab.
“If we want our research to be truly informative about people, we need to include all people, we can’t just test highly educated 18- to 25-year-olds.”
She said OurBrainsCAN is an important way regular people can make a difference in bigger questions of neuroscience.
* * *
Looking to do my part for scientific knowledge – but mostly to appease my curiosity – I signed up with my name, age, rudimentary personal information (left-handed, normal hearing, fluent in English) and email information.
That’s how Irsik found my information as she sought out a wide range of participants for her research.
After an explanation of the research and testing process, Irsik led me into a soundproofed booth about the size of a sauna, with walls lined with acoustic panels that dampened noise inside and out. The room contained a chair and desk, a computer screen and some electronic gadgetry. There was a window in the door.
First, I took a simple sound and hearing test. With a colour-coded headset on (red over right ear, blue over left), I took in hand a clicker resembling the one game-show participants use on Jeopardy! Each time I heard a cicada-like buzz in either ear, I pressed the plunger for the duration of the sound.
It began at forte with a decrescendo to piano, to pianississimo, to nothing.
I second-guessed my perceptions: Did I release the plunger too early? Did I miss that teensiest bit of residual sound? Then the process reversed and I depressed the plunger only when the pitch grew from nothing to something.
The next stage test was a ‘speech-perception task.’ My job was to type the recorded words of a person speaking simple statements, through escalating background noise in my headphones.
It started well. Then, as the din rose, my confidence plummeted. That statement makes no sense, I thought. Did she say ‘dishes’ or ‘fishes’, ‘gift’ or ‘dig’? Was there a verb somewhere in that sentence? Foreground and background noise melded into each other and the result was a nonsensical soup of sound.
Imagine Confucius dreaming up random subjects and predicates, haphazardly stitching them together after waking from a long nap and then whispering them in the subway station at rush hour. You too might wonder if you’d missed out learning the key to happiness while your friends merrily boarded their homeward train.
Irsik told me later, many people get age-related or noise-induced hearing loss in which our ears lose the ability to detect specific pitches or specific sounds. But in many people, it’s not the aging ear that’s at issue but the aging brain. It can detect sounds just fine, but can’t organize them in a way that makes sense.
Somewhere in the brain, the ‘normal’ audio input gets fuzzed, muted, shape-shifted – translated into something like a kazoo rendition of a Mozart concerto.
Irsik is trying to discover exactly where in the brain that ‘somewhere’ is.
* * *
The need for research volunteers is bigger than any one program.
Western doesn’t have a universitywide repository of potential study participants, although different areas do keep lists in their own specialties, such as child-and-youth research or specific clinical studies, said Mark Daley, Associate Vice-President (Research).
“There isn’t a single ‘Gee whiz, I’d love to participate in research at Western’ repository. It’s something we’ve discussed; it’s well worth doing,” he said. “Ideally, you’d build it so it could be used across any discipline.”
University of Calgary has such a registry, which includes research trials and clinical studies in a variety of disciplines, and participation can range from high-tech MRIs to online surveys. Like any large-scale, cross-campus undertaking, the obstacle to creating such a registry at Western has been the availability of resources, he said.
OurBrainsCAN is important for science, Daley said. “It represents a badly needed registry to ensure we have a pool of potential participants selected from a diverse population.”
The bulletin-board method tends to attract mostly students, which can lead to studies that include “a convenient sampling of a segment of the population, by accident.”
By contrast, he said, registries such as OurBrainsCAN can draw on the enthusiasm of a host of volunteers – who just needed a conduit for their willingness to contribute to scientific knowledge.
* * *
A sample EEG (not from this study) shows the electrical signals made by neurons communicating with each other. Each line represents voltage recorded from one electrode.
Now, this was the part where an electroencephalogram (EEG), a study of my brainwaves, entered the picture.
Outside the sound booth once again, Irsik measured the circumference of my scalp and the distance from left ear to right in preparation for this most techy stage of the study.
A red, 16-hole cap was snug-fit to my head and Irsik applied conductivity gel with an applicator and secured the EEG leads to my scalp. She sticks an additional two electrodes just below each ear.
My head looked like synchro-swimmer-meets-Medusa.
She directed me back into the sound room where the other ends of the leads were plugged into a toaster-sized contraption that amplified my brainwaves and recorded them into Irsik’s computer.
Relax, she advised. Sit as still as comfortable, but don’t worry if you wiggle a bit. She closed the door and offered a slight wave through its window.
I pressed ‘Play’ on muted Frodo and the unfamiliar whirrs and buzzes filled my ears.
On Irsik’s side of the sound booth, each electrode from my head translated into a squiggly line on her screen. This was the electrical activity being generated in my brain as neurons signal to each other. And when specific neurons register stimulus, such as the clicks and buzzes, they created specific signatures Irsik will interpret later.
Sixteen electrodes will attach to different areas of the scalp in an electroencephalograph (EEG). The other ends of the leads will plug into a device that records the brain’s electrical signals.
The final four minutes brought an abrupt change of pace. There was a series of rapid and insistent clicks, like someone clicking a pen, 1,000 times per minute. Irsik explained this stimulates the brain stem, where she believes some of this sound perception takes place.
While this test is the shortest in duration, it might also be the most scientifically telling.
To her at least. I’ll never know. All participants’ information is anonymized. She will provide access to the results and paper once the study is complete, likely sometime next year.
Irsik is something of a neuro-research wonk. This is her 10th study project since her arrival at the Brain and Mind Institute a year ago, from the University of Nevada at Las Vegas.
“Even if you don’t find what you think you’ll find, you’re always discovering something interesting,” she said.
That’s a similar sentiment for the other researchers, Johnsrude explained. As each study adds incremental knowledge, we learn more and more about the human brain.
“We’re tackling important problems. The brain is complex and the whole point is understanding the conditions that give rise to thoughts and behaviours.”
Conductivity gel is applied with a syringe to the surface of the scalp so that Postdoctoral scholar Vanessa Irsik of Western’s Brain and Mind Institute can get a good reading of the brain’s electrical signals. The gel washes out easily with shampoo after the test.
* * *
Irsik carefully plucked each electrode from my scalp and peeled the cap from my head before she led me to a private room where a bit of shampoo washed the goop out. She was mum about any details.
My personal data remains just as confidential from me as from everyone else. The data is stored on a secure computer in a locked room, accessible only to the investigators.
What she did show me, though, was a screenshot of 16 squiggly lines that represent my brain’s electric signals. “See that occasional little spike in your top line?” she said. “That’s your eyes, blinking.”
Hidden somewhere in there, ready for an expert to analyze, is a small story of what makes my brain similar to others and unique at the same time.
