Two researchers work together to position an EEG net on a teenage boy's head. One sits next to him as he watches a video of a bird, and the other person, Dr. Caitlin Hudac, sits nearby to monitor the readout of brainwaves on her computer screen. Video repeats.
Thirteen-year-old AJ Peterman settles onto the couch to watch a video. “Oma” is in the next room playing with his little brother. Mom is watching from the loveseat nearby. He feels right at home and comfortable, even with the net of electrodes pressing through his hair.
AJ is undergoing his eighth electroencephalogram, or EEG, as a participant in a study led by psychologist Caitlin Hudac, an associate professor at the University of South Carolina. Hudac is measuring AJ’s brain’s electrical activity as he repeats different tasks, like watching a video or interacting with another person.
About a year ago, AJ’s mom Akira Peterman learned about Hudac’s lab at USC, Brain Research Across Development (B-RAD), and got involved.
“I was looking for different resources for autistic kids, because out here in Sumter, there’s not a lot for them to do,” Peterman says. “In raising AJ, it helps a lot to have this resource because it helps me to understand him better – what he’s thinking and feeling.”
AJ and his youngest brother are both autistic, and Akira says connecting with the B-RAD lab has allowed them to meet other families in the autism community. But driving from Sumter, South Carolina, to Columbia takes a significant investment of time for the Peterman family.
That’s why today Hudac and her team have packed the equipment into two big suitcases and set up the lab in AJ’s living room. Mobile EEG testing is a process Hudac has refined since she first took her lab on the road due to pandemic-era restrictions in 2020.
At that time, Hudac was a faculty member at the University of Alabama and had grants to study children with rare genetic disorders. The plan had been to fly these families to Tuscaloosa to participate.
“But COVID shuttered that opportunity,” Hudac says. “So, I packed up my EEG equipment, drove around the country and saw more than 55 people in about 90 days.”
This road trip transformed how Hudac approaches testing. Her participants with rare genetic disorders (specifically GRIN2B, SCN2A or SETBP1), deal with complex medical symptoms including epilepsy, motor and cognitive delays, and often autism. Hudac found that visiting the families at home makes the testing experience much better for these kids, who benefit from being in their own environment without the stress of travel.
“I can test the same exact brain measure, and the kids are just so much more relaxed when they’re sitting on their own couch with their dog at their feet,” she says.
Research assistant and lab coordinator Ashlan Cheever (2024 B.S., psychology) started working with the laboratory as a junior at USC. “Showing up to the family's home is always exciting," she says. "You’re going into someone's home, you're meeting their entire family, all the pets, all the siblings. It can be a very intimate experience, but it's so special.”
Similarities and differences in autism
AJ Peterman has not been diagnosed with one of these rare conditions, but Hudac also tests people with and without autism to make up comparison groups for her research on genetic disorders. By comparing EEG measurements in people of a variety of ages, with and without certain diagnoses, the research will help scientists to understand how these rare conditions affect development and why they are linked to autistic symptoms.
AJ will serve as the comparison for Hudac’s current study funded by the SETBP1 Society and the Orphan Disease Center. In addition to testing individuals in the comparison groups, Hudac’s team has recently traveled as far as Texas and New England to test children with the SETBP1 gene variant. In the future, they’d like to travel internationally to reach even more people with rare genetic disorders, but participants like AJ are also key to getting the full picture.
“We are basically trying to match our rare genetic kids to other kids in the community,” Hudac says. “It’s a two-way street of knowing how the brain is working in autism as well as how these rare genetic conditions might look a little different.”
Hudac hopes her research will help to identify subtypes of autism and contribute to a more complete understanding of the autism spectrum, even in cases where a specific genetic link has not been identified.
“There's a lot of evidence to suggest that all autism is genetic. It's just a matter of have we discovered it or not,” she says. “We currently know about a quarter of autism cases are linked to a known genetic etiology, which is important to emphasize.”
Expanding access and understanding
Since coming to USC in 2022, Hudac has found an environment of collaboration and support. She currently serves as steering director for Carolina Autism and Neurodevelopment research center and on the executive committee for the Institute for Mind and Brain. With colleagues working on these questions from different angles and disciplines, the center is making rapid progress on learning about various genetic conditions related to autism, such as Fragile X.
“This is one reason why I'm so excited to be a part of CAN. I can learn from all our partner biologists, neurologists and School of Medicine researchers to understand at the cellular level what's happening in brain development,” she says.
Hudac’s contributions earned her a 2024 McCausland Faculty Fellowship from the College of Arts and Sciences, which provides funding for three years to expand her research. She says the fellowship has served as a bridge to reach kids like AJ in her work.
“I wouldn’t otherwise have funding to come here, today,” she says. “The fellowship helps us support things like offsite testing. It lets us demonstrate the fact that mobile EEG works.”
Hudac aims to have the B-RAD lab offer mobile EEG testing not only for her participants with rare genetic conditions, but for anyone who has difficulty traveling to the lab’s location at USC. This option would help to include more people who live in rural and underserved areas and who face barriers like travel insecurity and long commutes.
“They're not going to come to be in science otherwise. By using mobile EEG testing, I think we're gaining momentum, and it will increase representation even in our neurotypical samples,” she says. “We think science needs to see all people in order to make conclusions about what's going on in the brain and body.”