All in the eyes
Vincent Curtis, a Ph.D. student in the Department of Applied Physical Sciences, uses light to monitor arousal with new technologies that could one day assist patients affected by neuropsychiatric and neurological disorders.
The human brain is undeniably powerful, containing billions of neurons that collect, process, and react to the world around us. When we encounter a particularly impactful stimulus (such as a loud noise in the night or the smell of our favorite food), several distinct populations of these neurons fire accompanied by fluctuations in heart rate, respiratory rate, and pupil size in a process known as the physiological arousal response. Imagine being able to understand how those neurons drive complex behaviors by observing these simple arousal responses. Although the idea seems to be straight from a sci-fi movie, one University of North Carolina at Chapel Hill graduate student is leading the development of optical technologies to monitor arousal metrics with new devices and algorithms that in a not-so-distant future could assist patients living with neuropsychiatric and neurological disorders.
Vincent Curtis, is a graduate student in UNC-Chapel Hill’s Department of Applied Physical Sciences under the mentorship of Dr. Nicolas Pégard. Curtis specializes in computational biophotonics, an interdisciplinary research field at the intersection of biology, photonics, and computer sciences. To broaden his training towards neuroscience research applications, Curtis is also co-advised by Dr. Jose Rodriguez-Romaguera, a translational neuroscientist in the Department of Psychiatry. He collaborates regularly with colleagues across both labs to spark innovative ideas for his research. In his doctoral research, Curtis designs and tests optical instruments to observe and manipulate the activity of neurons, and also to monitor arousal levels from biometric measurements across both mice and humans.
“We can use sculpted light in many different ways to access neurons effectively,” says Curtis. “With light, we’re able to be relatively non-invasive and target very specific arrays of neurons in the brain. We can activate neurons, observe behavioral output and then see what those neurons are responsible for.”
Curtis’ research focuses on developing custom hardware and advanced computational methods to probe neural circuitry beyond the capabilities of existing brain-interfacing instrumentation. He uses arousal metrics, studying pupil size, heart rate and respiratory rate to correlate arousal with the activity of neurons in the brain. His research could have a significant impact on those suffering the burden of neuropsychiatric and neurological disorders, including PTSD, autism, attention-deficit/hyperactivity disorder and cerebral palsy.
“If we had full control over neurons while simultaneously tracking arousal, we could prevent panic attacks in people suffering from anxiety disorders,” adds Curtis.
Curtis also designs computational models for optical systems, develops 3D resin housing for optical components and collaborates with fellow neuroscientists, physicists and computer scientists to create integrative neural interfaces.
“One of the really interesting aspects of our labs is the general philosophy of taking all the available information you have and then finding clever ways to extract more,” says Curtis. “I like the idea of being able to take a technology that already exists, and by looking at it from a different perspective, find a way to hack it in a way that gets us more information, or new functionalities. We all have our main projects, and then we collaborate on larger projects. We meet each week to see where everyone is and where we can give each other input on different ideas. We’re always in one another’s offices to brainstorm. We’re very open, and we’re all very motivated.”
Curtis has been honored for his work multiple times already, including winning the recent APS Research Symposium poster competition. Together with Neuroscience graduate student Maria Ortiz-Juza and mentors Pégard and Rodriguez-Roamguera, Curtis developed biometric ocular photometry, a patented optical technology that tracks biometric indicators of arousal. Their method relies on low-power infrared light diffusing through tissue to illuminate the back of the eye and quantify changes in pupil size, tissue dynamics, and blood flow that affect the amount of light emitted from the pupil and can be measured with a simple photodetector array. They have already demonstrated that their system can collect several arousal biometrics in real-time with better sensitivity than existing techniques.
Curtis, Ortiz-Juza and their co-advisors Drs. Pégard and Rodriquez-Romaguera, along with clinician colleagues Dr. Rebecca Grzadzinski and Dr. Anthony Zannas, were recently recognized as UNC Neuroscience Center NeuroSpark Award winners for developing a pipeline to take their technology from preclinical mouse models all the way to human applications. The NeuroSpark Awards provides $25,000 pilot grants to increase interdisciplinary collaborations throughout the neuroscience community at Carolina.
“We’re very excited about winning,” says Curtis. “It’s good to see people interested in the technology, because ideally this technology system is fairly easy to develop, and we want to distribute this to neuroscience labs so they can integrate it into their own research. Drs. Pégard and Rodriquez-Romaguera are both very brilliant scientists, and it’s nice that I’m able to get advice from someone on the neurotechnology development side as well as on the neuroscience application side. Learning more about the science behind what I’m doing has been incredibly valuable.”
Curtis is also a UNC Royster fellow, a competitive doctoral recruitment fellowship at Carolina. Fellows receive funding as well as interdisciplinary learning and teaching, networking, service to campus and community, professional development, and social opportunities.
“The fellowship is very nice because it allowed me to jump into my research quickly, and I could just focus on my work in the lab, which was super valuable,” says Curtis. “I was able to produce my first paper in my first year because the fellowship allowed me to focus just on my work.”
Curtis sees himself always working in biophotonics or at least in neurotechnology. He’d also like to integrate his early work in holography because with “better holograms, the more neurons can be targeted more specifically,” he adds.
And could he ever use his academic research in arousal metrics as a superpower to tell if friends or family are lying or providing a cover-up? “In my personal opinion, I think lying is too complicated,” he laughs. “There are many variables that go with lying.”
For now, he’ll just stick with neurons.