A typical surgically implanted electrode gives neuroscientists and clinicians a glimpse into the brain’s inner workings. Yet it’s a narrow view, akin to looking at a few pixels of an image with no sense of the larger picture.
Hai is developing those next-generation tools—ones that can work wirelessly, that don’t require major surgery, and that can reveal a more comprehensive account of neural activity across regions of the brain. Hai, who came to UW-Madison after completing his postdoctoral research at Massachusetts Institute of Technology, creates electrical, magnetic and electromagnetic sensors, including ones that work with existing technologies such as magnetic resonance imaging (MRI) and magnetoencephalography (MEG).
“I am trying to revolutionize the way we acquire signals from the brain,” he says. “For a few decades, we’ve been able to record and stimulate from very localized areas. And I think it’s like measuring a little drop of water in an ocean of activity. You have tens of billions of units and orders of magnitude more connections. We don’t have the technologies to understand the brain. I think neuroscience is stuck. There’s a lot of good research, but we need better tools.”
Hai detailed one of his novel devices in an October 2018 paper in Nature Biomedical Engineering: a wireless sensor capable of identifying electromagnetic fields in the brain that can then be detected using MRI.
He’s also used nanofabrication techniques to create cell-sized electrodes with unique topography that encourages closer connections with neurons, which exponentially amplifies signals. And Hai has applied molecular-based sensors, proteins designed to bind to neurotransmitters in the brain and show changes via MRI. He’s deployed the latter to view the effects of antidepressant drugs on serotonin and dopamine levels across large volumes of the brain in rats.
“We’re creating a new toolbox,” he says.
Hai’s arrival bolsters the Department of Biomedical Engineering’s growing strength in neural engineering. Hai, who’s also part of the Grainger Institute for Engineering at UW-Madison, joins Vilas Distinguished Professor and department chair Justin Williams, a pioneer in the field, and Associate Professor Kip Ludwig, an expert in devices that stimulate the brain who came to UW-Madison in the summer of 2018.
“It was clear that I have everything I need here scientifically,” says Hai, who also envisions collaborating with Professor Walter Block, an authority on MRI, as well as faculty in electrical and computer engineering, neuroscience and chemistry. “There’s a surge of neuroengineering here right now.”
It’s an ideal environment for someone who’s been captivated by neuroscience since age 15, when, flipping through a newspaper in his native Israel, he saw an image of a neuron growing on a microelectronic chip, part of a study by German biophysicist Peter Fromherz. “It sparked my imagination,” says Hai, who then began reading about the brain, neurobiology and consciousness and later met Fromherz as a PhD student at the Hebrew University of Jerusalem.
Hai hopes to pass on that zeal while teaching Introduction to Biological and Medical Microsystems and part of the biomedical engineering department’s design sequence, starting in fall 2019. He says he’s a firm believer in not just instilling fundamental knowledge, but also familiarizing students with the latest technology.
“I think it’s very important to educate students about what’s happening right now,” he says.
For Hai, that will mean showcasing his own solutions to seeing a fuller picture of the brain.
“I’m very focused in solving this problem,” he says. “I think it’s the final frontier of human existence at the moment, to try to understand the brain and do it in a non-invasive way.”
Author: Tom Ziemer