Finding the answers to commonly asked questions about the way humans think is no easy task. But Arka Mallela, MD, MS, assistant professor, Department of Neurological Surgery, knows the more clinicians learn about the brain, the better they can take care of patients.
Mallela spent much of his early career in Pennsylvania where he earned his medical degree and completed his residency. He had a clear idea of what he wanted in his next move, and Rush checked all his boxes.
“I came to Rush because I was looking for a place that took excellent care of patients, had a busy epilepsy practice and had an epileptology program that was willing to invest in brain mapping and surgical epilepsy,” Mallela says. “It’s a team sport, so you really need the neurology department to be on board, and Rush has great people in neurophysiology.”
Mallela joined Rush’s faculty team in August of 2025, and his work is unique. Part of it includes operating a clinic as an epilepsy and brain tumor surgeon. The other involves running a brain mapping lab that can answer questions about how we process and form language.
What is brain mapping?
Brain mapping is a combination of imaging, recording of brain activity, electrical stimulation and behavioral testing to understand where important functions are in the brain and how they can be preserved or carefully worked around during procedures. Mallela says, in short, it’s a tool to better treat patients.
“Brain mapping helps us understand how patients’ brains work and how their pathologies, epilepsy or tumors affect those functions,” he says. “It’s also a scientific tool because it helps us understand how function is represented in the brain. For instance, how does a thought become a word? And how does a word become something we actually speak out loud?”
While brain mapping helps researchers make sense of language, it also has serious impacts on patients with brain tumors or epilepsy.
A 'lay of the land' leads to better patient care
Brain mapping is most relevant for tumors like glioma and glioblastoma that start in and infiltrate the brain. In scenarios like this, brain mapping is almost exactly what it sounds like.
“We use a combination of behavioral testing and imaging to understand a rough lay of the land and where the patient is starting from,” Mallela says. “Then, in surgery, we actually use electrical stimulation and other techniques to map the differences between the functioning brain and where the tumor is.”
Mallela says it’s important for neurosurgeons to understand where important functions are in the brain so they can preserve those areas. That’s because taking out as much tissue as they safely can is the No. 1 way to treat and potentially cure those tumors.
Brain mapping for epilepsy is similar to brain mapping for tumors. Surgeons first use behavioral testing, noninvasive brain recording and imaging. For certain patients, recording from inside the brain with stereo EEG — a minimally invasive procedure that maps seizures — is another tool.
"Often with those kinds of efforts, we can surgically remove the parts of the brain that are causing epilepsy while minimizing the cognitive deficits,” Mallela says. “In cases where we can’t do that, we have access to neuromodulation, where we don’t remove any networks in the brain, but we use electrical stimulation to change how those networks function.”
Brain mapping is also helping researchers get a better understanding of what networks in the brain support psychiatric disorders like obsessive compulsive disorder, anxiety and depression. Mallela says brain mapping helps them improve noninvasive and medical treatments for patients with these disorders.
Setting big goals to answer big questions
Mallela’s research is fueled by his passion, his team of epileptologists and neuropsychologists, and funding from Rush. He says there has been significant progress in the brain mapping center, and it continues to grow.
His goal is to become even more ambitious. To Mallela, that means making the Rush Center for Brain Mapping the premiere institution in Chicago for surgical brain mapping.
“We proposed the Rush Center for Brain Mapping, and it was approved last fall. Now, we’re making it visible and letting people in Chicago know that Rush is good at this, and it’s something we do regularly,” he says. “We’re happy to take care of patients with complex problems.”
Mallela says Rush is advancing the understanding of the human brain and answering the questions we’ve asked ourselves through all of human history.
“How do we think? Where does thought come from? How do we remember things?” Mallela asks. “These questions tickle people’s curiosity. Not only is this going to help patients enormously, but it’s going to answer some fundamental questions about what makes us human.”
