Could Interactions Between Brain Regions Cause Schizophrenia?

In the middle of a conversation with his mom, he glimpsed the figure of a man from the corner of his eye.

But when he turned his head, the figure was gone.

Minutes later, the figure appeared again in his peripheral vision, creating a debilitating sense of concern.

Still, no man was present.

It’s the exact type of visual hallucination some 3 million schizophrenia patients experience.

Scientists don’t know exactly what causes the condition, but a new project led by University of Minnesota Medical School researcher Scott Sponheim, Ph.D., will explore why these episodes of visual distortion occur, potentially leading to improved treatments.

Schizophrenia patients often have difficulty with low-level functions such as basic processing of visual stimuli. They can also have compromised high-level brain functions like attention and memory. So Sponheim will analyze the interaction between the visual cortex and the prefrontal cortex where these low- and high-level functions take place to determine how connected brain regions generate visual distortions.

“Over the past decade, researchers have made huge advances when it comes to mapping connections in the brain,” Sponheim said. “Now we have to understand how alterations in the connections from one part of the brain to other brain regions might explain brain disorders such as schizophrenia.”

Funded by a $3 million grant from the National Institutes of Mental Health, Sponheim will partner with the university’s Center for Magnetic Resonance Researchto obtain highly detailed brain images of 150 schizophrenia patients while they perform tasks that prompt activity in the visual and prefrontal cortexes. He’ll also scan the brains of 100 people who are immediate relatives to schizophrenia patients and 50 healthy people who are not related to schizophrenia patients. This data will then be added to the Human Connectome Project repository, serving as a reference for future research.

These images could help researchers better understand healthy brain networks and identify how brain connections may lead to the development of schizophrenia.

Sponheim expects that people with schizophrenia will have abnormal activity in both the prefrontal and visual cortex, while healthy relatives who carry genetic vulnerability for the disorder will only have abnormal activity in prefrontal areas. He thinks the interplay between both abnormalities in the brain causes the hallucinations and represents problems with brain connections that result in schizophrenia.

“By identifying mechanisms for the hallucinations, we can eventually develop more targeted treatments that might improve compromised portions of the brain and improve brain health,” he said. “This research may also point to ways of identifying whether a person could be on the path to developing schizophrenia, so that we can intervene earlier. We hope it’ll be an important building block for mental health research and treatment.”