hat we see often determines how we act: We hit the brakes if a car is stopped ahead of us. We duck to avoid a low-hanging tree branch. We bend down to tie our shoe when the laces come undone.
We rarely give these actions a second thought. But Mriganka Sur, a professor at the Massachusetts Institute of Technology’s Picower Institute for Learning and Memory, is obsessed with them.
“How is vision, which we do effortlessly, transformed into action, which requires volition, which requires attention and engagement?” Sur asked. “How this transformation takes place is a fundamental question that is at the heart of brain function and behavior.”
In a recent mouse study published in Nature Communications, Sur and his team took a step toward answering that question. Their experimental data suggest that the posterior parietal cortex, or PPC, may help us make decisions based on what we see.
First author Gerald Pho, formerly a Ph.D. student in Sur’s lab and now a postdoctoral fellow at Harvard, was exhilarated to see mice’s PPCs light up under a microscope when they made choices based on visual stimuli.
“It’s quite magical,” he said. “It’s almost like fireworks.”
Pho said he’s excited to see how our understanding of visual decision-making will develop as imaging technology becomes more advanced.
“I just think we’re in an exciting time in neuroscience,” he said. “And I think the advance of these technologies can only improve our ability to understand how the brain works in a normal animal, and extending to humans, but also how it goes awry in neurological disease.”