Princeton Researchers Discover Mysterious Region of the Brain That Acts Like a Switchboard Operator

Posted on August 20, 2012

Brain Pulvinar Switchboard Operator


Researchers from Princeton University say they have discovered a mysterious region deep in the human brain that could be where we sort through incoming stimuli from the outside world and focus on the information currently most important to our behavior and survival. The researchers say an area of our brain, called the pulvinar, regulates communication between clusters of brain cells as our brain focuses on the people and objects that need our attention. The scan above shows the pulvinar communicating with the occipital lobe (yellow) and the temporal lobe (red) individually, and with both (green).

The researchers say this region of the brain acts like a switchboard operator. Without guidance from the pulvinar, an important observation such as noticing an oncoming bus as you are crossing the street could get lost in a jumble of other stimuli.

The researchers developed a new technique to trace direct communication between clusters of neurons in the visual cortex and the pulvinar. The team produced neural connection maps using an MRI and then placed electrodes along those identified communication paths to monitor brain signals of macaques. The researchers trained the monkeys to play a video game during which they used visual cues to find a specific shape surrounded by distracting information. As the macaques focused, the researchers could see that the pulvinar controlled which parts of the visual cortex sent and received signals.

Yuri Saalmann, an associate research scholar in the Princeton Neuroscience Institute (PNI), explained the interesting findings in a release. Saalman says, "Our study suggests that a mysterious area in the center of the brain called the pulvinar acts as a switchboard operator between areas on the brain's surface known as the visual cortex, which processes visual information. When we pay attention to important visual information, the pulvinar makes sure that information passing between clusters of neurons is consistent and relevant to our behavior."

The research was published here in the journal Science.

Photo: Image courtesy of Science/AAAS