Human brain creates a universal code to track movement: study

With the COVID-19 outbreak, the world has learned to cope up with the new normal of social distancing. Following this trend, a group of researchers at the University of California, Los Angeles (UCLA) have studied how a human brain navigates places and monitors someone else in the same location.

The senior author Nanthia Suthana, the Ruth and Raymond Stotter Chair in Neurosurgery and an assistant professor of neurosurgery and psychiatry at the David Geffen School of Medicine at UCLA and Jane and Terry Semel Institute for Neuroscience and Human Behavior states that “we studied how our brain reacts when we navigate a physical space first alone and then with others.”

The findings of the research reveals that human brains create a universal code to locate other people in relation to them, added Suthana, whose laboratory studies how the brain forms and recalls memories.

The research was conducted by observing epilepsy patients whose brains had been surgically implanted earlier with electrodes to control their seizures. The electrodes are placed in the medial temporal lobe which is the part of the brain linked to memory and regulates navigation, similar to a GPS device.

“Earlier studies have shown that low-frequency brain waves by neurons in the medial temporal lobe help rodents keep track of where they are as they navigate a new place. We wanted to investigate this idea in people and test whether they could also monitor others near them but were hampered by existing technology,” said first author Matthias Stangl, a postdoctoral scholar in Suthana’s lab. 

Suthana’s lab developed a special backpack with a computer that wirelessly connects to brain electrodes. This allowed researchers to study the participants’ brain signals as they moved freely instead of the traditional method where they have to lie still in a brain scanner or hook up to recording devices.

During the experiment, each participant was instructed to carry the backpack and to explore an empty room, find a hidden spot and remember it. While they walked, the backpack recorded their brain waves, eye movements and paths through the room in real-time.

As the participants searched the room, their brain waves flowed in a distinctive pattern, suggesting that each person’s brain had mapped out the walls and other boundaries. Interestingly, the patients’ brain waves moved in a similar pattern when they sat in a corner of the room and watched someone else approach the location of the hidden spot. The finding shows that every human brain generates the same pattern to track the people in a shared environment.

In a secondary finding, the research team found that what a person pay attention to may influence how their brains map out a location. For example, the patients’ brain waves flowed stronger when they searched for the hidden spot or witnessed another person approach the location than when they simply explored the room.

“Our results support the idea that, under certain mental states, this pattern of brain waves may help us recognize boundaries. In this case, it was when people were focused on a goal and hunting for something,” said Stangl. 

The studies will further explore the pattern of human brain reactions in more complex social situations like outside the laboratory. The UCLA team is working to make the backpack available to other researchers to accelerate discoveries about the brain and brain disorders. The study was supported with funding from the National Institute of Health’s Brain Initiative, McKnight Foundation and Keck Foundation.