When navigating in space, it reveals the human brain to be equally similar spatial-awareness brain waves. The discovery is made after scientists devised a method to scan our brains during free movements, as opposed to lying still in a scanner.
“Our results mean that our brains created a universal signature to put ourselves in someone else’s shoes,” explained neurosurgeon Nanthiya Suthana of the University of California, Los Angeles.
Previous studies in mice have shown that low-frequency brain waves help rodents monitor their position while searching for a new place, defining the boundaries of a place. Similar boundary-defining waves were also identified in humans, but only when they navigated a virtual environment while they were still in place for brain scans.
UCLA neuroscientist Matthias Stangl said, “We want to investigate this idea in people – and also test whether they can monitor others around them.”
So Stangl and colleagues created a mobile brain scanner, made up of a backpack with a computer that connects to implanted electrodes in the brain (a system known as intracranial electroencephalography) to help them study how Our brave forms and spatial memories recall.
Their subjects were five epileptic patients, who had electrodes already implanted in their brains to control their seizures. These implants are contained in the mid-temporal lobe – bits of our brain thought to encode long-term, intentional memories and spatial cognition.
Participants took part in a 15-minute navigation task where they were asked to find and learn the locations of hidden targets within a room. This was followed by a 15-minute observation task, where their participants had to keep track of someone else navigating the room, and press a button when one person crossed the targeted locations.
The researchers observed that as participants approached a physical boundary – such as a room wall – the flow power of low-frequency oscillations in their brain increased. The same happened when they saw someone else approaching the walls.
“We found that boundary-related oscillatory changes were strikingly similar between tasks that require observation of another person’s self-navigation,” he writes in his paper.
Recent studies of mice and bats found the same group of hippocampal neurons code for both the animal’s own location and the location of others of their species.
The power of these brain wave representations of a space, was visualized below, when participants were focused on finding their target location. The oscillation signals were not continuous, and the amount they did not change only their strength.
up: The visualized brainwave strength map of the room boundaries represents the greater amount of power in the brainwave signal.
“Our results support the idea that, under certain mental states, this pattern of brain waves can help us recognize boundaries,” Stangl said. “In this case, it was when people were focused on one goal and hunting for something.”
The electrical activity measured at oscillations within a frequency range is referred to as theta waves. We usually produce these slow but clear waves while navigating, so they are clearly surprised in such a task.
Interestingly, some more buzzy gamma waves also appeared in a similar pattern, with slightly more variation between different conditions. These are the waves we produce to make more use of our brains, drawing experiences into our memories of working.
The team believes that the nerves of the brain they see are generated by multiple groups of neurons that may include cells that encode specifically for borders, objects, and other boundaries and target objects. Better understanding this neuronal language can help us to overcome brain disorders.
And, in an exciting development, he has made his backpack design available to other researchers. Soon, we can expect to know even more about our brain patterns in complex social situations.
His research was published in Nature.