In a recent study, researchers discovered the existence of two distinct maps in the brain’s secondary motor cortex. The research offers a transformative look at how the brain controls spatial planning and navigation. This dual map—one ego-centered, the other world-centered—provides vital insight into how our brains manage complex tasks, from planning movements to understanding our position in the environment.

This remarkable discovery could have far-reaching implications for understanding a variety of neurological conditions, such as stroke, that impair spatial attention and the ability to navigate one’s environment. The research opens new avenues for targeted treatments that could speed recovery and improve the quality of life for patients with these diseases.

Binary maps in the brain

“We found that the premotor cortex uses an egocentric coordinate system for spatial planning, but also encodes a world-oriented map that is used to determine the body’s current position in the world,” said Dr Jeffrey Ehrlich, leader of the team at the Sainsbury’s Wellcome Centre at UCL.

“This egocentric and world-centric information is combined in a multiplicative way in individual neurons, making it easy to decode.”

A published study Journal of Neurosciencepresents a new task that allows researchers to distinguish between egocentric and world-centered reference frames using machine learning techniques. To decipher this information, the experts recorded the neural activity of the anterior orienting area (FOF), a part of the secondary motor cortex, in rats.

How does the brain switch between maps?

“Imagine being asked where the nearest coffee shop is. You might say, ‘Go forward and turn left’ (egocentric direction) or ‘go north and then go east’ (earthcentric direction),” Dr. Ehrlich said.

“We want to understand how the brain switches between these reference frames and translates them into action.”

The task involved carefully training mice to insert their noses into a designated starting hole, after which a light indicating the target hole was illuminated. This setup required the mice to focus on a visual cue as a guide for their next movement, improving their understanding of spatial location.

Following the auditory cue, the mice moved toward the target window to receive the reward, strengthening the association between the cue and their actions. The significant delay between the visual cue and the appearance of the auditory signal allowed the researchers to closely monitor neural activity.

This pause made it possible to distinguish the brain’s planning phase from subsequent actions, and allowed the experts to determine whether the frontal orientation area (FOF) was using an egocentric or world-centric map for spatial planning during the task.

The map is located in the front orientation area

“By adding just the right amount of complexity to our task, we were able to experimentally control the timings well. This approach allowed us to distinguish between different dimensions of representation,” said Dr. Ehrlich. Interestingly, the researchers discovered an earth-centered map in the frontal orientation area, a previously unreported finding.

“We were surprised to discover the world map, which had never been reported before in FOF. We want to investigate what this business information is used for and under what conditions it becomes functionally meaningful,” said Dr. Ehrlich.

Brain maps and spatial attention

Brain maps play a critical role in shaping how we perceive, navigate, and interact with the world. They are essential for motor control, sensory perception, and spatial awareness, which reflect the connections between our bodies and the environment.

The discovery of egocentric and world-centric maps in this study offers new insights into how the brain processes different types of spatial information. These two maps work together to allow the brain to plan movements and navigate space, reflecting the brain’s incredible ability to adapt.

Gaining a deeper understanding of how these maps are created and maintained could provide critical insight into neurological diseases that impair spatial perception. This knowledge could pave the way for new treatments aimed at improving spatial attention and promoting recovery in patients with disorders such as hemispatial neglect.

Wider implications of the study

The research team is currently focusing on investigating how these dual maps work during tasks that involve instructions to the world and how the brain plans more complex sequences of movements.

The findings could have important implications for understanding the relationship between spatial attention and neurological disorders, with the potential to create new treatments for conditions such as stroke. The study was published in the journal JNeurosci.