Research indicates mice respond similarly to stimuli in virtual and real environments
Whether venturing through distant galaxies or traversing fantasy realms, virtual reality has transported humans to extraordinary locations. Now, mice can partake in this immersive experience, thanks to researchers who have created virtual reality “goggles.” These devices immerse rodents in diverse scenarios, such as navigating mazes or facing potential predators. While virtual reality has been utilized in mouse experiments for years, previous methods involved placing mice on a treadmill in front of a large screen, with their heads fixed, limiting their natural movements for brain study.
Professor Daniel Dombeck, a study co-author from Northwestern University in Illinois, highlighted the limitations of previous methods. Mice, while moving on a treadmill in a virtual world, could still perceive the static laboratory surroundings and equipment. According to him, this compromised their immersion in the virtual experience. He explained, “Also, there is no depth information provided by big screens; the mice just see the same flat scene as we do when we watch TV.”
In contrast, the newly introduced setup, outlined in the journal Neuron, features a pair of lenses and screens positioned on stands on either side of a mouse’s head. This configuration provides each eye with a 180-degree field of view. Despite the mouse’s head being fixed, it can explore the virtual environment using the treadmill.
Our current goggle system, as outlined in this paper, is somewhat bulky for mice to carry. However, we aim to develop smaller versions in the future that mice can wear like a headset,” stated Dombeck.
The team emphasizes that their innovative approach not only enables mice to perceive the virtual environment in 3D and removes visual cues from the lab but also provides a means to present virtual images from an aerial perspective, such as that of a hovering hawk.
The stimulation in natural settings induces mice to either freeze or flee, behaviors essential for their survival in the wild during a predatory bird attack,” explained Dombeck.
The team’s trials reveal that mice exhibit similar reactions within the VR goggle system. When the mice froze, neural activity in their brain regions associated with navigation indicated a perception of a location different from their actual surroundings.
It was as if they were contemplating a preferable destination—a secure, sheltered spot up ahead,” remarked Dombeck. He added that such findings might contribute to understanding the origins of imagination in the brain.
The team is actively investigating the identification of neurons responsible for memory formation during mouse maze navigation. They are also exploring the modifications occurring in the connections between these neurons that contribute to memory formation and decay.
Addressing these questions will enhance our comprehension of how our brains ascertain our location in the surrounding world, the process of forming memories from those experiences, and, ultimately,” stated Dombeck, “the mechanisms underlying the degradation of these memories in neurodegenerative diseases.
