According to Northwestern’s Daniel Dombeck, lead author of the study, labs have traditionally used large computers or projection screens to confine an animal. Comparing this to the human experience, he points out that it’s like watching TV in the living room, where cues remind you that you’re not really inside the scene. However, virtual reality glasses, similar to the Oculus Rift, offer a more immersive experience by occupying the entire field of view.
By fixing the mouse on a treadmill, neurobiologists can use tools to view and map the brain as the mouse navigates a virtual space. Dombeck emphasizes that virtual reality essentially replicates real environments.
The team designed a compact headset, called Miniature Rodent Stereo Illumination VR (iMRSIV), with custom lenses and miniature organic light-emitting diode (OLED) displays. With two lenses and screens, one for each side of the head, the system provides 3D vision, immersing the mouse in a 180-degree field of view and excluding the surrounding environment.
By mapping the brains of mice, Dombeck and his team found that mice wearing glasses exhibited brain activation patterns similar to those of freely moving animals. In side-by-side comparisons, mice wearing glasses interacted with scenes more quickly than those wearing traditional virtual reality systems.
Looking ahead, Issa expresses interest in exploring scenarios in which the mouse is the predator rather than the prey. For example, observing brain activity while a mouse chases a fly involves depth perception and distance estimation, aspects the team aims to capture.
Due to their affordability and simplified laboratory requirements, Dombeck anticipates that these glasses could improve the accessibility of neurobiology research.