A new virtual reality system allows researchers to control what a freely moving fly sees and study how it responds to its environment. (See full video.)STRAWLAB.ORG/FREEMOVRFlies, fish, and mice can now enter virtual reality (VR) without being tied down. European researchers have developed a set-up for freely moving animals that may offer more detailed insight into how animals’ brains work in social situations. They describe the system today (August 21) in Nature Methods.
“The fundamental challenge with experiments on social behavior is that it is difficult to control interactions between real animals,” Andrew Straw of the University of Freiburg in Germany tells The Scientist by email. “With virtual reality in unrestrained animals, the interaction can be with one or more ‘animals,’ which are in fact images controlled precisely by a computer program.”
Straw says VR experiments in tethered animals have been incredibly useful in studying social behavior. But past studies have shown that restraining the animals can yield misleading results. For example, a 2013 study published in Science showed that in restrained-animal VR, fewer hippocampal place cells fire compared to freely moving animals.
IMP/IMBA GRAPHICS DEPARTMENT, STRAWLAB.ORG/FREEMOVR“The visual VR we developed allows us to perform highly controlled visual experiments while the locomotor control system is operating completely normally,” Straw says. “This is particularly important for studies on spatial cognition, where it is clear that animals use external sensory cues when available, such as visible landmarks, and internal cues, such as distance walked.”