Direct Brain Stimulation Enhances Virtual Reality Experience

Virtual reality has been gaining ground in recent years, and researchers from the University of Washington have presented the possibility of human interaction with virtual reality through direct brain stimulation.

In a study published in Frontiers in Robotics and AI, the researchers shared the first demonstration of humans playing a simple, two-dimensional computer game using only input from direct brain stimulation. This is a very different experience since it does not make use of typical sensory cues from sight, hearing, or touch.

"The way virtual reality is done these days is through displays, headsets, and goggles, but ultimately your brain is what creates your reality," shared senior author Rajesh Rao. A University of Washington professor of Computer Science & Engineering and director of the Center for Sensorimotor Neural Engineering, Rao posed a vital question: "Can the brain make use of artificial information that it's never seen before that is delivered directly to the brain to navigate a virtual world or do useful tasks without other sensory input? And the answer is yes."

While navigating 21 different mazes, subjects had to choose between moving forward or down based on whether they sensed a visual stimulation artifact called a phosphene, which are perceived as blobs or bars of light. To signal which direction to move, the researchers generated a phosphene through transcranial magnetic stimulation, a well-known technique that uses a magnetic coil placed near the skull to directly and noninvasively stimulate a specific area of the brain. When the subjects received the input via direct brain stimulation, the five test subjects made the right moves in the mazes 92 percent of the time. Without guidance, the subjects were only 15 percent correct.

This shows that novel information from artificial sensors or computer-generated virtual worlds can be successfully encoded and delivered noninvasively to the human brain to solve useful tasks through a technology referred to as transcranial magnetic stimulation.

"We look at this as a very small step toward the grander vision of providing rich sensory input to the brain directly and noninvasively," stated Rao. "Over the long term, this could have profound implications for assisting people with sensory deficits while also paving the way for more realistic virtual reality experiences."