A modified version of Quake 2 has helped scientists dramatically improve their ability to study neurological activity in the brains of moving animals.
“One of the major research areas of neuroscience is the development of techniques to study the brain at cellular resolution. The information of the nervous system is contained in the activity of individual neurons,” explained Princeton neuroscientist David Tank. Unfortunately, studying those individual neurons has thus far only been possible in cell cultures, not in the “real, living brains” of moving animals.
“The neurons move back and forth while you’re trying to measure things,” Tank continued. “So we developed a way to keep the head fixed in space, but still have mice perform behaviors that are usually studied in mice running through a maze.”
The system is actually quite simple: A fixed metal helmet holds the mouse in place atop a large styrofoam ball supported by a jet of air; sensors taken from optical mice surround the ball and measure its movements as the mouse runs through a virtual maze generated by a modified version of the Quake 2 engine. A glass capillary (that’s like a thin tube, Einstein) only one micron wide and filled with salt water is inserted into the hippocampus of the mouse, where it can detect electrical currents as they pass through individual cells.
Tank said that the results generated so far will only be of interest to neuroscientists and that “more work is needed to nail this down.” But cognitive scientist Douglas Nitz of the University of California at San Diego was a bit more excited about it. “It is difficult to overstate the importance of understanding how the dynamics of electrical activity within single neurons is related to firing patterns among collections of neurons that accompany the performance of complex tasks,” he said.
Okay, so maybe it is only of interest to neuroscientists at this point. It’s still pretty damn cool.