Keys to the Mind

ANYONE WHO STEREOTYPES video gaming as the pastime of slackers might be surprised by how Princeton professor David Tank and his research team delve into the neuroscience of navigation. Two floors below the entrance to the new Princeton Neuroscience Institute (PNI) building, behind a heavy black curtain, lies a virtual-reality game fit for a mouse. During a typical experiment, researchers project a maze, similar to what appears in 1990s-era video games, onto a small curved screen. The mouse, alone in its very own IMAX theater, becomes the star of the game, navigating the moving maze by scuttling on a Styrofoam sphere about the size of a bowling ball. As the mouse turns every which way, the ball follows, while the animal’s brain is viewed using a specialized microscope.

he microscope zeroes in on specific groups of cells. A favorite target is a type of neuron in the hippocampus region of the mouse’s brain that fires when the animal is in a particular location in its environment. The readout appears on a nearby computer screen: a flurry of small white circles, each a single nerve cell, lighting up and going dim, each to the beat of its own drum. Now, for Tank’s team, comes the fun part: translating the dynamic patterns of nerve-cell firing into the mouse’s sense of place as it moves through the maze. Full Story.

PNI co-directors David Tank, left, and Jonathan CohenPNI co-directors David Tank, left, and Jonathan Cohen. {credit: Peter Murphy}