It consisted of a 100-electrode panel about the size of a baby aspirin that was placed on the surface of the brain at a fold in the motor cortex where hand movement is controlled.
Handmade from the tough bark of the Tara Wing-Celtis or Blue Sandalwood tree and rice straw, Xuan paper is known for its strong, smooth surface, its ability to absorb water and moisten ink, and fold repeatedly without breaking.