(A) Illustration of the restraint setup used to train and to image marmosets. The animal wears a sleeveless jacket which is attached to a plastic back cover. The back cover is fastened to the sidebars on the cradle, preventing the animal from sliding out. At all times, the arms, legs, and tail of the animal are free to move. The head of the marmoset is secured by a two-piece, custom-built helmet made specifically for that individual. The chin piece on the bottom supports the chin of the animal, and the head piece on the top prevents head motion. Both helmet pieces are lined up with foam on the inside to provide a comfortable support to the entire head. The animal sits in the sphinx position looking out towards the back of the magnet. The bed is secured to the bed sliding mechanism on one end via the hanger.