High-Speed Video Recording Used for the Analysis of Hand Shaping in Overground Walking, Cylinder Exploration, Skilled Reaching, and Rung Walking in Ra

Hand shaping in the rat (Rattus norvegicus ) is adapted to many functions, including walking, climbing, exploration, and skilled manipulation. An understanding of hand movement can provide insights into the neural control of movement and the impairments that result from brain injury. Here, hand movements are described in a number of widely used tests: overground walking, horizontal or inclined ladder rung walking, exploring a vertical wall of a cylinder, and skilled reaching for food. High-speed (250–1,000 frames/s) video recording with frame-by-frame behavioral and kinematic analyses reveals the details of hand shaping and its sensory control. Three hand gestures are common to all tasks: (1) release—the hand is pushed off and lifted from a substrate; (2) collection—the digits are closed and flexed through limb transport; and (3) manipulation—the hand and digits are shaped to contact a target. Manipulation features specialized digit use and varied sensory control (olfaction, vibrissae and sinus hairs, and tactile senses) in the different tasks. Conserved release and collection vs. the variability of manipulation reveal the multisensory skilled action used in control of the hand.