Pedal press task for skilled hindlimb movements.

<p>Rats were trained to press a floor-mounted pedal with their hindlimb. (<b>A</b>) Schematic of the skilled hindlimb task. (1) After a randomized period of 3–5 seconds, the chime was sounded, cueing (2) the press and release, which, if completed within three seconds of chime onset, led to (3) a water reward. (<b>B</b>) Trace of the position sensor indicating the position of the hindlimb during a single trial of the task (black line). The events chime, start-press, and end-press are marked with circles and the arrows indicate the preparation, initiation and movement windows, as defined in the text. (<b>C</b>) 16 channel stainless steel microwire array with wires of diameter 50 µm, row/column spacing of 350 µm and insulated with Teflon except at the tip. (<b>D</b>) <i>Left Panel:</i> Adapted schematic of the rat cortex showing somatotopic representations <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0052173#pone.0052173-Leergaard1" target="_blank">[56]</a>. Oval indicates target for array implantation in the hindlimb sensorimotor region. <i>Right Panel:</i> Coronal view (schematic) of the rat cortex from Paxinos and Watson 2005, arrows indicating the target for the microelectrodes (<b>E</b>) Four kinematic parameters were measured from the position sensor to describe the behavior of the animal during the task: reaction time, amplitude, peak velocity and duration.