Analysis of skilled forelimb movement in rats: the single pellet reaching test and staircase test

Brain damage, stroke, and neurodegenerative diseases such as Parkinson's or Huntington's disease can cause severe motor deficits in skilled forelimb use in both humans and rats. These deficits are typically analyzed in a reach-to-eat paradigm. Skilled reaching in rats has been found to be a good model of human skilled reaching. Therefore, rats serve as an excellent tool to monitor the development of deficits after neurological insults or changes after medical intervention. The following protocols comprise two different tests of rat skilled reaching. The single pellet reaching test is a paradigm that involves detailed rating and analysis of qualitative aspects of the reaching movement itself. The staircase test is an objective, high-throughput reaching task that allows reaching success (number of pellets eaten) to be investigated in multiple rats at the same time. Both tests have been used extensively to investigate motor deficits and effects of treatment.