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The movements of rats trained to reach through an aperture for food pellets, located on a shelf, were videorecorded and filmed from lateral and ventral perspectives for analysis using Eshkol-Wachman Movement Notation (EWMN). Reaching was subdivided into phases of locating the food and advancing the limb to grasp the food, bringing the food to the mouth, and returning to the starting position. Further analysis of the movements comprising these acts revealed a number of novel findings. (1) Most of the first phase of the movement is produced proximally, with the limb lifted, aimed, and advanced from the shoulder. (2) After the limb is lifted from the substrate to initiate reaching, it is carried to a parasagittal position so that the long axis of the forearm is aligned along the midline of the body. This aspect of the movement 'aims' the limb toward the target. (3) The digits are opened as the limb is advanced from the aiming position toward the food. As the paw approaches the food, pronation of the palm is accomplished by abduction of the upper arm. (4) As the limb is retracted, the digits are closed to grasp the food. As retraction ends, the paw is supinated by a rotatory movement at the wrist. This is the only distal rotatory movement. (5) The position taken by the second forelimb, as it is adducted to aid in holding the food pellet for eating, resembles the 'aiming' posture. The results are discussed in reference to the kinematics, neural control, and the evolutionary origins of reaching in the rat and other animals. Additionally, the results provide a framework for analysis of changes in movements produced by physiological manipulations.

Rodger and Rosebrugh (1979) developed a method for identifying sets of rules by which discrete responses are combined to form functional sequences of behavior. In the present study, this so-called finite-state behavioral grammar method was used to analyze the food-hoarding behavior of Syrian golden hamsters (Mesocricetus auratus). Specifically, it was used to analyze 127 videotaped food-hoarding sequences that were observed in 14 male, adult hamsters in an apparatus that comprised a home compartment, a foraging area, and a connecting tunnel. An integral part of grammar derivation is the development of hypotheses about the function of the observed response patterns to guide the grammar derivation. Two such hypotheses guided the present analysis: first, we hypothesized that behaviors observed in the foraging area after the hamsters' cheek pouches were filled served an exploratory function; second, we hypothesized that behaviors observed in the home compartment prior to the hamsters emptying their cheeck pouches served to assess potential food deposition sites. In addition to generating these two hypotheses and the grammars for the hoarding sequences, this study demonstrates how the finite-state grammar method can be used as a productive means of gaining insights into the organization of consummatory response sequences.