Stimulus control and function of arm and wall travel by rats on a radial arm floor maze

Hoffman, Timberlake, Leffel, and Gont (1999) concluded that the tactic of effective trail following (in the form of arm and wall travel), rather than distance minimizing, central-place search, or random search, best characterized the locomotion of rats on a radial arm maze placed flat on the floor of an arena (a floor RAM). The present experiments analyzed further the stimulus control and function of arm and wall travel. Experiment 1 showed that arm travel was controlled more by the edge of a maze arm than by its surface. Experiment 2 showed that rats with whiskers clipped on one side traveled along arms less and along walls more than did intact rats. Experiment 3 showed that maze arms increased search effectiveness and decreased suppression of locomotion by bright light and a novel environment. The results support the hypothesis that arm and wall travel are based on mechanisms of trail following, which, in natural settings, contribute to food finding and regulation of social relations and fear.