Factors in two-dimensional maze navigation by pigeons.

摘要

Navigation of two-dimensional mazes in a computerized environment has been used to assess and compare spatial cognition in human and nonhuman primates. Recent technology advances have led to the extension of these maze tasks to pigeons. To determine the extent to which the joystick and touch screen technologies can be used to compare these species, the effect of various manipulations on the touch screen task should be accomplished and the results compared to those of the primate literature. If the sources of control for each task are not equated across species, possible quantitative differences (i.e., level of a process) may by explained as qualitative differences (i.e., absence of process). The overall goal of these studies was to assess stimulus control by various maze parameters inherent in two-dimensional maze navigation. The first experiment assessed how two types of choice points (i.e., forced and facultative) affected performance. The results indicate full transfer (i.e., maze navigation) after training with facultative-choice mazes, and partial transfer after training with forced-choice mazes. Experiment 2 addressed the effect of proximal but unavailable paths on performance. The results indicate that at a short distance to the goal, control by path characteristics (i.e., wall) decreases. Expanding on the implications of distance, Experiment 3 assessed distance discrimination in both simple and complex (i.e., curved) paths. The results indicate that the distance to the goal affects responses when the difference in distance between two paths is large. Experiment 4 expanded the analysis on path complexity by comparing performance across various ratios of directional changes within a path while holding the Manhattan (i.e., actual path distance to the goal) and Euclidean (i.e., shortest path to the goal assuming no limitation in direction) distances constant. The results indicate that path complexity does not affect performance. The results suggest that under certain manipulations the pigeons may reach the same levels of path-planning as primates. However, the analyses also suggest that higher levels of planning may require redefining in order to account for sources of behavioral control.