Imagine you have been tearing up the dance floor at a wedding, but now dinner is being served and you need to return to your seat — how do you find your table? Your first step will be to determine your heading, or the direction you need to move in. You could do this by locating a feature, like the red centerpiece on your table, or based on the geometry of the room, like the fact that your table was in a corner.
The use of feature vs. geometric cues in orientation and navigation has been of great interest in comparative and animal psychology. However, because "geometric cues" typically refer to the shape of a space, research in this area has typically focused on horizontal spatial orientation cues (e.g., wall length). Nonetheless, there is evidence that some animals, like fish and hummingbirds, make use of vertical spatial cues, likely because flying and swimming involve navigation in three-dimensional volumetric space.
Pigeons represent a particularly interesting test case, because although they fly and therefore have experience with vertical movement, unlike hummingbirds they typically forage for food while walking on the ground, and so have more experience orienting to rewards on a horizontal plane.
In a recent paper published in Journal of Experimental Psychology: Animal Learning and Cognition, Du, Mahdi, Paul, and Spetch (2016) (PDF, 144KB)opens in new window tested the use of vertical orienting cues in pigeons. Pigeons were trained to locate goal food containers in diagonal corners of a rectangular space. Because the space was rectangular, wall length served as a horizontal cue. In addition, the two walls that were shorter in length were also shorter in height, thus providing a vertical cue.
Pigeons were then tested in spaces that either contained only horizontal cues (rectangular space where all walls were the same height), only vertical cues (square space where walls varied in height as during training), or where horizontal and vertical cues were in conflict (rectangular space where, in contrast to training, the walls that were shorter in height were longer in length).
Pigeons located the goal containers significantly more often than chance when only horizontal cues were present, but not when only vertical cues were present. Furthermore, when horizontal and vertical cues were in conflict, pigeons were more likely to choose containers in corners indicated by the horizontal cues.
However, when all walls were shorter so that the difference between short and tall walls was more easily visible to birds standing on the ground, this advantage for horizontal cues disappeared: pigeons were equally successful when only horizontal or only vertical cues were presented.
Moreover, when both cue types were presented in conflict, four of the six pigeons tested showed a preference for vertical cues.
Thus, pigeons are able to orient using both horizontal and vertical cues. These results suggest that horizontal and vertical spatial information are not differentially represented in the brain, as suggested by studies on head direction cells and grid cells in rats, but rather that the priority given to horizontal versus vertical information depends on salience.
Citation:
- Du, Y., Mahdi, N., Paul, B., & Spetch, M. L. (2016). Cue salience influences the use of height cues in reorientation in pigeons (Columba livia). Journal of Experimental Psychology: Animal Learning and Cognition, 42(3), 273–280. https://dx.doi.org/10.1037/xan0000106
Note: This article is in the Basic / Experimental Psychology topic area. View more articles in the Basic / Experimental Psychology topic area.