Heading in the rat: Determination by environmental shape

Abstract

After a 75-sec intratrial delay, rats that had been shown the location of hidden food within a rectangular box correctly dug at that location in a second identical box, which had been moved into the same position within the room. For some rats, the opposing ends of the boxes were differentiated by distinctive comer panels; for others, there were no panels. When, during the delay interval, the turntable supporting both boxes was rotated by more than 180 0 , 80 that the second box no longer took the place of the first box within the room, the rats showed performance decrements. Nevertheless, 4 subjects selected the correct location significantly more often than the rotationally equivalent location, which corresponds to the correct location when the ends of the box are confused. The amount of rotation had no significant effect for any rat. In a final phase, the rats were denied perceptual access to cues outside the test box, which now had differentiating comer panels for all rats. Despite the distinctive panels, no rat showed a significant difference between correct digs and rotational errors; that is, no rat reliably distinguished one end ofthe box from the other. Results confirm previous findings that rats rely primarily on environmental shape to establish their heading. They ignore distinctive features of the surfaces that define environmental shape, even when the shape by itself is insufficient to establish a unique orientation.Recent experiments have strengthened the longstanding hypothesis that diverse animals form cognitive maps, behaviorally useful records of the geometric relationships among points in the environment (Gould, 1986;Tolman, 1948). Animals commonly orient toward points that are specified not by their intrinsic sensory/perceptual characteristics but rather by their remembered location within the spatial framework defined by surrounding objects (Tinbergen & Kruyt, 1938;Tinklepaugh, 1932; see Gallistel, 1989, for review of recent literature). This form of animal orientation is sometimes called piloting, by analogy to the orienting of mariners with respect to a hidden shoal on the basis of the shoal's remembered (charted) location relative to observable shore points. The experiments of Morris (1981) with rats in a water maze make this analogy particularly apt: The rats were to find a brick just beneath the surface of opacified water. The hidden brick itself had no distinctive features; thus, it had to be found by virtue of its position within the known space (the swimming pool and the experimental room).Establishing one's position and orientation (heading) within the framework established by the known (mapped) aspects of the environment is fundamental to piloting. There is extensive experimental evidence that extramaze, or "room," cues are important determinants of the rat's orientation within a maze (Carr, 1917; Hebb, 1938;Olton & Samuelson, 1976;Ritchie, 1947;Suzuki, Augerinos, & Black, 1980), but what constitutes the behaviorally imRequests for reprints may be addressed to C. R. Gallistel, Depa...

Evidence of blocking with geometric cues in a virtual watermaze

“…The pre-exposed geometric cue of the platform array in Experiment 2 did not disrupt learning about the position of the platform in terms of the non-geometric red wall. Similar lack of interaction between geometric and non-geometric cues has been found (e.g., Redhead & Hamilton, 2007) and taken as evidence that geometric cues are impervious to disruption by other types of cues (e.g., Cheng, 1986;Gallistel, 1990;Margules & Gallistel, 1988;Wang & Spelke, 2002).…”

Is there a geometric module for spatial orientation? Insights from a rodent navigation model.

“…A particularly striking evidence for the control of behavior by configural cues has been observed during reorientation experiments in rectangular arenas (Cheng, 1986;Hermer & Spelke, 1996;Margules & Gallistel, 1988). In a typical experiment, a food-deprived animal is shown the location of a food source in a rectangular arena with distinct landmarks in the corners (Cheng, 1986).…”

Place recognition and heading retrieval are mediated by dissociable cognitive systems in mice

“…This pattern of behavior indicates that the animal is using geometry as a cue, because these two corners have the same spatial relationship to the chamber geometry. The animals will often ignore other orienting cues such as odors, visual patterns, and wall color, even when these cues provide polarizing information that could potentially resolve the geometric ambiguity (6,8). Although the exclusive reliance on geometric cues is not found under all circumstances (9, 10), it has been observed in a large number of studies.…”