Influence of the background for discriminating object motion from self-induced motion in toadsBufo bufo (L.)
- Cite this article as:
- Burghagen, H. & Ewert, J.P. J. Comp. Physiol. (1983) 152: 241. doi:10.1007/BF00611188
- 49 Downloads
Prey-catching behavior of common toads can be elicited by moving retinal images of appropriate size and configuration. In this evaluation, both stimulus and background features are taken into account. Moving retinal images may occur in different stimulus situations: (i) a small object traverses a part of the toad's visual field while the animal itself is sitting still; (ii) the toad approaches or passes a stationary small object during walking; (iii) the toad is passively moved in front of a small stationary object.
Toads respond in situations (i)-(iii) with prey-capture providing the retinal image (stimulus) is prey-like and the surrounding background is homogeneous. If a prey object is presented in front of a textured background, toads respond well in situation (i), whereas in situations (ii) and (iii) the probability of prey-catching responses is very low. It is concluded that, in the biotope, the textured background plays a decisive role in the discrimination between object motion and self-induced motion. The underlying neurophysiological mechanisms are discussed.