Neuroethology of releasing mechanisms: Prey-catching in toads

@article{Ewert1987NeuroethologyOR,
  title={Neuroethology of releasing mechanisms: Prey-catching in toads},
  author={J. -P. Ewert},
  journal={Behavioral and Brain Sciences},
  year={1987},
  volume={10},
  pages={337 - 368}
}
  • J. Ewert
  • Published 1 September 1987
  • Biology
  • Behavioral and Brain Sciences
Abstract “Sign stimuli” elicit specific patterns of behavior when an organism's motivation is appropriate. In the toad, visually released prey-catching involves orienting toward the prey, approaching, fixating, and snapping. For these action patterns to be selected and released, the prey must be recognized and localized in space. Toads discriminate prey from nonprey by certain spatiotemporal stimulus features. The stimulus-response relations are mediated by innate releasing mechanisms (RMs… 

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References

SHOWING 1-10 OF 231 REFERENCES

Snapping in Toads: Some Aspects of Sensorimotor Interfacing and Motor Pattern Generation

It was reasoned that, if the neuronal traffic associated with this motor component was followed “upstream” it should eventually reach neuronal substrates that already had been explored from the sensory side and implicated to play a role in visually guided prey-capture.

Concepts in vertebrate neuroethology

  • J. Ewert
  • Biology, Psychology
    Animal Behaviour
  • 1985

Is the Mauthner Cell a Vertebrate Command Neuron? A Neuroethological Perspective on an Evolving Concept

The command neuron concept has been particularly influential in neurobiology because it provides a mechanism to explain how behavior patterns might be triggered by particular combinations of stimuli.

Focal attention in the frog: behavioral and physiological correlates.

Results of the present study suggest that self-exciting neural loops within the tectum mediate this type of selective attention in frogs.

Neural correlate of behavioral plasticity in command neurons of Pleurobranchaea.

The results suggest that the command neurons of Pleurobranchaea serve as a neural locus at which an animal's behavior is modulated by past experiences and establish a neural correlate of behavioral plasticity, in the form of synaptic inhibition of thecommand neurons.

The Jamming Avoidance Response in an Electric Fish: Algorithms in Sensory Information Processing and their Neuronal Realization

The electrosensory system of South American (gymnotiform) and African (mormyriform) electric fish has become a favorite model system to study the integration of sensory information and the resulting
...