Learning and Memory in the Toad’s Prey/Predator Recognition System: A Neural Model

  • Rolando Lara


A neural model of the mechanisms responsible for learning in the prey/predator recognition system of the toad is proposed. The prey/predator recognition system consists of retina-tectum-thalamus-pretectum interactions. This system is modulated by a group of (telencephalic and thalamic) neurons which can change the inhibitory effect of pretectal neurons on tectal cells as a result of experience. The model can simulate the following phenomena: (1) Long-term stimulus-specific habituation; (2) learning to avoid bees; (3) learning not to avoid, and even to snap at, predator-like stimuli; (4) learning to discriminate between palatable and unpalatable stimuli based on color cues. All these changes are produced not as a consequence of change in the transmission of information across subsequently connected neurons, but as a change in the dynamics of a whole network. Learning in our model is exhibited as the capacity of the system to choose for a specific situation the proper motor pattern rather than as the mere storage of information. Learning in this sense can be regarded as the dynamic changes of the system that allow the animal to shift from one to another motor schema or to assign different perceptual schemas to the same motor schema.


Neural Model Motor Schema Bufo Bufo Perceptual Schema Tectal Neuron 
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Copyright information

© Springer Science+Business Media New York 1989

Authors and Affiliations

  • Rolando Lara
    • 1
  1. 1.Centro de Investigaciones en Fisiologia CelularUniversidad Nacional Autonoma de MéxicoMéxicoMéxico

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