[Conditioned reflex transformation of unconditioned flexion of the limbs of the dog into extension].

In response to electro-skin stimulation of the left forelimb eliciting its flexion,--an escape instrumental reflex was elaborated in five dogs in the form of extension of the stimulated limb (pressure on the support), i.e. a reaction antagonistic to the inborn one. The reaction was elaborated due to conditioned transformation of the unconditioned flexion: the flexion became gradually inhibited and the new form of reaction, previously not inherent in the animal increased and became stable. Such transformation of one reaction into another is connected with the reorganization of inborn coordinations.