XXII. Read Text B. Translate it. State the difference between conditioned and unconditioned reflexes: Text B. Conditioned Reflexes All the visceral and somatic reflexes including the protective, feeding and others are formed by various internal and external stimuli. These stimuli produce reactions not depending on surrounding conditions. The great Russian physiologist Pavlov called them unconditioned reflexes. In human beings the nervous system has the additional ability to form cortical associations which increase the range of reactions. This function is obtained by all the human beings and formed upon signalization, i.e. the process in which an ineffective reflex stimulus forms the same reactions as the stimulus with which it has become associated. Pavlov called these individually obtained reflexes conditioned, because they are developed only in connection with some other reflexes. It is through constant contacts of life that men develop many conditioned reflexes. They begin to develop already in infancy. During human development their number is much increased through training and education. In experimental conditions it was determined by Pavlov that many new conditioned reflexes to stimuli not supplied by Nature could be established in dogs. But such stimuli had to be associated with those which formed an unconditioned response. Pavlov determined that in higher animals it was in the cortex that conditioned reflexes were formed.

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