 (iii) Pereira’s third type of movement is produced by training, which certain animals are capable of assimilating. His doctrine is developed through the exposition of specific cases of animal training. For example, Pereira considered the imitation of human language by birds as a special type of reflex mechanism in which hearing organs of birds receive voice waves which are transmitted to a soft area of the brain where they are recorded. When the brain is activated after receiving some stimuli, it causes a series of muscular movements in the speech organs that finally reproduce the previously recorded sounds. In this case, hearing and speech are two sides of a single process. Another case that Pereira studied was that of birds which can emit words that have been spoken in the past. According to him, this is due to the animal memory wherein a voice is retrieved from the corresponding trace or phantasma that is stored in the posterior area of the brain. When these traces are somehow activated, they pass to the anterior zone and provoke the production of the same sounds that created them. But why should an animal emit some words and not others? The explanation is found in the frequency with which a determined voice is presented to the animal: the trace of a frequently repeated voice is more mobile than that of an infrequent one, and then much more susceptible to flowing in the direction of the anterior zone (AM: I.263). Another example of training in animals is found in movements in answer to a master’s voice. These movements consist of approach or escape reactions and the diversity of responses can be explained by certain voices in the past which have been followed by the offer of food whereas others have been produced by punishment. In this case, Pereira explained how the activation of a master’s voice phantasma on the posterior area of an animal’s brain generates the mobilization of the phastasmata of past events that were accompanied by such a voice. Here it is important to note that reward and punishment have a primary role in Pereira’s concept of behavior modification, because they are effective not only in establishing new behaviors but also in favoring learning by imitation (AM: I.263–265).