Dan ZhuCathy GereHISC 11718 January 2018Broca’s subversive theory            Broca’s theory of cerebral localization is such a politically subversive theory. It changed my mind of belief in the phrenology.  We used to be persuaded by phrenologists to think the brain as the organ of the mind, and the mind consists of a series of different functions. Each of which corresponds to a particular area of the brain. These areas are thought to constitute a certain proportion of human characteristics. At the same time, phrenologists also believe that the shape of the skull is related to the shape of these areas in the brain. So, by measuring the human head, one can judge each person’s different personality. Therefore, as long as the hand touches the skull, we can analyze the characteristics of the internal structure of the brain.

We can also analyze a person’s psychological function whether is developed or is lacking. Thus, some people describe “phrenology” as “read augmentation.” Despite academic disapproval, the public seems to be in favor of phrenology, and people even believe that phrenology defines people’s characteristics. These are proved in Broca’s paper to be totally wrong.            Before going into Broca’s new finding, I want to present to you another view from Jean-Pierre Flourens. He believes that although the central nervous system can be divided into several major different parts according to its nature and function, it still forms a unified whole. The functions of the nervous system, especially the brain, are unified. He uses brain function to they that brain is unified that it opposes the division of traditional brain functions.

Freud’s theory of brain function has a great impact on the study of brain science, and the resection method he uses provides an effective method for later animal experimental psychology. Phrenology had been systematically demolished by believers in the unity and indivisibility of the individual human spirit, It’s an important plank of counter-revolutionary ideology.             Here come to Broca’s new views of the brain.

 From Broca’s report we see that “There is a general faculty of language that presides over all these modes of the expression of thought, and it may be defined: the faculty of establishing a constant relation between an idea and a sign, whether this sign be a sound, a gesture, a figure, or any other trace.” There are, in effect, several species of language. Any system of signs permitting the expression of ideas in a manner more or less intelligible, more or less complete, more or less rapid, is a language in the most general sense of the word. Thus, speech, mimicry, typing, picture writing, phonetic writing, etc., are all species of language. Broca            Broca’s opinion is a powerful challenge to Freud’s brain function and further stimulates the study of brain function.

At the same time, the clinical approach adopted by Broca has become a very important supplement to the study of excision because the excision method cannot be applied to humans. Broca’s discovery not only uncovered the special function of the nervous system but also find the brain groove back as a clear sign of brain function partition. Broca’s research shows that speech has a very complicated mechanism.

 Since Broca’s experiment with Tan who lost speech due to the stroke, he discovered the “language spot.” By trace Tan’s language deficit to a small spot in the frontal lobe after Tan died. Broca ‘s finding is subversive to the existing belief. Broca’s definition: “The study of the Human Group, considered as a whole, in its details, and in relation to the rest of nature.” In his detailed written report, Broca devoted to the study of humanity from a biological perspective and challenged the idea of language, race and head shape, and the fact that the third frontal convolution was not exactly where phrenology would locate the speech center.