Language and the brain

Language and the brain

1. The hemispheres of the brain

   • Is that of a whole which is divided into vertical halves that seem to be mirror of one another
   • The hemispheres maintain connection with one another through a bundle of fibres called the corpus callosum
   • Each cerebral hemisphere is divided into four parts or lobes: from front to back there are the frontal, temporal, parietal (located above the temporal), and the occipital. This division of the brain into lobes is loosely based on physical features and not on actual separations
     • General functions such as cognition, occur in the frontal lobe, hearing occurs in the temporal lobe, general somaesthetic sensing (feeling in the arms, legs, face, etc.) In the parietal lobe, and vision in the occipital lobe. Each hemisphere has these lobes with these functions. There are other hemispheric-specific functions that are also located in some of these areas.
       • The left hemisphere typically involves language

2. Language areas and their functioning

   • Broca's area is one of the main areas of the cerebral cortex responsible for producing language. For a long time it was assumed that the role of Broca's area was mainly dedicated to the production of language and not so much to the understanding of it.
     • However, there is evidence showing that Broca's area also plays an important role in language understanding. Broca's area is connected to Wernicke's area by a bundle of nerve fibers called the arcuate fasciculus (or arcuate); this area of the brain limits with the angular gyrus of the parietal lobe, involved in language, reasoning and memory
   • Broca's area is located in the lower portion of the left frontal lobe and controls motor functions related to the production of speech; Through it we can communicate with greater precision of our ideas; likewise to understand our language. In relation to Wernick's area, the processing of spoken and written language is carried out.

3. Sing Language

   • The left hemisphere appears to be centrally involved in sign language, as it is with non-signers. The right hemisphere also is intricately involved with signers but in ways different from that of non-signers.

4. Language disorders: aphasias

   • Language disorders, known as aphasias, are presumed to have as their cause some form of damage to some specific site in the hemisphere where language is located
   • Such damage causes characteristic problems in speech, as well as in reading and writing.
   • Expressive aphasia: knows what wants to say, but has difficulty saying or writing it
   • Receptive aphasia: you hear your voice or you can read a form, but you do not make sense of what you read or hear
   • Anomic aphasia - You have trouble using the correct words to describe objects, places, or events
   • Global aphasia: the patient cannot speak, understand what is being said, read or write