Introduction
Over the years, research on how the brain perceives and processes language has intensified. From as early as 1861, evidence from studies has confirmed that the brain is a fundamental component with regards to the process of learning languages. The study of the biological and neural basics of a language is referred to as neurolinguistics. Research in this field is often based on data from impaired languages. The data is used to understand the properties associated with the linguistic aspect of human existence (Fromkin, Rodman and Hyams 461).
Recent advancements in technology have made it possible for researchers to explore other methods of studying the brain. Such approaches include the use of Functional Magnetic Resonance Imaging (FMRI), Positron Emission Tomography (PET), and functional MRI (fMRI) technologies. The tools are used by researchers to map the brain (Fromkin et al. 468).
In this paper, the author provides a critical analysis of the major linguistic parts of the brain. The parts include those responsible for language processing and creation. In addition, the author will highlight the linguistic complications that may arise due to damages or dysfunctions associated with those parts. To this end, the author will focus on damages and dysfunctions brought about by medical impairments.
Impacts of Medical Impairment on Linguistic Areas of the Human Brain
Overview
The brain is composed of two major regions. They include the left and the right hemispheres. The left region is the one responsible for language perception and processing. On the other hand, the right side is responsible for human imagination. The two sides are connected by fibers known as corpus callosum. The left side of the human body is controlled by the right side of the brain. On its part, the right side of the body is regulated by the left side of the brain. The situation is referred to as contralateral brain function (Fromkin et al. 461). Medical impairment to any linguistic part of the brain leads to various complications.
Aphasia
Aphasia is a term used to describe a language disorder brought about by damaged brain parts. The impairment is mostly caused by stroke and brain tumor (Fromkin et al. 463). Medically, aphasia is broadly categorized into two clusters. The two are fluent and non-fluent aphasias. The first category involves a situation where an individual speaks fluently but has trouble processing and understanding speech. On the other hand, patients with non-fluent aphasia understand other people well but have a problem with their own speech. They usually utter a few words, which may sound senseless. However, linguists classify aphasia according to their area of localization. The areas in reference are the regions of the brain that cause these complications.
Broca’s area
The Broca’s area is located at the front of the left hemisphere. It is named after a French neurologist who discovered it in 1861. Medical damage to this region leads to the development of a condition referred to as Broca’s or expressive aphasia. Patients with this condition have no problem processing speech. However, they find it hard to express themselves verbally or through writing (Fromkin et al. 467). Information in the brain is usually moved to the Broca’s area from the Language Axis (Obler and Gjerlow 45). In the Broca’s region, the information received is arranged both grammatically and syntactically.
The organized information is then moved in form of electric pulses to the front motor areas. According to Fromkin, the motor areas are responsible for the verbal musculature (73). The musculature makes it possible for verbal expression to take place.
When the Broca’s area is damaged, the brain fails to arrange a person’s thoughts grammatically. People with this condition may find it hard to understand sentences whose apprehension relies entirely on syntax and grammar (Fromkin et al. 465). In severe cases, the frontal motor areas of the brain, which are adjacent to the Broca’s region, may be damaged. The impairment makes it hard for the individual to move their mouth to produce speech. Since the left frontal lobe is also responsible for the activities taking place in right side of the body, most right-handed people may have difficulties when writing due to paralysis (Fromkin et al. 461).
Wernicke’s area
The area is adjacent to the auditory cortex. It was discovered by a German neurologist, Carl Wernicke, 10 years after the Broca’s area became known (Aniruddh 56). The region is believed to be responsible for the processing of both verbal and written languages. Medical impairment to this area, such as lesions, may lead to the development of a condition known as Wernicke’s or receptive aphasia. Patients suffering from this condition find it hard to understand both spoken and written language.
In addition, it is hard for them to make grammatical sense while speaking. It is important to note that the speaking capability of receptive aphasics remain intact. However, they may still find it hard to express themselves when speaking (Fromkin et al. 467). The situation is attributed to the fact that even though the Broca’s area remains intact, the Wernicke’s region still plays a vital role in the linguistic output of a person.
Patients suffering from receptive aphasia may produce sentences that may be correct with regards to syntax. However, they are overly incoherent in their semantics (Fromkin et al. 465). At later stages of this condition, the patients have problems finding the correct word to use in self-expression. In addition, they may overstep the phonetic boundary (Shanahan 30). As a result, the individual confuses closely related words. Consequently, what they say or write may be totally different from what was intended. Their ability to memorize and recite words is, however, unaffected. In addition, their writing abilities are usually intact. However, the content of their written communication makes little or no sense. It is noted that most of these patients are unaware of their disability (Shanahan 32).
Arcuate fasciculus
The Broca’s and Wernicke’s areas are located in different lobes of the brain. However, the two areas are connected by nerve fibers, which make it possible for them to communicate (Fromkin et al. 470). The fibers in reference are known as arcuate fasciculus (Obler and Gjerlow 99). Supramarginal gyrus, also known as angular gyrus, is located above these fibers. They are found halfway between the Broca’s and Wernicke’s areas.
Medical damage to arcuate fasciculus leads to a condition known as conductive aphasia (Aniruddh 82). Individuals with this condition are usually better off compared to those with receptive and expressive aphasias. People with this condition comprehend and process speech normally. In addition, they speak fluently and are always aware of what they are saying. Medical impairment of angular gyrus is associated with such conditions as alexia, dyslexia, and agraphia. Alexia is the inability to read. On its part, dyslexia involves problems when reading. Finally, agraphia is the inability to write (Fromkin et al. 466).
In some cases, a person may experience both receptive and expressive aphasias. The condition is referred to as global aphasia. It is due to extensive medical damage to the frontal and parietal lobes. In some cases, patients with global aphasia also experience paralysis on their left side. As a result, they have problems when writing. Linguistic comprehension and expression is also greatly reduced. The same applies to the individual’s ability to repeat.
Transcortical sensory aphasia
Another rare form of linguistic impairment is the transcortical sensory aphasia. The condition is not as a result of medical damage to any linguistic part of the brain. On the contrary, it occurs when the three major linguistic parts of the brain (the Broca’s, Wernicke’s, and arcuate fasciculus areas) are separated from the rest of the brain. The situation mainly occurs due to insufficient vascular composition, which leads to impaired blood supply (Fromkin et al. 45). Patients with this condition exhibit extensive memorizing abilities. In addition, they can repeat long sentences. However, their writing and reading abilities are absent even when no paralysis of the limbs is experienced (Aniruddh 77).
Conclusion
Over the years, studies conducted on the brain have made it possible for linguists to better understand how this organ works. The studies provide information on how the brain helps people to communicate and perceive language. There was a time when study of this organ involved mere observations of physical traits of a person. However, recent technological advancements have made it possible for researchers to study the brain more efficiently. The development has provided linguists with better understanding of the parts of the brain tied to linguistics. Technological advancement also provides information on complications that may arise due to medical impairment of such regions.
Works Cited
Aniruddh, Patel. Music, Language, and the Brain, Oxford: Oxford University Press, 2010. Print.
Fromkin, Victoria, Robert Rodman, and Nina Hyams. An Introduction to Language. 8th ed. 2007. Boston, MA: Thomson Wadsworth. Print.
Fromkin, Victoria. ‘Brain, Language, and Linguistics,’ Brain and Language 71.1 (2000): 72-74. Print.
Obler, Loraine, and Kris Gjerlow. Language and the Brain, Cambridge, UK: Cambridge University Press, 1999. Print.
Shanahan, Daniel. Language, Feeling, and the Brain: The Evocative Vector, New Brunswick, N.J.: Transaction Publishers, 2007. Print.