Language disorder is a condition that causes difficulty in a person understanding what others say, or sharing their thoughts, ideas and their feelings in a comprehensive manner (Catts, 1996). This condition is caused by factors like stroke and many others. Language disorder takes various forms that include aphasia. Aphasia is the disability that is characterized by an individual losing the ability to express and understand speech because of the damages that occur to the brain (Harley, 2007). There are various types of aphasia. This essay will discuss two types aphasia, Broca’s and Wernicke’s, in a more detailed manner.
It is a non-fluent type of aphasia that is associated with poor retention, auditory comprehension that is relatively good, agrammatic speech and verbal apraxia (Carrol, 1984). The fact the Broca’s area of the brain is located on the left side of the brain accounts for the weaknesses of the muscles of the leg and hand on the right side of the body (Munro, 2010). An individual suffering from apraxia experience difficulties with speaking. This problem is caused by the failure of the articulators to coordinate to form correct patterns that produce words (Robinson and Aitchison, 1999). Apraxia comes into play when an individual voluntarily tries to repeat or repeat certain words.
A person with Broca’s aphasia has a comprehension percentage that ranges between 50% and 90%. To enhance how much such a person comprehends, a speaker should employ gestures in the process of giving a speech (Stark and Aitchison, 1996). The speaker should also write out keywords while speaking and also concentrate on contextual topics. For example, when asking someone what cloth he/she wishes to wear, it is advisable to gesture wearing while pointing to a pair of trousers or a dress. It is not contextual to ask someone what they wish to wear while in the field playing or while watching television.
In addition to that, Broca’s aphasia manifests itself in agrammatic or telegraphic speech (Urwin, 1984). This means that the affected person speaks mostly in nouns and is only able to produce a few words at a time. The time of communication given in this case is non-fluent. This means that the average size of sentence provided by such person is three to five words.
The green region represents the back part of the temporal lobe of the left hemisphere. This is where Wernicke’s aphasia affects (Van Lancker Sidtis, 2012).
Wernicke’s aphasia is characterized by the poor repetition, fluent speech, and poor auditory processing. The auditory processing means that the person that has this type of aphasia has difficulty in understanding what you are saying. Although the person may nod or act to show he/she knows what is being said, what they hear is not often what is being said (Farrell and Farrell, 2010). Fluent speech refers to a case where the individual communicates in full sentences though they may have neologisms and paraphasias. Neologisms refer to a case where an individual uses a word whose spelling does not come close to the intended word. For example, an individual may say ‘skucker` instead of cook. Paraphasias, on the other hand, refers to the use of a word that has one letter misspelt(Hewlett, 1984). For instance, one may say ‘sook’ when the intended word is cook. Poor repetition comes into play when the individual is unable to repeat what they have just said.
Wernicke’s aphasia is caused by damage to the left side of the brain. This is the part of the brain that is responsible for our capability to read, think of what to write or understand information (LaPointe, 2004). Damage to this side of the brain does not cause weaknesses on the hands and legs on the right side of the brain as it happens with Broca`s aphasia. There is, however, some slight weakness, though the individual can walk or use his/her hand just like before stroke.
Language disorders and normality
Cerebrovascular accidents are responsible for strokes (MacDonald, 1999). Aphasia affects the ability to read, write and speak. These abnormalities in the use of language inform us about the normality by having a comprehensive look at the causes. Aphasic studies of language made language the first cognitive function to be localized in the brain (Marinac and Harper, 2009). Aphasia is split into two parts: fluent and non-fluent.
Non-fluent aphasia refers to speech that is slow, stilted and interrupted (motor aphasia). This is majorly related to Broca’s aphasia. This type of aphasia is caused by damage to Broca’s area. Learners with this disorder exhibit slow, halting and laborious speech that is full of inflexionsand phonemes that are difficult (Murdoch and Theodoros, 2001). These learners exhibit dysprosody in speaking. This means that they speak with a lack of proper language intonation, due to word separation.
All types of speeches are controlled by the front lobe (Paul et al., 2000). Therefore, damage to this part of the brain is thought to impair motor control of speech. However, patients with such injuries can still perform the required facial muscle activities like sucking and blowing. They only have a mild weakness on the right side of the muscles in the face, but they can perform other actions normally. Those who suffer from these language disorders tend to speak the way they write.
Today, we are constantly learning new things about the use of language and how it works. For instance, we now believe that the right part of the brain helps in comprehension of metaphors, intonation patterns, and poetic meters. We also understand that language happens in the same way, either verbally or non-verbally. In comprehension of knowledge of language, the disorders have helped in the understanding of how the brain treats nouns and verbs. This hasbeen discussed below.
Nouns and verbs
The brains give quite different treatments nouns and verbs. It is also worth noting that a child will always learn nouns before they learn to use verbs. On the other hand, adults exhibit a very fast reaction to nouns when they are subjected to cognitive tests. This shows that the activity upon learning of a new noun occurs in the left fusiform while gyrus. On the other hand, the left posterior medial temporal gyrus helps in the processing of grammar. The same regions that were in the past associated with the representation of meanings of nouns and verbs are also responsible for the establishment of correspondences between the meanings and the new words. These help one to learn a new language.
The brains of those people that are adeaf function in very much the same way as those of their counterparts that have the ability to hear. Whether someone is using signs while communicating or not, the same part of the brain is activated.
From the two language disorders that have been discussed above, it can be deduced that language works in many ways. One of the ways is by repetition. When a child is exposed to anew language for the first time, he/she faces difficulty in articulating words and sentences correctly. The child will require constant repetition to try and utter the words correctly. First, the child experiences problems with correct pronunciation of words. This takes place by the child misplacing letters in words when pronouncing them, such that the word looks very different from the intended word. Others will replace one letter with another letter so that the words form a completely different meaning. For example, a child may use the word ’dook’ instead of abook. However, after several attempts by the learner to pronounce the word, the desired outcome may be achieved.
How the study of Broca’s and Wernicke’s aphasias helps us understand normal language functioning
The studies show that language is a localized function because all the processing pertaining to it takes place inside the dominant hemisphere that is made up of the Broca’s area and the Wernicke’s area. The Broca’s area is mostly involved inspeech production. Since this area is in close proximity to the motor cortex, signals are sent from the Broca’s area by neurons to the motor areas of the larynx, tongue and mouth. These parts in turn send the received signals to the concerned muscle. This process leads to the creation of sound. The Broca’s area is responsible for both phonological and semantic fluency.
Wernicke’s area on the other hand helps one to comprehend words that are ambiguous, regardless of whether they heard or written. This area is majorly concerned with receptive speech. The main function of this area is to help one to comprehend language and communicate ideas that are coherent. This happens with all types of language; signed, written and vocal.