Dysphasia and Stroke
There are many things we all take for granted; things we do every day and never think twice about. Our bodies are a vessel enabling us to move in our environment and communicate with other human beings. Under ideal circumstances we are all afforded this fulfilling and enriching experience. However, when this fundamental ability is taken away, we lose part of ourselves, making it difficult to be human. Losing the ability to walk or even talk and do the things that came so easily before can be devastating.
Dysphasia and stroke; losing the ability to speak after experiencing an ischemic or hemorrhagic embolic event is one of those life changing events that happen to millions of people across the globe. Slurred speech after stroke; losing the ability to understand language and express oneself is a fate no one would wish upon another. Lives are forever changed after the events of a stroke, making living life, and doing all the things that make use human a chore.
Our ability to communicate is what makes us the most dominant species on this planet, it is through this we are able to understand each other and work together. Dysphasia and stroke, which precedes it, strip us of that luxury, leaving victims with slurred speech after stroke or worse, with no speech at all.
The brain is often considered the control centre of the entire body, and this goes for controlling speech as well. When the unfortunate circumstance such as dysphasia and stroke occurs, various parts of the brain controlling speech and motor function become compromised due to neuronal death. The left hemisphere of the brain is considered the dominant hemisphere in 99% of the population contain the main control centres for speech and comprehension. When an event happens like dysphasia and stroke, these areas become damaged compromising their function in producing intelligible speech, and comprehension.
Dysphasia is defined as impaired speech communication, and occasionally impaired comprehension of speech as well. This term if often used interchangeably with Aphasia; however this term is used more accurately when describing complete absence of speech from the individual, however both are deemed similar in the same context. There are several reasons why dysphasia and stroke may occur; experiencing a TIA or stroke is the most common owing to its brain damaging effect. Space occupying lesions such as brain tumours, or head injuries could also produce similar effects, not due to a cerebrovascular disease like stroke.
The human brain is divided into regions that serve particular functions. The parietal lobe is responsible for processing sensory information such as taste, temperature, and touch, while the occipital lobe receives information from the optic nerve, deciphering visual information seen through your eyes. Speech and language comprehension also have their specific regions of the brain: Broca’s and Wernicke’s areas respectively. These two areas of the brain are fundamental in human-to-human communication, allowing us to talk and understand what others are saying to us, and being able to follow long and have meaningful conversations. Unfortunately, these areas of the brain are the cause of confusion and frustration for dysphasia and stroke victims.
Located in the lower lateral region of the frontal lobe of the dominant hemisphere, and responsible for speech production and language processing, Broca’s area is fundamental for producing intelligible speech. Persons with damage to this area have difficulty producing speech characterized by simple verbiage, grammar and a distinctively slow delivery. While not being able to communicate effectively, dysphasia and stroke individuals with damage to this area are still able to comprehend every word spoken to them but aren’t able to verbally articulate ideas back in response.
Located in the temporal lobe of the dominant hemisphere, and responsible for language comprehension, Wernicke’s area’s key role is to interpret speech information to be processed and understood by the brain. This function is vital in language recognition and interpretation, as damage would cause a person to have difficulty understanding anyone talking to them, as words coming out of their mouths, the speech would sound like a jumbled mess. Their own speech, however, would not be affected, allowing a person who is suffering from dysphasia and stroke to speak in sentences and be grammatically correct, but they will not make sense in the context of the conversation.
Normally there are there are three structures of the brain that play major roles in processing and speaking words. Sound travels as nerve impulses to the brain reaching Wernicke’s area, where it is analyzed, and then travels to Broca’s area where sounds are assembled into sequences, and then finally these processed impulses are sent to the motor cortex which sends signals and directs movement to the vocal cords and speech muscles.
Treatment for Dysphasia
Experiencing slurred speech after stroke, or losing the ability to communicate all together can drive anyone to seek treatment for dysphasia/aphasia. Dysphasia and stroke patients often seek the aid of a speech-language pathologist. Utilizing speech therapy that aim to improve specific language skills, patients are able to see some improvement from most acute dysphasia/aphasias, as experiencing dysphasia and stroke can leave permanent irreversible side effects in the majority of cases. Some or most language skills can be recovered with speech therapy for stroke victims but can take years to see benefit from results. Effective treatment for dysphasia is often begun quickly after the onset of symptoms, as there is a period of time where spontaneous recovery is possible, as the brain is attempting to mend and restore damaged neurons.
Unfortunately, there isn’t one universal treatment proven to be effective for all types of dysphasia/aphasia, as individuals who experience dysphasia and stroke often vary in presentation, with no two cases being identical. This is why treatment for patients experiencing dysphasia and stroke is often specifically tailored to the specific needs of the patient, with speech therapy for stroke victims showing the most promise.
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