Aphasia – what now?

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As we saw in part one of the article on the topic of aphasia, even though different types of communication disorders exist, some symptoms tend to overlap. In part two, we will examine how clinicians diagnose speech and communication disorders and which factors influence the recovery for diagnosed patients. Here the focus lies on patients who have been admitted to hospital with some kind of neurological damage, such as stroke. In these cases, the language impairments are only a side effect of the actual medical diagnosis and not the reason for seeing a neurologist. In these situations, patients’ language difficulties can be easily overlooked during treatment.

Ideally, the diagnosis of communication disorders should be by specifically trained speech language pathologists, but these are unfortunately not always available in the ward where the patients are. In the case of stroke, for example, the patient would be in the neurology department, where a large range of medical problems related to the brain or nervous system are treated. On top of being quite busy most of the time, many neurologists and neurosurgeons are not specifically trained for diagnosing communication and language impairments in detail. Sometimes, the nodding of a patient will be interpreted as a successful understanding of the message addressed to them, or patients will not be further examined for language impairments if they are able to produce logical-sounding utterances. This is very problematic, as some patients with language disorders can have very fluent and typical sounding speech, while their understanding can be heavily impaired.

Currently, there are a variety of so-called bedside tests available to screen patients for aphasia directly at the hospital bed, after receiving treatment for their initial diagnosis (e.g. a stroke). These tests are, in theory, designed for a rather quick and conclusive diagnosis of patients’ language impairments. Despite these tests, patients are unfortunately sometimes sent home without a diagnosis of communication impairments, while in reality they do suffer from some type of aphasia. There are two reasons for this: Firstly, clinicians are not always properly trained in performing such tests or correctly interpreting the results. Secondly, not all available test batteries are equally suitable to diagnose the different communication impairments, because they can differ in their focus and sensitivity. One test might, for example, be designed for very specific types of aphasia but fail to detect others, or a test might be designed for very severe impairments and consequently fail to detect mild versions of aphasia. Therefore it might be tempting to come up with one’s own adapted version of such a test or to translate them from one language to another, which is very tricky because languages differ a lot from each other. If these differences are not taken into account when translating the tests, the results may be very untrustworthy. Thus, in order to notice and diagnose a patient’s language difficulties more correctly, we should aim to improve clinicians’ training and develop more specialized, language-specific diagnostic tools.

Once a communication disorder is correctly diagnosed, the patient can start a treatment trajectory and thereby overcome or at least mitigate their impairments. So how much do patients generally improve from their language impairments and what is likely to be the final outcome after treatment? This is a tricky topic, yet probably the most interesting aspect for patients and their families. It is of course crucial that patients get diagnosed properly so that they can receive individually tailored treatment for their abilities and needs. But we are also lucky that our brains are flexible and thus able to adapt to the damage induced by strokes or other head trauma. Roughly, this means that once an area in the brain is damaged and cannot perform its tasks anymore, the performing of these tasks can be redirected to another area, meaning the brain reorganizes itself. This phenomenon is also called neuroplasticity, and is especially interesting in the case of strokes. Compared to a tumor, for example, which allows the brain to gradually adapt as the tumor grows, a stroke is a very sudden type of brain damage. Usually, stroke patients therefore experience the most severe impairments right after suffering a stroke. Since the damage happens unexpectedly, there is no alternative organization in place yet to take over the tasks normally performed by the now-damaged area. Nevertheless, the brain starts working on reorganizing immediately and neuroplasticity kicks in. This is why patients often experience the greatest improvements in the first couple of days after a stroke. Full or partial improvement depends on which areas were damaged and to what degree, but it is fascinating that the brain, unlike many other of our organs, has a way to reorganize itself to try to overcome the inflicted damage.

Currently it is still unclear how exactly neuroplasticity works or what type of reorganization results in the best recovery. For example, the brain may redirect the tasks of damaged areas to the surrounding brain areas, or to the same brain areas in the other, undamaged hemisphere. Some researchers think that areas of the undamaged hemisphere take over first, to give the damaged hemisphere some time to recover. In case of successful recovery of the areas surrounding the damage, the brain may then revert the reorganization and perform the tasks in the areas in the damaged hemisphere again. This idea is, however, still debated, so more research on this topic is needed. If we knew the answer to this question, we could implement this knowledge in patient therapy and thereby greatly improve the final outcome of patients’ communication abilities.

In conclusion, next to early diagnosis and treatment, the extent to which a patient can recover from stroke-induced communication abilities depends on the size and location of the brain damage, the severity of the impairment and the individual plasticity of the brain. Brain plasticity generally declines with age: broadly speaking, the younger a patient is, the better the brain can adapt to the damage and reorganize itself accordingly. In order to optimize the outcome for patients and reach the maximum recovery from brain damage there is still room for improvement in diagnosis as well as treatment, though, not least by means of more research with patient populations. Yet it is astonishing how the brain, aided by therapy and treatment, can adapt to such a devastating physical trauma.

Read part 1 of this blog here.

 

Writer: Natascha Roos
Editors: Sophie Slaats, Sara Mazzini
Dutch translation: Ava Creemers
German translation: Fenja Schlag
Final editing: Eva Poort, Merel Wolf