Aphasia are expressive and/or receptive language disorders that occur due to brain injury. With few exceptions, they are also presented with impaired reading and writing. They are very common disorders in people who suffer a stroke and an unknown pathology for much of today’s society.
Aphasia is probably the biggest sequela or limitation, from a personal, social and economic point of view, caused by brain damage. Therefore, adaptation to a sudden loss of language skills involves numerous emotional and cognitive adjustments, since it is through language that people channel their thoughts and communicate with their environment.
Thus, rehabilitation from aphasia should meet the objectives of increasing the language capabilities of the patient and, at the same time, help them cope with their new circumstances, reworking their self-confidence. The sooner treatment begins, and the more frequent the sessions, the better the recovery will be, especially during the first month after injury and during the next six months. Subsequently, the rate of progress decreases, although it does not stop.
However, it is difficult to accurately predict the effect of rehabilitation due to the magnitude of factors involved, including the specifics of the injury (type, location, etiology, size, etc.) and factors inherent to the patient (age, handedness, sex, etc.), there are also other factors that can enhance the treatment such as prior intellectual and educational level, language level, general health and motivation to recovery, among other things.
Conversely, there may also be other associated factors that hamper the recovery such as alterations in the level of consciousness, sensory and motor deficits, epilepsy or depression. Anosognosia or ignorance on the part of the patient that presents disorders is a major obstacle that makes rehabilitation infeasible, the patient must therefore overcome this before having access to the rehabilitation. Patients with anosognosia do not perceive that they present difficulties in expressing or understanding what you say, so they speak using “strange” words in a completely natural way and may find it strange if the other person does not understand them.
There are various clinical types of aphasia, according to the predominance of the impairments in one or other of the aspects of language (expression, comprehension, repetition and designation) and preserved linguistic mechanisms.
- Total or global aphasia: the most severe form of aphasia as a result of massive destruction in the areas concerned with language. It is characterized by significant speech and verbal comprehension impairment. Often the patient presents silence or always emits the same word (stereotypy). Repetition is null. Patients with this type of aphasia may have an attitude of indifference to the environment without communicative intent, looking strangely when you try to interact with them. They cannot speak and cannot understand anything, remaining expressionless and oblivious to what is happening around them.
When understanding improves, but without reaching the levels characteristic of Broca’s aphasia, it is referred to as mixed-motor aphasia. In this case, the patient cannot express themselves, at least not without some effort, but is only able to recite references to time (days of the week, months of the year, etc.) or basic numbers, as well as understand familiar words and everyday expressions such as greetings.
- Motor aphasia or Broca’s aphasia: This is characterized by non-fluid and decreased verbal expression, struggling to speak, reduced sentences, abnormal prosody and suppression of grammatical links (agrammatism). The capacity to repeat is altered, as well as the evocation of names of objects or figures (anomie). The comprehension of spoken language is always better than the production and may present some difficulties in understanding more elaborate syntactic relations. For example, the patient may say a word and understand the majority of things that you say to them. Writing and reading are also often flawed, with numerous errors in spelling and the omission of letters.
- Receptive aphasia or Wernicke’s aphasia: This is characterized by a predominance of comprehension disorders, with normal articulation and fluency in the majority of cases. Verbal expression is usually increased, with some degree of excitement, and an ignorance of the problem on the part of the patient. Although oral production is effortless, with good articulation and prosody, the unintelligible words predominate (aphasic transformations or paraphasia), leading to jargon that is difficult to understand and that is void of content. In cases where no excessive expression occurs (logorrhea), the lack of words is emphasised (anomie). The capacity for repetition and designation is also affected. Comprehension disorder is the most significant, albeit with varying intensity depending on the severity of the injury. For example, the patient does not understands what they are told very well, although they can express themselves, it is difficult to understand due to the use of “strange” or inappropriate words, similar to a foreign language, making it difficult to hold a conversation, reading and writing are also impaired. Although there is an ability to write, these patients express themselves in writing in the same way as they speak, therefore their writing is often difficult to understand.
- Conduction aphasia: characterized by fluent expressive language, with some anomie and paraphasia and an impaired ability to repeat. Patients may have difficulty understanding more complex material. In this case, patients may speak and understand relatively normally, but with some pauses when speaking due to not being able to find the right word, or they may replace the word with another that does not correspond, presenting greater difficulty regarding repetition. Reading is also greatly impaired, while writing is preserved, albeit with many mistakes during dictation, and it is spontaneous.
- Anomic or nominal aphasia: is characterized by fluent expressive language, with normal articulation and structure, but with difficulty in evoking words (anomie). Circumlocutional verbal expression can appear (describing a word that you cannot remember) and general words (they use the same word to communicate). Moreover, anomic deficit can appear in spontaneous speech only, it being almost normal in naming an image. For example, these patients have a sense of knowing what they mean or “they have the word on the tip of their tongue”, but fail to be able to say it, so they explain the characteristics or use of the object that they are trying to name. Although understanding is preserved, they may have difficulties in more elaborate tasks. In reading and writing some errors may occur, difficulty finding the right word when writing being more evident.
- Transcortical motor aphasia: This is characterized by very small spontaneous expressive language (not fluent). The expression is made with effort, and is slow and brief. The designation of images is impaired, while the capacity for repetition is better. Comprehension can be relatively preserved. These patients speak very little and with effort, but are able to repeat much better. They may also have reduced writing capacity, while oral reading and reading comprehension are preserved, although they may be dissociated, i.e., do not usually understand what they read. If the picture improve progression to an anomic aphasia may be possible.
- Transcortical sensory aphasia: characterized by a dissociation between a good capacity for repetition and a defect in the comprehension of words that the patient can repeat, i.e., patients do not understand what they repeat. The verbal expression is fluent in the form of jargon with a prevalence of echolalia (repeating words that are heard). Oral comprehension is usually highly impaired. These patients can repeat very well, but are not able to understand what they repeat. Reading ability may be affected to different degrees and reading comprehension is usually severely impaired. Written expression also appears as jargon that is difficult to understand, i.e., patients write as they speak.
- Mixed transcortical aphasia: This is characterized by significant speech and verbal comprehension impairment. The verbal expression is reduced to echolalia and there is no capacity to describe images. In this case, patients cannot express or understand well, but are able to repeat, recite, complete words and phrases, etc. Both reading and writing and reading comprehension are highly impaired.
The different clinical types of aphasia described are the most common and may progress throughout the treatment, going from one set of circumstances to another less serious set of circumstances depending on the improvement achieved.