Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Agrammatism is a characteristic of non-fluent aphasia. Individuals with agrammatism present with speech that is characterized by containing mainly content words, with a lack of function words. For example, when asked to describe a picture of children playing in the park, the client responds with, "trees..children..run." People with agrammatism may have telegraphic speech, a unique speech pattern with simplified formation of sentences (in which many or all function words are omitted), akin to that found in telegraph messages. Deficits in agrammaticism are often language-specific, however—in other words, "agrammaticism" in speakers of one language may present differently from in speakers of another.
Errors made in agrammatism depend on the severity of aphasia. In severe forms language production is severely telegraphic and in more mild to moderate cases necessary elements for sentence construction are missing. Common errors include errors in tense, number, and gender. Patients also find it very hard to produce sentences involving "movement" of elements, such as passive sentences, wh-questions or complex sentences.
Agrammatism is seen in many brain disease syndromes, including expressive aphasia and traumatic brain injury.
People with aphasia may experience any of the following behaviors due to an acquired brain injury, although some of these symptoms may be due to related or concomitant problems such as dysarthria or apraxia and not primarily due to aphasia. Aphasia symptoms can vary based on the location of damage in the brain. Signs and symptoms may or may not be present in individuals with aphasia and may vary in severity and level of disruption to communication. Often those with aphasia will try to hide their inability to name objects by using words like "thing". So when asked to name a pencil they may say it is a thing used to write.
- Inability to comprehend language
- Inability to pronounce, not due to muscle paralysis or weakness
- Inability to speak spontaneously
- Inability to form words
- Inability to name objects (anomia)
- Poor enunciation
- Excessive creation and use of personal neologisms
- Inability to repeat a phrase
- Persistent repetition of one syllable, word, or phrase (stereotypies)
- Paraphasia (substituting letters, syllables or words)
- Agrammatism (inability to speak in a grammatically correct fashion)
- Dysprosody (alterations in inflexion, stress, and rhythm)
- Incomplete sentences
- Inability to read
- Inability to write
- Limited verbal output
- Difficulty in naming
- Speech disorder
- Speaking gibberish
- Inability to follow or understand simple requests
Given the previously stated signs and symptoms the following behaviors are often seen in people with aphasia as a result of attempted compensation for incurred speech and language deficits:
- Self-repairs: Further disruptions in fluent speech as a result of mis-attempts to repair erred speech production.
- Speech disfluencies: Include previously mentioned disfluencies including repetitions and prolongations at the phonemic, syllable and word level presenting in pathological/ severe levels of frequency.
- Struggle in non-fluent aphasias: A severe increase in expelled effort to speak after a life where talking and communicating was an ability that came so easily can cause visible frustration.
- Preserved and automatic language: A behavior in which some language or language sequences that were used so frequently, prior to onset, they still possess the ability to produce them with more ease than other language post onset.
Broca's (expressive) aphasia is a type of non-fluent aphasia in which an individual’s speech is halting and effortful. Misarticulations or distortions of consonants and vowels, namely phonetic dissolution, are common. Individuals with expressive aphasia may only produce single words, or words in groups of two or three. Long pauses between words are common and multi-syllabic words may be produced one syllable at a time with pauses between each syllable. The prosody of a person with Broca's aphasia is compromised by shortened length of utterances and the presence of self-repairs and disfluencies. Intonation and stress patterns are also deficient.
For example, in the following passage, a patient with Broca's aphasia is trying to explain how he came to the hospital for dental surgery and it may look like this:Yes... ah... Monday... er... Dad and Peter H... (his own name), and Dad... er... hospital... and ah... Wednesday... Wednesday, nine o'clock... and oh... Thursday... ten o'clock, ah doctors... two... an' doctors... and er... teeth... yah.The speech of a person with expressive aphasia contains mostly content words such as nouns, verbs, and some adjectives. However, function words like conjunctions, articles, and prepositions are rarely used except for “and” which is prevalent in the speech of most patients with aphasia. The omission of function words makes the person's speech agrammatic. A communication partner of a person with aphasia may say that the person's speech sounds telegraphic due to poor sentence construction and disjointed words. For example, a person with expressive aphasia might say "Smart... university... smart... good... good..."
Self-monitoring is typically well preserved in patients with Broca's aphasia. They are usually aware of their communication deficits, and are more prone to depression and outbursts from frustration than are patients with other forms of aphasia.
In general, word comprehension is preserved, allowing patients to have functional receptive language skills. Individuals with Broca's aphasia understand most of the everyday conversation around them, but higher-level deficits in receptive language can occur. Because comprehension is substantially impaired for more complex sentences, it is better to use simple language when speaking with an individual with expressive aphasia. This is exemplified by the difficulty to understand phrases or sentences with unusual structure. A typical patient with Broca's aphasia will misinterpret "the man is bitten by the dog" by switching the subject and object to “the dog is bitten by the man.”
Typically, people with expressive aphasia can understand speech and read better than they can produce speech and write. The person's writing will resemble his or her speech and will be effortful, lacking cohesion, and containing mostly content words. Letters will likely be formed clumsily and distorted and some may even be omitted. Although listening and reading are generally intact, subtle deficits in both reading and listening comprehension are almost always present during assessment of aphasia.
Because Broca's area is anterior to the primary motor cortex which is responsible for movement of the face, hands, and arms, a lesion affecting Broca's areas may also result in hemiparesis (weakness of both limbs on the same side of the body) or hemiplegia (paralysis of both limbs on the same side of the body). The brain is wired contralaterally, which means the limbs on right side of the body are controlled by the left hemisphere and vice versa. Therefore, when Broca's area or surrounding areas in the left hemisphere are damaged, hemiplegia or hemiparesis often occurs on the right side of the body in individuals with Broca's aphasia.
Severity of expressive aphasia varies among patients. Some people may only have mild deficits and detecting problems with their language may be difficult. In the most extreme cases, patients may be able to produce only a single word. Even in such cases, over-learned and rote-learned speech patterns may be retained- for instance, some patients can count from one to ten, but cannot produce the same numbers in novel conversation.
In addition to difficulty expressing oneself, individuals with expressive aphasia are also noted to commonly have trouble with comprehension in certain linguistic areas. This agrammatism overlaps with receptive aphasia, but can be seen in patients who have expressive aphasia without being diagnosed as having receptive aphasia. The most well-noted of these are object-relative clauses, object Wh- questions, and topicalized structures (placing the topic at the beginning of the sentence). These three concepts all share phrasal movement, which can cause words to lose their thematic roles when they change order in the sentence. This is often not an issue for people without agrammatic aphasias, but many people with aphasia rely heavily on word order to understand roles that words play within the sentence.
Transcortical motor aphasia (TMoA), also known as commissural dysphasia or white matter dysphasia, results from damage in the anterior superior frontal lobe of the language-dominant hemisphere. This damage is typically due to cerebrovascular accident (CVA). TMoA is generally characterized by reduced speech output, which is a result of dysfunction of the affected region of the brain. The left hemisphere is usually responsible for performing language functions, although left-handed individuals have been shown to perform language functions using either their left or right hemisphere depending on the individual. The anterior frontal lobes of the language-dominant hemisphere are essential for initiating and maintaining speech. Because of this, individuals with TMoA often present with difficulty in speech maintenance and initiation.
Damage in the watershed region does not directly harm the areas of the brain involved in language production or comprehension; instead, the damage isolates these areas from the rest of the brain. If there is damage to the frontal lobe, executive functions related to language use are often affected. Executive functions relevant to language include activating language responses, controlling syntax (grammar), and narrative discourse. Difficulties in these areas can lead to supplementary deficits involving difficulties forming complex sentences, choosing which words to use appropriately, and initiating speech in conversation.
The extent and location of the brain damage will impact the degree and variety of language functioning characteristics (i.e. damage deep to the frontal lobe and/or damage across multiple regions will greatly impair language). Right hemiparesis, or right-sided paralysis, may coincide with TMoA if the lesion in the anterior frontal lobe is large enough and extends into the posterior frontal lobe.
There are some other forms of aphasia that relate to TMoA. For instance, adynamic aphasia is a form of TMoA that is characterized by sparse speech. This occurs as a result of executive functioning in the frontal lobe. Another form of aphasia related to TMoA is dynamic aphasia. Patients with this form of aphasia may present with a contiguity disorder in which they have difficulty combining linguistic elements. For dynamic aphasia, this is most apparent when the patient is asked to sequence at the sentence level whereas for other aphasias contiguity disorder can be seen at the phoneme or word level.
TMoA is classified as a non-fluent aphasia that is characterized by a significantly reduced output of speech, but good auditory comprehension. Auditory comprehension skills remain intact because the arcuate fasciculus and Wernicke's area are not impaired. Individuals with TMoA also exhibit good repetition skills and can repeat long, complex phrases effortlessly and without error. However, spontaneous speech often presents with paraphasias (a term used to describe a wide variety of speech errors that are caused by aphasia). Regardless of any relative communication strengths, individuals with TMoA are typically poor conversational partners. Due to damage in the anterior superior frontal lobe, people with TMoA have deficits in initiation and maintenance of conversations, which results in reduced speech output. A person with TMoA may seldomly produce utterances and typically remain silent. The utterances that they do produce are typically only one to two words long. However, in more structured and predictable interactions, individuals with TMoA tend to respond more fluently and promptly. In addition, these individuals are characterized by their attentiveness and cooperation and are often described as being task-oriented.
The main clinical features are signature language progressive difficulties with speech production. There can be problems in different parts of the speech production system, hence patients can present with articulatory breakdown, phonemic breakdown (difficulties with sounds) and other problems. However, it is rare for patients to have just one of these problems and most people will present with more than one problem. Features include:
- Hesitant, effortful speech
- Speech 'apraxia'
- Stutter (including return of a childhood stutter)
- Anomia
- Phonemic paraphasia (sound errors in speech e.g. 'gat' for 'cat')
- Agrammatism (using the wrong tense or word order)
As the disease develops, speech quantity decreases and many patients will become mute.
Cognitive domains other than language are rarely affected early on. However, as the disease progresses other domains can be affected. Problems with writing, reading and speech comprehension can occur as can behavioural features similar to frontotemporal dementia.
There is some confusion in the terminology used by different neurologists. Mesulam's original description in 1982 of progressive language problems caused by neurodegenerative disease (which he called primary progressive aphasia (PPA) included patients with progressive non-fluent (PNFA), semantic dementia (SD), and logopenic progressive aphasia (LPA).
The CCAS has been described in both adults and children. The precise manifestations may vary on an individual basis, likely reflecting the precise location of the injury in the cerebellum. These investigators subsequently elaborated on the affective component of the CCAS, i.e., the neuropsychiatric phenomena. They reported that patients with injury isolated to the cerebellum may demonstrate distractibility, hyperactivity, impulsiveness, disinhibition, anxiety, ritualistic and stereotypical behaviors, illogical thought and lack of empathy, aggression, irritability, ruminative and obsessive behaviors, dysphoria and depression, tactile defensiveness and sensory overload, apathy, childlike behavior, and inability to comprehend social boundaries and assign ulterior motives.
The CCAS can be recognized by the pattern of deficits involving executive function, visual-spatial cognition, linguistic performance and changes in emotion and personality. Underdiagnosis may reflect lack of familiarity of this syndrome in the scientific and medical community. The nature and variety of the symptoms may also prove challenging. Levels of depression, anxiety, lack of emotion, and affect deregulation can vary between patients. The symptoms of CCAS are often moderately severe following acute injury in adults and children, but tend to lessen with time. This supports the view that the cerebellum is involved with the regulation of cognitive processes.
Cerebellar cognitive affective syndrome (CCAS), also called "Schmahmann's syndrome" is a condition that follows from lesions (damage) to the cerebellum of the brain. This syndrome, described by Dr. Jeremy Schmahmann and his colleagues refers to a constellation of deficits in the cognitive domains of executive function, spatial cognition, language, and affect resulting from damage to the cerebellum. Impairments of executive function include problems with planning, set-shifting, abstract reasoning, verbal fluency, and working memory, and there is often perseveration, distractibility and inattention. Language problems include dysprosodia, agrammatism and mild anomia. Deficits in spatial cognition produce visual–spatial disorganization and impaired visual–spatial memory. Personality changes manifest as blunting of affect or disinhibited and inappropriate behavior. These cognitive impairments result in an overall lowering of intellectual function. CCAS challenges the traditional view of the cerebellum being responsible solely for regulation of motor functions. It is now thought that the cerebellum is responsible for monitoring both motor and nonmotor functions. The nonmotor deficits described in CCAS are believed to be caused by dysfunction in cerebellar connections to the cerebral cortex and limbic system.
Agrammatism was first coined by Adolf Kussmaul in 1887 to explain the inability to form words grammatically and to syntactically order them into a sentence. Later on, Harold Goodglass defined the term as the omission of connective words, auxiliaries and inflectional morphemes, all of these generating a speech production with extremely rudimentary grammar. Agrammatism, today seen as a symptom of the Broca's syndrome (Tesak & Code, 2008), has been also referred as 'motor aphasia' (Goldstein, 1948), 'syntactic aphasia' (Wepman & Jones, 1964), 'efferent motor aphasia' (Luria, 1970), and 'non-fluent aphasia' (Goodglass et al., 1964).
The early accounts of agrammatism involved cases of German and French participants. The greater sophistication of the German school of aphasiology at the turn of the 20th century and also the fact that both German and French are highly inflected languages, might have been triggers for that situation (Code, 1991). Nowadays, the image has slightly changed: grammatical impairment has been found to be selective rather than complete, and a cross-linguistic perspective under the framework of Universal Grammar (UG) together with a shift from morphosyntax to morphosemantics is à la page. Now the focus of study in agrammatism embraces all natural languages and the idiosyncrasies scholars think a specific language has are put in relation to other languages so as to better understand agrammatism, help its treatment, and review and advance in the field of theoretical linguistics.
There is little written about agrammatism in Catalan. The beginnings of the field should be encountered in the work of Peña-Casanova & Bagunyà-Durich (1998), and Junque et al. (1989). These papers do not describe case reports, they are rather dealing with more general topics such as lesion localization or rehabilitation of agrammatic patients. The most updated studies could be found in the work of Martínez-Ferreiro (2009). The work of Martínez-Ferreiro is under the so-called Tree Pruning Hypothesis (TPH) of Friedmann & Grodzinsky (2007). Such a hypothesis is somewhat lagging behind after the findings in Bastiaanse (2008) have been proved by means of a re-analysis of data from Nanousi et al. (2006) and Lee et al. (2008), and the work of Yarbay Duman & Bastiaanse (2009). Other rather updated work for agrammatism in Catalan should be found in Martínez-Ferreiro et Gavarró (2007), in Gavarró (2008, 2003a, 2003b, 2002), Balaguer et al. (2004), in Peña-Casanova et al. (2001), and in Sánchez-Casas (2001).
From a cross-linguistic perspective under the framework of Universal Grammar (UG), grammatical impairment in agrammatism has been found to be selective rather than complete. Under this line of thought, the impairment in tense production for agrammatic speakers is currently being approached in different natural languages by means of the study of verb inflection for tense in contrast to agreement (a morphosyntactic approach) and also, more recently, by means of the study of time reference (which, in a sense, should be seen closer to morphosemantics). The type of studies this paper should be related with are those dealing with tense impairment under the framework of time reference. Prior to explaining that, to help understand the goals of such research, it is good to give a taste of the shift from morphosyntax to morphosemantics the study of agrammatism is undergoing.