A language disorder is a communication disorder characterized by an impaired ability to understand and/or use words in their proper context, whether verbal or nonverbal.
Language disorders belong to a broad category of disorders called communication disorders that also include speech and hearing disorders. As of 1998, communication disorders were affecting one person out of every 10 in the United States. Language disorders are characterized by one or more of the following features: sound substitutions in words, difficulty in processing sounds into syllables and words, improper use of words, confusion about their meaning, difficulty in expressing ideas and thoughts, inappropriate use of grammatical forms, limited vocabulary development and inability to follow directions, remember questions or numbers and letters in sequence. Language disorders can be classified as either developmental or acquired.
Developmental language disorders
Developmental language disorders occur in children who do not develop functional language skills. Clinically, they are diagnosed as language-delayed or language-disordered. Language-delayed children can have receptive language impairments, expressive language impairments or both.
Receptive language impairments refer to a difficulty understanding language at the level of meaning. The vocabulary range is usually very limited. The purpose of simple grammatical constructions is also not properly understood. For example, that adding an "-s" to a noun makes it plural, or that "'s" is a possessive form, or that a verb with an "-ed" ending means that the action occurred in the past. There is also difficulty in understanding nonverbal signals, such as body language, or difficulty understanding sarcasm and irony, or indirect requests and sentences.
Expressive language impairments refer to the use of defective language patterns, for example using too few words in sentences. Or the sentences may be truncated, or contain words that lack proper endings, or miss the verbs "is" and "are." Limited or ambiguous vocabulary is also a feature. Affected individuals have difficulty using language properly, and as a result, they often seem rude or
Acquired language disorders
Acquired language disorders, also called aphasias, are language impairments caused by damage to the areas of the brain responsible for language function. Various aspects of language may be affected depending on the location and extent of the brain damage. Language function is believed to be associated with the left hemisphere of the brain and some aphasias are accordingly classified with respect to the affected brain area:
- Broca's aphasia. This type of aphasia is an expressive aphasia and it is associated with damage to Broca's area, a region located in the frontal lobe of the left hemisphere of the brain. It is characterized by an impaired ability to produce language.
- Wernicke's aphasia. This type of aphasia is a receptive aphasia and it is associated with damage to Wernicke's area, a region located in the left temporal lobe of the brain. It is characterized by an impaired ability to understand language.
- Dyslexia. Dyslexia is a neurological learning difficulty that also affects the learning of language skills. It is characterized by an impaired ability to manage verbal codes in memory and difficulties with writing, spelling, and reading. Other symbolic functions, such as mathematics and musical notation, can also be affected.
Causes and symptoms
Developmental language disorders have been associated with a wide variety of causes, such as hearing impairment, cognitive impairment, autism, or a physical handicap that prevents the child from interacting normally with his environment, such as mental retardation, or a cleft lip or palate. Emotional/psychological problems may also be a cause, and lack of intellectual stimulation as well. Often, there is no identifiable cause for a developmental language disorder.
Acquired language disorders or aphasias resulting from brain damage can be caused by cerebral palsy, stroke, tumor or head injury affecting the left hemisphere of the brain. It should be noted that individual differences do exist in brain function and when coupled with differences in the extent of the brain damage, the degree of impairment caused by aphasia is then unique to the affected individual.
Although the symptoms of language disorders vary from one individual to the next, and also depend on whether they are developmental or acquired, they do present a range of characteristic symptoms. Generally speaking, in the case of developmental disorders, a child's language skills are considered delayed when the child is noticeably behind his or her peers in the acquisition of basic language skills. Sometimes a child will have a greater receptive (understanding) impairment than an expressive (speaking) impairment, but the overall result is the same as both functions are required for the full development of language skills.
Some general symptoms are typical of an aphasic language disorder. Most affected individuals experience anomia, or difficulty finding words and some aphasic people try to cope with this difficulty by providing descriptions or definitions for the missing words. This is called circumlocution. Another symptom is paraphasia, meaning the use of an incorrect or unrecognizable word in place of the desired word. There are three types of paraphasias. Phonemic or literal paraphasias are faulty words that sound very close to the intended word (for example, using "bait" instead of "bake"). Verbal or semantic paraphasias are faulty words that are close in meaning to the target word (for example, using "apple" instead of "orange"). The third type of paraphasias are neologisms, or invented words that do not exist in the speaker's language. Another symptom is perseveration, meaning the repetition of a word or sentence when it is not required. The aphasic person gets stuck in a pattern of repetitive sentences without being able to break out of it.
The early diagnosis of language disorders is important because they are first and foremost a communication disorder that always leads to social and educational isolation. Evaluation procedures, usually performed by a speech-language pathologist, are used to diagnose the disorders and any child whose language is not similar to that of other children of the same age should be evaluated. While faulty language patterns are considered normal "baby talk" during early childhood, they become indicative of a language disorder if they are not outgrown as expected. Because of brain development patterns, it is easier to learn language and communication skills before the age of five, thus the importance of timely diagnosis. One or a combination of typical features usually occur in a child affected by a language disorder or developmental language delay. The child may hear or see a word but be incapable of understanding its meaning. He may have trouble getting others to understand what he wants to communicate or display a high level of inattention or lack of organizational skills. These are all pointers that are used to establish diagnosis.
The treatment of language disorders belongs to speech pathology, the specialty concerned with disorders of speech and language. Language therapy with preschoolers is centered on working with parents and other family members to create an optimal environment for learning language. For example, when speaking with a child who has aphasia, it helps to minimize distractions, and to speak slowly and clearly. If the child has difficulty understanding, the use of short and simple sentences is beneficial. Pairing gestures with speech to help comprehension also helps. So does allowing the child ample time to respond and the formulation of questions that can be answered easily with a yes or no or other single word. Speech pathologists can recommend strategies to help families of children with language disorders. School-age children with developmental language disorders can benefit from special education programs, usually monitored by a speech pathologist.
Prognosis is dependent on the cause of the language disorder. If the cause is brain damage, the acquired disorder usually remains. In the case of developmental language disorders, many affected children are able to catch up with their peers, but many also continue to have difficulty with the gap between their skill level and that of their peers, which may increase over time. Since many factors influence outcome, it is not possible to predict which individuals are most likely to recover or how significant the progress will be. Developmental language disorders also have different stages that follow the overall development of children. At different ages, different demands are made on the language system. For example, language-disordered children in the preschool years may appear to catch up to peers by age five or six years, but in later years, as language demands evolve, (e.g., the stage of learning how to read), new impairments usually become apparent.
Health care team roles
Language disorders are usually treated by a speech pathologist working with a collaborative team consisting of the family, physicians, educational professionals as well as special educators. The team usually includes:
- Speech-language pathologists. These specialists have several responsibilities, including: providing individual therapy to the language-impaired; informing teachers and health care professionals on how to identify children who are at risk; performing the evaluation of spoken and written language skills; interviewing family members and teachers; observing the child in the classroom setting so as to evaluate language skills; assessing reading, spelling and writing levels for older children and adolescents.
- Audiologists. Audiologists are specialists of hearing disorders and their expertise may be required in cases where the language disorder is associated with a hearing deficiency.
- Reading specialists. These specialists are special educators who design remedial reading and language skill acquisition therapies.
- Teachers of the language handicapped. These specialized teachers are trained to teach language-delayed children.
There are no specific preventive measures for language disorders, but their early detection will often improve the chances of a successful special education therapy. Thus, identifying children that are at risk of developing a language disorder is important. The following conditions are considered to represent high-risk factors and children exposed to them should be tested early and regularly:
- diagnosed medical conditions, such as chronic ear infections
- biological factors, such as fetal alcohol syndrome
- genetic defects, such as Down syndrome
- neurological defects, such as cerebral palsy
- family history, such as family incidence of literacy difficulties
Anomia—Difficulty finding words.
Aphasia—Acquired language disorder caused by damage to the areas of the brain responsible for language function.
Broca's aphasia—Language disorder associated with damage to Broca's area, a region in the frontal lobe of the left hemisphere of the brain. It is characterized by an impaired ability to produce language.
Communication disorder—Disorder characterized by an impaired ability to communicate. Communication disorders include language, speech and hearing disorders. They are associated with a wide variety of physical and psychological causes.
Dyslexia—Dyslexia is a specific learning difficulty that hinders the learning of literacy skills. This problem with managing verbal codes in memory is neurological and tends to run in families. Other symbolic systems, such as mathematics and musical notation, can also be affected.
Language disorder—Communication disorder characterized by an impaired ability to understand and/or use words in their proper context, whether verbal or nonverbal. The disorder can be either developmental or acquired.
Paraphasia—Use of an incorrect or unrecognizable word.
Speech disorder—Communication disorder characterized by an impaired ability to produce speech sounds or by problems with voice quality.
Speech pathology—The field of speech pathology, formerly known as speech therapy, is concerned with disorders of speech and language. A speech pathologist is a professional trained to diagnose and treat language and speech disorders.
Wernicke's aphasia—Language disorder associated with damage to Wernicke's area, a region in the left temporal lobe of the brain. It is characterized by an impaired ability to understand language.
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Monique Laberge, PhD