Various diseases and disorders can cause delayed or atypical language development. These include various neurological diseases such as mental retardation, cleft palate, brain injuries, autism, deafness, epilepsy, cerebral palsy, head trauma, neurodegenerative diseases and migration anomalies. However, in the absence of all these, there may be delays and problems in language development without a specific disease or disorder or a demonstrable brain lesion. In this case developmental language disorder diagnosis is mentioned. The term specific language disorder, which has the same meaning, is still widely used in the literature.
Speech delay in children is quite common. Various speech and language problems are seen in 5-20% of children aged 5 years and younger, 1-2% being severe. Some of these children have only speech disorders, some only have developmental language problems, and some have mixed language and speech problems.
Importance of Early Diagnosis and Pre-diagnosis Attitude of the Family
One of the problems in diagnosis is that normal language development is very variable and it is difficult to determine the diagnostic criteria. Language development differs greatly from child to child. In addition, gender, family, structure and socio-cultural environment also affect the child’s learning to speak.
Although the limits of normal language development are wide, they are usually children who do not speak at all even when they are 2 years old, and cannot make any sentences even when they are 4 years old. What worries the family is the experience of the previous child or the level of language development of other children around them.
In children with developmental language problems, it is often noticed that they can speak with few words, and their speech is partially or completely incomprehensible due to distorted pronunciation. Limited vocabulary in terms of content, sometimes associated with excessive use of slang and swear words.
For the diagnosis of developmental language disorder, the intelligence should be normal, the patient should not have been diagnosed with pervasive developmental disorder, no brain lesions should be shown, and there should be no hearing problems.
Although the limits of normal language development are quite wide, many children have learned all the features of their mother tongue by the age of 3-4. Children begin to understand before the age of 1, and to express after the age of 1. The average utterance length in children with language delay is shorter than in normal children. The child has no speech until 30-36 months and-or baby talk is seen. In other words, the language systems are not mature enough, for example, one-word sentences (holophrasia), repetitive speech, and the maintenance of a more dominant demand-need language is in question.
EARLY WARNING FINDINGS
Very Early Period
In children who will show normal language development, non-verbal communication is first supportive of verbal communication and then becomes more background as verbal language develops. This process is not observed in children whose language development will be impaired.
There are some early warning signs in children who will develop a developmental language problem. Gives variable or inconsistent responses to sounds. It has a response to sounds but is unresponsive to human voices. His interest in sounds may get worse over time, he cannot learn them. The sounds it makes are limited in terms of quality and quantity, or limited in pitch.
Cannot use sounds for language development. It does not make sounds that reflect different moods or does not react to such sounds. Does not follow sound stimuli, cannot make and maintain eye contact. Does not mutually vocalize adequately with his mother/caregiver, does not care about objects around him, does not imitate sounds and gestures, does not express anything with gestures and facial expressions, does not produce complex pre-speech sounds more and more frequently, more comfortably and with development.
In developmental language problems, other causes that may lead to other language problems must be excluded, as there are no definitive laboratory criteria for diagnosis. Among these, hearing problems, various articulation problems, psychosocial causes are the leading ones. Physical health problems accompanying developmental language problems are 2-3 times more common than normal. For example, asthma and allergies etc are more common.
Family history is also important. Among the close relatives in the family, the presence of delayed speech, attention and learning problems, people with tics, people who are overly meticulous, introverted and gifted are asked.
Major Types and Clinical Features of Developmental Language Disorders
In developmental language disorders, there is rarely a complete absence of language development, often delay or deviation. DSM-IV AND ICD-10 DA Some subtypes of developmental language disorders are selected. Although there are opposite views, the pure receptive type of developmental language disorder is rarely seen.
Receptive Language Disorder
Problems with understanding language can manifest themselves at a very early age. At the age of 1, there is a state of not reacting to familiar names, especially when there are no cues of non-verbal communication.
In the 18th month, there is an inability to recognize a few of the common objects, an inability to follow simple instructions at the age of 2, and then an inability to understand grammar items (such as negativity, comparison). These are often accompanied by an inability to understand the non-verbal aspects of language (tone of voice, gesture).
Children with severe inability to understand what is spoken may also fall behind in terms of social development, and they repeat the speech they do not understand in the style of echolalia. They often have limited interests. It cannot distinguish between active and passive sentences. Cannot distinguish prepositions according to verbal context. Children with receptive language problems often refer to the characteristics of the environment and context for understanding.
However, by the age of 2-3, they obey one-word stereoptic orders. Behavioral disorders are seen, cannot grasp grammatical structures such as negation or question suffixes.
Expressive Language Disorder
The common form of developmental language disorder is characterized by impairments in expressive language. People with expressive language disorder have delayed speech, poor vocabulary, lack of grammar, accompanying articulation defects, but very well preserved comprehension. There is a decrease in the ability to find words and in morphological diversity. He makes incomprehensible sentences due to both inflections and morphological problems. A few general words are overused. Short phrases are used. It has a simple sentence structure. There is difficulty in sequencing when describing past events. It generalizes grammatical rules excessively. Excessive use of gestures and facial expressions can attract attention. Expression flaw; It includes pronunciation problems, not remembering words (frequent use of “thing”), lack of words, inability to form sentences, lack of fluency (long intervals, interruptions), inability to initiate a speech spontaneously.
Phonological Type Disorder
Inadequate and faulty processing of native sounds in the brain while learning a language leads to impaired phonology and articulation in children. Speech problems are found in 10-15% of all children and 6% of school-age children, and most of them are phonological problems. The person’s vocal mechanism is sound, but he does not know how to arrange this mechanism phonetically. In the phonological problem, the wrong sound is chosen instead of the target sound and this is said. It cannot be determined at what time and where speech sounds will come in a word.
If the pronunciation disorder in the child’s speech has become permanent, if no words are understood even though he is 4 years old, it is necessary to worry again. These are collected in 4 groups; skipping errors where some sounds are missing (freeze), substitution errors (kipat instead of book), correct sound substitutions (/t/ instead of /k/), distortion errors where sounds are distorted (a sound is slightly different from what it should be / /g/ instead of k/) and addition (biskileyt) errors with additional sounds.
Phonological disorders are predominantly in consonants (it is very atypical to see vowel disorders and gives the impression that a foreigner is speaking). The same word can be said in different ways by changing the first letters (door-tap).
Mixed Type Disorder
There is a mixed type, in which the three types of clinical disorders mentioned above often coexist with varying severity and profile. In this form, the findings can be very variable and any of these three types of disorders predominately determines the clinical picture.
PROGRESSION IN DEVELOPMENTAL LANGUAGE DISORDER
Some of the children with developmental language problems overcome their problems, especially when they reach school age. 44% of children diagnosed with developmental language disorder at the age of 4 displayed normal abilities when they reached the age of 5.5. In most children with developmental language problems and improvement, the problems do not go away completely. Some subtle language problems in these children somehow remain. For example, while they are on the same level as their normally developing peers in terms of vocabulary and language comprehension, they lag behind in terms of phonological and academic abilities. Receptive developmental language disorder and speech delay resolve in a longer period.
Environmental factors also play an important role in the course of language development. The chirping period is adversely affected by various factors, such as middle ear problems, cerebral palsy, and the mother’s smoking during pregnancy. The amount and quality of communication that parents have with their children is also important. The fact that the child is scolded more quickly, the educational intervention is less in his language, and the use of less and less developed oral language in communication for the family also plays a negative role.
NEUROBIOLOGICAL BASIS OF DEVELOPMENTAL LANGUAGE DISORDER
Developmental language problems arise due to a brain pathology whose nature has not yet been determined.
While no major defect can be shown in the brain in developmental language disorders, microscopic structural changes and some volume changes can be shown, especially in the architecture of the cortex. Findings determined by imaging methods do not yet give fully consistent and satisfactory results. It is thought that the basis of developmental language problems is brain abnormalities such as changes in the size and number of neurons in the language and speech centers and the degree of myelination.
Autopsy examinations of the brain in developmental language problems have shown that the asymmetrical size of the sylvien fissure and planum temporale, which normally favors the left side of the brain, has disappeared. It is known that similar problems are common among the family and relatives of a child with developmental language problems.
Specialized Speech and Language Therapist