I. Definition of delayed speech and language development
Delayed speech and language development refers to children whose language development is not at an age-appropriate level during development, but does not include other types of language disorders such as hearing impairment and dysarthria. Most children with language delays have developmental delays or abnormalities in mental and peripheral responses. The main manifestations are language learning disorders, such as not speaking, only saying words, incoherent speech, and parroting when answering questions. Some children also have behavioral symptoms such as lack of eye contact with others, irritability, hyperactivity, and not playing with children.
Causes of delayed speech and language development
There are many causes of language delay, such as mental retardation, other sensory disorders, communication disorders, abnormalities of the phonological organs, and inappropriate language environment.
(A) Mental retardation
1. Mental retardation is a condition in which the overall intellectual function during development is significantly lower than the average level, resulting in or accompanied by adaptive behavior disorders, also known as mental retardation or mental retardation. Mental retardation belongs to people with intellectual disability and accounts for the largest proportion of speech delay.
2.Diagnostic criteria of mental retardation
(1) Low general intellectual function: the average intelligence quotient (intelligencequotient, IQ) is 100, and low intelligence IQ is more than two standard deviations below the normal level, i.e. IQ value is less than 70.
(2) Impaired social adaptation: The presence of impairments in adaptive behavior at a level appropriate to their age.
(3) Occurs during development: The developmental period refers to the period before the age of 18 years.
3.Verbal characteristics of mental retardation
The development of children’s language is closely related to their intellectual development. Children with mental retardation also have delayed language development, and the development of comprehension, expressive skills, and articulatory movements are all delayed compared to their actual age. In general, most children with mental retardation have more severe impairments in expressive language than in comprehension, and often by the age of 5 to 7, they can only express their thoughts with gestures or by nodding or shaking their heads. Children with mental retardation have difficulty understanding the connotations of words, so the transition from names to concepts is often difficult or takes a long time. In addition, children with mental retardation often have deficits in the movement of the phonological organs, which affects the accuracy of pronunciation.
(B) Other sensory disorders
1.Auditory disorders
The impact of auditory disorders on children’s language development is the most obvious. The impact of auditory disorders on language is mainly due to the impaired input of auditory language information, which leads to language impairment. Long-term language information input disorders, such as moderate or higher auditory disorders, affect the reception (comprehension) and, in turn, the emission (expression) of language information. The severity of language delay due to auditory impairment often parallels the degree of hearing impairment.
2.Visual impairment
Visual impairment mainly affects children’s linguistic ability in visual perception, visual association and visual memory, such as impairment in the use of nouns that indicate orientation and adjectives that indicate color in language.
(iii) Interaction disorders
1.Pervasive developmental disorder, also known as autism-like disorder, is a group of developmental disorders characterized by communication, language disorders and behavioral abnormalities, the most common ones are autism and Asperger’s syndrome.
Because of the lack of concern for the presence of verbal communication objects and the verbal stimuli themselves, the language development of children with autism is inevitably affected, with severe verbal and nonverbal communication deficits during the child’s language development. In terms of language symptoms, there are often delays in language development, grammatical errors and specific uses of language. The symptoms are often silent, language is not used to communicate with others, language with echo-like characteristics, self-talk that does not match the occasion, confusion in the use of personal pronouns, intonation without intonation, etc.
2, general emotional interaction disorder is also known as emotional disorder behavioral problems. It is generally considered to be a psychological problem arising from emotional deprivation or from the child’s own psychological problems. This part of the child’s growth process, due to a variety of social and emotional factors, resulting in psychological disorders such as attention deficit, hyperactivity disorder, conduct disorder, rebellious behavior problems, depression, muteness disorder, etc., can cause the individual’s language development disorder.
(iv) Inappropriate language environment
The lack of an appropriate language environment can affect the normal language development process. Children who are deprived or removed from their language environment early in their development can lead to language development disorders. During the critical period of language development, especially from 1 to 3 years old, children are in a multilingual environment, which is not conducive to the acquisition of their native language.
(E) Abnormalities of the phonological organs
Abnormalities of the phonological organs refer to motor disorders and structural abnormalities of the phonological organs, including pediatric cerebral palsy and cleft palate.
According to Chinese medicine, this disease is caused by the child’s congenital deficiencies and the lack of nourishment in later life. It is also pointed out that the symptoms of tardiness are “all fetal weakness”. The occurrence of delayed speech is related to the heart being the master of speech, the liver being the master of language, and the lungs being the master of sound.
The main manifestations of delayed speech and language development
Delayed language development is a state in which a child cannot demonstrate a linguistic knowledge system that is comparable to the expected normal standard. Clinically, children with language delay can be divided into simple language delay and combined language delay. Comorbid language delays often have other impairments, such as hearing and intellectual disabilities. Simple language delay has no abnormalities other than language impairment and is often overlooked. Delayed language development in children is mainly characterized by a late start, slow development and low level of development compared to normal children, and may include delays in speech expression, comprehension, communication and behavioral disorders.
(A) Speech and language disorders
Children with language delays are significantly behind normal children in their ability to use speech and oral expression. For example, they do not speak past the age of speech; after they begin to speak, their language expression develops more slowly than normal children or stagnates; although they can speak, their language skills are lower, and their vocabulary and grammar applications are lower than those of children of the same age. The screening criteria for language delay are: less than 30 vocabulary words at 24 months and less than 3 structural expressions at 30 months for boys and less than 5 for girls.
(ii) Language comprehension disorders
Language comprehension appears delayed to varying degrees, especially in children with mental retardation. Difficulties in language comprehension and following instructions may occur.
(C) Communication Disorders and Behavioral Abnormalities
Children with language delay, especially those with mental retardation, may have language learning and communication disorders, such as not being able to say sentences but only words, incoherent speech, slurred pronunciation, incomprehensible speech, and parrot-like behavior when answering questions. Due to communication disorders and psychological factors, children may be reluctant to communicate with others, lack of eye contact with others, irritability, hyperactivity, misbehavior, self-injury and injury.