|This article needs additional citations for verification. (March 2008) (Learn how and when to remove this template message)|
Language delay is a failure in children to develop language abilities on the usual age appropriate for their developmental timetable. Language delay is distinct from speech delay, in which the speech mechanism itself is the focus of delay.
Oral communication is a two-stage process. The first stage is to encode the message into a set of words and sentence structures that convey the required meaning, i.e. into language. In the second stage, language is translated into motor commands that control the articulators (organs and structures such as the lungs, vocal cords, mouth, tongue, teeth, etc.), thereby creating speech, i.e. orally-expressed language.
Because language and speech are independent, they may be individually delayed. For example, a child may be delayed in speech (i.e., unable to produce intelligible speech sounds), but not delayed in language. However a child with a language delay typically has not yet been able to use language to formulate material to speak; he or she is therefore likely to have a delay in speech as well.
Language delay is commonly divided into receptive and expressive categories. Receptive language refers to the process of understanding what is said to the subject. Expressive language refers to the use of words and sentences to communicate messages to others. Both categories are essential to effective communication.
Language delay is a risk factor for other types of developmental delay, including social, emotional, and cognitive delay. Some children may grow out of these deficits, even coming to excel where they once lagged, while others do not. One particularly common result of language delay is delayed or inadequate acquisition of reading skills. Reading depends upon an ability to code and decode script (i.e., match speech sounds with symbols, and vice versa). If a child is still struggling to master language and speech, it is very difficult to learn another level of complexity (writing). Thus, it is crucial that children have facility with language to be successful readers.
Neuroscientist Steven Pinker postulates that a certain form of language delay may be associated with exceptional and innate analytical prowess in some individuals, such as Albert Einstein, Richard Feynman and Edward Teller.
Language delays are the most frequent developmental delays, and can occur for many reasons. A delay can be due to being a “late bloomer,” or a more serious problem. The most common causes of speech delay include
- Hearing loss
- Slow development
- Intellectual Disability
Such delays can occur in conjunction with a lack of mirroring of facial responses, unresponsiveness or unawareness of certain noises, a lack of interest in playing with other children or toys, or no pain response to stimuli.
Other causes include:
- Psychosocial deprivation - The child doesn't spend enough time talking with adults. Research on early brain development shows that babies and toddlers have a critical need for direct interactions with parents and other significant care givers for healthy brain growth and the development of appropriate social, emotional, and cognitive skills.
- Television viewing is associated with delayed language development. Children who watched television alone were 8.47 times more likely to have language delay when compared to children who interacted with their caregivers during television viewing. As recommended by the American Academy of Pediatrics (AAP), children under the age of 2 should watch no television at all, and after age 2 watch no more than one to two hours of quality programming a day. Therefore, exposing such young children to television programs should be discouraged. Parents should engage children in more conversational activities to avoid television-related delays to their children language development, which could impair their intellectual performance.
- Stress during pregnancy is associated with language delay.
- Being a twin
- Autism (a developmental disorder) - There is strong evidence that autism and ADHD are also commonly associated with language delay. Asperger syndrome, which is on the autistic spectrum, however, is not associated with language delay.
- Selective mutism (the child just doesn't want to talk)
- Cerebral palsy (a movement disorder caused by brain damage)
- Genetic abnormalities - In 2005, researchers found a connection between expressive language delay and a genetic abnormality: a duplicate set of the same genes that are missing in sufferers of Williams-Beuren syndrome. Also so called XYY syndrome can often cause speech delay. 
- Correlation between male sex, previous family history and maternal education has been demonstrated.
Studies have failed to find clear evidence that language delay can be prevented by training or educating health care professionals in the subject. Overall, some of the reviews show positive results regarding interventions in language delay, but are not curative. (Commentary - Early Identification of Language Delays, 2005)
- Auditory processing disorder
- Cleft palate
- Down syndrome
- Developmental verbal dyspraxia
- Speech therapy
- Speech production (vocalization)
- Pinker, Steven (24 June 1999). "His Brain Measured Up". The New York Times. Retrieved 2006-12-04.
- "Language Learning Styles". TLG. August 2013. Retrieved 22 August 2013.
- "Frequently Asked Questions". American Academy of Children & Adolescent Psychiatry. Retrieved 22 August 2013.
- Committee on Public Education (August 1999). "Media education". Pediatrics. 104 (2 Pt 1): 341–3. doi:10.1542/peds.104.2.341. PMID 10429023.
- Chonchaiya, W; Pruksananonda, C (July 2008). "Television viewing associates with delayed language development". Acta Paediatrica. 97 (7): 977–82. doi:10.1111/j.1651-2227.2008.00831.x. PMID 18460044.
- Talge, NM; Neal, C; Glover, V (2007). "Antenatal maternal stress and long-term effects on child neurodevelopment: how and why?". Journal of Child Psychology and Psychiatry. 48 (3-4): 245–61. doi:10.1111/j.1469-7610.2006.01714.x. PMID 17355398.
- Miniscalco, C; Nygren, G; Hagberg, B; Kadesjö, B; Gillberg, C (May 2006). "Neuropsychiatric and neurodevelopmental outcome of children at age 6 and 7 years who screened positive for language problems at 30 months". Developmental Medicine & Child Neurology. 48 (5): 361–6. doi:10.1017/S0012162206000788. PMID 16608544.
- Hagberg BS, Miniscalco C, Gillberg C (2010). "Clinic attenders with autism or attention-deficit/hyperactivity disorder: cognitive profile at school age and its relationship to preschool indicators of language delay". Research in Developmental Disabilities. 31 (1): 1–8. doi:10.1016/j.ridd.2009.07.012. PMID 19713073.
- American Psychiatric Association (2000). "Diagnostic criteria for 299.00 Autistic Disorder". Diagnostic and statistical manual of mental disorders: DSM-IV (4 ed.). Washington, DC: American Psychiatric Association. ISBN 0-89042-025-4. OCLC 768475353.
- Campbell, T F; Dollaghan, C A; Rockette, H E; Paradise, J L; Feldman, H M; Shriberg, L D; Sabo, D L; Kurs-Lasky, M (2002). "Risk factors for speech delay of unknown origin in 3-year-old children" (PDF). Child Development. 74 (2): 346–57. PMID 12705559.
- Speech Therapy for Down Syndrome
- Different Issues in Speech and Language Development - American Speech-Language-Hearing Association (ASHA)
- Delay in Speech and Language - KidsHealth
- Early Identification of Speech-Language Delays and Disorders
- Speech and Language Delays and Disorders - University of Michigan Health System
- Wilson, Philip; McQuaige, Fiona; Thompson, Lucy; McConnachie, Alex (2013). "Language Delay Is Not Predictable from Available Risk Factors". The Scientific World Journal. 2013: 1–8. doi:10.1155/2013/947018.
- CHAPTER III - Assessment Methods for Young Children With Communications Disorders