Late language emergence in toddlers is defined as language onset later than expected in children without any other disabilities (developmental or language specific) [1][2]. Late language emergence is seen as a more generalized term to describe a problem in first language acquisition on a normal schedule relatives to peer norms [3].

Not to be confused with Savant syndrome.

History

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Late Talking is sometimes called "Einstein syndrome." Einstein syndrome is a term coined by the economist Thomas Sowell to describe exceptionally bright people who experience a delay in development of speech [4]. Sowell claimed late talkers are often inaccurately categorized as having an autism spectrum disorder (ASD) and that a small subset of late talkers are actually highly intelligent children with common characteristics concentrated in music, memory, math or the sciences [4]. Einstein syndrome is named after Albert Einstein whom Sowell used as his primary example. Sowell also included Edward TellerSrinivasa Ramanujan, the mathematician Julia RobinsonRichard Feynman, and the pianists Clara Schumann and Arthur Rubinstein to be in this group[4].

Prevalence & Predictors

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Prevalence among toddlers who experience late talking (identified as late language emergence) was as high as 13.4% in one epidemiological study of 24-month old children, meaning that 13.4% of the children in the study were at least one standard deviation below the mean for their age [1]. Maternal factors of age at child's birth, education, birthplace, employment, cigarette use, depression levels, anxiety, and stress are not significant and therefore do not play a role in a child becoming a late talker [1]. Children with late talking (late language emergence) were found to be more prominently male (3x more likely then females) and with a history of late talking in the family [1]. Late talkers are also more likely to have siblings rather than be only children[1]. Infants who were 85% or less of their optimal birth weight or born prematurely (before 37 weeks gestation) were at a risk of two times more likely to develop late language emergence than others in the study by Zubrick et al. (2007) [1].

In a different study by Rice et al. (2014) found that late talking is genetically linked through a twin study[5]. Traits such as vocabulary estimate, words produced, grammar estimate, and mini-finiteness were all analyzed and found to be significant and therefore are heritable traits[5].

Outcomes depend on a few different predictors. For the most part, if a child has no primary diagnosis (such as ASD, general intellectual disability, or a vocal tract malformation), outcomes tend to normalize to other peer groups within 6-7 years of age [2].

Vocabulary of Late Talkers

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A study by MacRoy-Higgins et al. (2016) looked at toddlers who were late talkers compared to both age-matched (AM) peers and vocabulary matched (VM) peers[6]. The semantic categories, or the types of words, that late talkers use are both similar and different from both AM and VM groups. Similarities included the categories of food and drink being highly used in all three groups of toddlers[6]. A major difference between the late talkers and the AM and VM groups is that late talkers utter abundantly more words classified as 'animal sounds/effects', while the AM and VM groups overwhelmingly had the largest percentage in the 'animal' classification[6]. Additionally, late talkers had fewer nouns in their vocabulary than both the VM and AM group[6].

Typical Language Development

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Zero to Twelve Months

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Language Development starts as soon as a baby is born. Around three to four months, a child will start with small utterances that sound like gurgles and slight coos to the parents[7]. By about seven months, children start to string together a vowel and consonant sound that is mostly widely known as babbling [7]. Although children are still technically in the "prelinguistic" stage before 12 months, infants are able to make wants and needs known to parents through pointing and small utterances called "proto-declaratives" starting around ten months of age [7].

Twelve to Twenty-four Months

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The first fifty words that infants learn are integrated into their vocabulary by around a year and a half, or 16 months. After hitting 50 words, children's vocabulary sky rocket exponentially with something called the "naming explosion" [7]. Typical language development sees about nine words learned a day from 16 to 24 months of age, with the first combination of words appearing around this time too [3][7].

Twenty-four to Thirty-six Months

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This period is typically defined by grammatical development and refinement. The first half of this third year, children will start adding a verb to a noun (eg "daddy run" or "eat dinner"), while the second half of the year will see a more sophisticated grammar mastery with the child now using tenses to their verbs (eg "running" and "walked") [3][7].

Language Assessments

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Language can be boiled down to a combination of two components: expressive and receptive language functions [8]. Most clinical language assessments will include basic aspects of the following[8]:

While a young child such as a two or three year old late talker does not have the skills yet for reading, writing or a few other more mature items on the list, it is necessary for a professional to make assessments for language delays because a delay could mean a variety of outcomes for a child from a variety of reasons. If a child is not at the typical 50 word marker by 16 months, it is best to ask the pediatrician if a language assessment is needed. The best indicator of a late talker just having delayed speech output and not a different language impairment is when looking at the receptive language skills [8]. Asking a child to 'pick up the red shoe and put it in the circle ' is an example of a task meant to test receptive language skills. A delay in the expressive language is one of the most common reasons children are referred for further language assessments[2].

  1. ^ a b c d e f Zubrick, Taylor, Rice & Slegers (2007). "Late language emergence at 24 months: an epidemiological study of prevalence, predictors, and covariates". Journal of Speech, Language, and Hearing Research. 50: 1562–1592.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ a b c Rescorla, Leslie (2011). "Late Talkers: Do Good Predictors of Outcome Exist". Developmental Disabilities. 17: 141–150.
  3. ^ a b c Villiers & Davidson (2011). "Language Delay". The Gale Encyclopedia of Chldren's Health: Infancy through Adolescence. 3: 1303–1306.
  4. ^ a b c Sowell, Thomas (1997). Late Talking Children. New York, NY: Basic Books.
  5. ^ a b Rice, Zubrick, Taylor, Gayan, & Bontempo (June 2014). "Late Language Emergence in 24-Month-Old Twins: Heritable and Increased Risk for Late Language Emergence in Twins". Journal of Speech, Language, and Hearing Research. 57: 917–928.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  6. ^ a b c d MacRoy-Higgins, Shafer, Fahey, & Kaden (2016). "Vocabulary of Toddlers Who Are Late Talkers". Journal of Early Intervention. 38: 118–129.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. ^ a b c d e f Salkind, Neil J. (2002). Child Development; The Macmillan Psychology Reference Series. New York, NY: Macmillan Library Reference USA. pp. 228–232. ISBN 0-02-865618-0.
  8. ^ a b c Schoenberg & Scott (2011). The Little Black Book of Neuropsychology. New York, NY: Springer. pp. 159–178. ISBN 978-1-4899-7755-7.