Parent input predicts toddlers’ vocabulary development

This longitudinal study of 50 families and their typically-developing children examined how parent input effects child vocabulary scores one year later. Controlling for factors like the child’s prior vocabulary skill, quantity of input, and SES, they found that:

  • At age 1 ½, quantity of parent input most predicted later vocabulary.

    Note this doesn’t mean other things they didn’t measure couldn’t also impact it, like joint attention or parental responsivity

  • At age 2 ½, diversity of vocabulary in the input most predicted later vocabulary, even when controlling for input.

    Also, other research on children this age has found that vocabulary grows best when directed to the child, not via ambient conversation.

  • At age 3 ½, language complexity matters most

    e.g. decontextualized language like narratives, and explanations (such as answering “Why?” questions fully) 

And for an Early Intervention SLP, this all seems pretty logical. But transforming it into a simplified version for coaching parents could also be quite useful, such as saying:

  • For babies and one-year-olds, talk to your child, and focus on amount.

  • For two-year-olds, talk to your child, and focus on words.

  • For three-year-olds, talk to your child, and focus on sentences and stories.

… and then coaching what this would look like, specifically. Then, of course, the question becomes—would this be adequate, and would it make a difference? We don’t know. The next review (actually, the next two!) show research that digs in deeper to what’s needed for success.

 

Rowe, M.L. (2019). A longitudinal investigation of the role of quantity and quality of child-directed speech in vocabulary development. Child Development. doi: 10.1111/j.1467-8624.2012 

Let’s hear it for the verbs! Parents’ early verb use predicts children with ASD’s later verb vocabulary

2.png

Verbs are important for early language development; they are the building blocks for early sentences and help kids tell us about the things that are happening around them. But as we know, many of our children with ASD struggle to learn and use them flexibly. We know from the literature that for typically developing children, parents’ verb use can predict their later verb vocabulary. These researchers wanted to know if the same was true for children with ASD.

To do this, they measured the verbs that parents of children with ASD used during “follow-in utterances.” Follow-in utterances are comments that parents make during moments when they and their child are both focused on the same thing. So if a child knocked down a tower of blocks and looked up at his mom, her saying, “The tower crashed!” would be a follow-in utterance. The researchers looked at three aspects of parent verb use during follow-in utterances:

  1. The quantity of verb input, i.e., how often parents said verbs

  2. The diversity of verb input, i.e. how many different verbs parents said

  3. The grammatical informativeness of verb input, i.e. how much rich morphological information surrounded the verb. For example, “We’re jumping” would be more grammatically informative than “jump.” (See the article’s appendix for additional definitions and examples.)

They found that together, these three aspects of parent verb use during follow-in utterances predicted children with ASD’s later verb vocabulary. Because this is a correlational study (and doesn’t tell us what causes what), we’ll need further research to tell us if teaching parents to increase their quantity and quality of verb use will improve their children’s verb vocabulary. That being said, here are some ways authors describe that this line of research may impact what we teach parents:

  • We could teach parents to expand what their child says by adding a verb. For example, if the child says, “baby,” we could teach the parent to respond with, “the baby is sleeping,” rather than adding on to the noun phrase (e.g. “little baby”).

  • We could encourage parents to use diverse verbs during follow-in utterances, rather than over-relying on a small number of verbs and verb forms (such as “I want _____,” or “I need ______”).

  • We could teach parents to use grammatical language, rather than telegraphic. Because including grammatical morphemes seems to support children’s learning of verbs, we could teach parents to model fully grammatical language. For more research about using grammatical vs telegraphic language, see our previous review here.

 

Crandall, M.C., McDaniel, J., Watson, L.R., Yoder, P.J. (2019). The relation between early parent verb input and later expressive verb vocabulary in children with autism spectrum disorder. Journal of Speech, Language, and Hearing Research. doi:10.1044/2019_JSLHR-L-18-0081.

Input–output symmetry: why it matters for AAC users, and a word list to help

Child output = speech

Adult input = speech

Child output = AAC

Adult input = speech……. Whoops!? See how that might be a problem for learning?

How about:

Child output = AAC

Adult input = aided input (pointing to graphic symbols during speech)

“Among children with complex communication needs, vocabulary selection for aided AAC has almost exclusively been driven by consideration of expressive language needs. However, receptive language is critical to expres.png

No matter a child’s mode(s) of expressive communication, it’s our job to help ensure that they are getting receptive examples that match their expressive output, as often as possible. How? Encourage parents to use aided input, right? Simple!

Not simple. Consider this—are the words the family uses most frequently on the child’s device? Often times children’s AAC is programmed only for the child’s lexicon. But shouldn’t it also be set up for the words s/he is learning?

To help tackle the input–output asymmetry issue, this paper provides a list of words you may want to consider for programming young clients’ communication systems. The list is a compilation and comparison of data from three large sets, identifying words mothers use most frequently when speaking to their toddlers, as well as words most commonly spoken by toddlers and preschoolers.

They found that just over 250 words comprise most of mothers’ child-directed speech, with considerable overlap between mothers’ most frequent words and the words used by children (and this includes children unrelated to the mothers!… but arguably from similar cultural backgrounds). Another interesting finding: some mothers talk more than others (like, four times more), but the difference in lexical diversity among mothers (that is, number of different words) isn’t so high.

Though limitations include the fact that this research was done on typically-developing children, and it’s a new analysis of a ton of old data (from the late 80s forward), it “…provides a beginning place for guiding vocabulary selection.” So, basically, this list could be very useful as long as you take generational and cultural considerations in mind. So maybe add words like “tablet”? And please just ignore the fact that the data is on “mothers”, not parents in general—the world wasn’t as woke 20 years ago. 

This review is published in both the Early Intervention & Preschool & School-Age sections. 

Quick, N., Erickson, K., Mccright, J. (2019). The most frequently used words: Comparing child-directed speech and young children's speech to inform vocabulary selection for aided input. Augmentative and Alternative Communication. doi: 10.1080/07434618.201

Note: You can also find a link to this research at the author’s institutional repository, here.

Long-term outcomes of Hanen’s Target Word program

How much of a long-term impact does parent-implemented speech–language therapy have on late talkers? That’s an important question. Most studies have focused on short- or medium-term outcomes and have not looked into long-term follow-up results.

5.png

These researchers wanted to know the medium- and long-term effects of a low-dosage parent program for late talkers. To do this, they provided the Hanen’s Target Word program to 30 parents of 24-month-old late talkers, and followed a different set of 30 parents–child pairs that did not receive the program. The program included five group sessions and two individual video-feedback sessions over the span of three months. They then tested parents’ use of the strategies at 36 months, and language skills at 36 and 48 months.

They found that the program accelerated the vocabulary growth for the late talkers, but by age 4, there were no longer any differences between the two groups’ expressive vocabularies and both had reached age-appropriate scores. Both groups, however, continued to fall behind their peers in syntax and grammar.

The parents who participated in the study followed their child’s lead more and put less communicative pressure on their child; however, the parents did not significantly improve in how often they responded to their child’s communication or in how much linguistic stimulation they provided their child. Through analysis, the researchers found the strategy of reducing communicative pressure to be specifically associated with children’s language growth.

Here are some important considerations and takeaways from the study:

  • Null long-term results don’t mean that the intervention wasn’t worthwhile. As we know, increasing two year olds’ vocabularies can help ease the frustration of not being able to communicate which is an important goal of early intervention.

  • Dosage and coaching style play an important role in treatment outcomes. The authors discuss how the parent results of this study differed sharply from the Roberts and Kaiser (2015) study in which the researchers taught parents Enhanced Milieu Teaching (EMT) strategies, and parents were able to learn all of them. One of the reasons why is that the intervention dosage was much higher for the EMT study (four workshops and 24 hour-long sessions, compared to two), giving parents more opportunity for practice and feedback. Adjusting the dosage or coaching style of the Target Word program may be one option for increasing its long-term effectiveness.

  • Reducing communicative pressure may be an especially important strategy for parents. This is a simple strategy to teach parents, and these results demonstrate how powerful it can be for supporting language growth in toddlers.

  • Ongoing monitoring is important for late-talkers. Nearly one third of the children who participated still had language scores below the normal range at four years of age, but fewer than half of those children received speech–language therapy after the study. Monitoring is important to ensure that these children don’t fall through the cracks when language demands as they grow older.

One final note: this isn’t a replication study of Hanen’s Target Word program, but rather it’s a study that tested its effectiveness in real-world contexts. That’s awesome for two reasons: (1) authors aren’t tied to Hanen, which helps eliminate bias, and (2) real-world contexts = more like what we SLPs face = more clinically applicable! 

Want more? These authors also published a study of Hanen’s Target Word program (so popular!) This retrospective study (looking back at client charts) similarly showed gains in communicative participation and vocabulary for children who participated in the program.

 

Kruythoff-Broekman, A., Wiefferink, C., Rieffe, C., Uilenburg, N. (2019). Parent-implemented early language intervention programme for late talkers: parental communicative behaviour change and child language outcomes at 3 and 4 years of age. International Journal of Language & Communication Disorders. doi: 10.1111/1460-6984.12451

Go long! Go deep! Storybook reading intervention to target breadth and depth of word knowledge in preschool-age children

One of the most fun and, quite honestly, easiest contexts that we can use in therapy with toddlers and preschoolers is shared book reading. And, it’s kind of a no brainer that we can and should be using interactive read alouds to target one of the key areas of language development that’s lacking in our 2-, 3-, and 4-year-old clients: receptive and expressive vocabulary*.

In this intervention study of 226 preschoolers, they found that:

  • Kids who had a high initial level of vocabulary knowledge were able to increase their understanding and use of words through exposure alone.

  • However, for kids with the weakest initial vocabulary levels, exposure and repetition isn’t enough.

6.png

So what helps? Explicit instruction. Their explicit intervention activities included: pictures, clear child-friendly definitions, and being encouraged to act out, use, and explain target words. They found that in order to go beyond breadth (the number of words that you know) to depth (how much you know about a word), explicit instruction of word meaning and interactive activities that extend understanding beyond how the words are depicted in the book, helped. Ultimately, going long and going deep is key if we want to have a long-term impact on vocabulary development.

*This isn’t the first time we’ve discussed the topic of word learning during shared book reading. See this review, too.

 

Dickinson, D. K., Nesbitt, K. T., Collins, M. F., Hadley, E. B., Newman, K., Riveria, B. L., …Hirsh-Pasek, K. (2019). Teaching for breadth and depth of vocabulary knowledge: Learning from explicit and implicit instruction and the storybook texts. Early Childhood Research Quarterly. doi:10.1016/j.ecresq.2018.07.012