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Cited by 999Autism Spectrum Disorder ResearchAssistive Technology in Communication and MobilityChild Nutrition and Feeding Issues

Minimally Verbal School‐Aged Children with Autism Spectrum Disorder: The Neglected End of the Spectrum

Open access
Tager‐Flusberg, Helen, Kasari, Connie·2013·Autism Research
DOI 10.1002/aur.1329PMC PMC3869868
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Abstract

It is currently estimated that about 30% of children with autism spectrum disorder remain minimally verbal, even after receiving years of interventions and a range of educational opportunities. Very little is known about the individuals at this end of the autism spectrum, in part because this is a highly variable population with no single set of defining characteristics or patterns of skills or deficits, and in part because it is extremely challenging to provide reliable or valid assessments of their developmental functioning. In this paper, we summarize current knowledge based on research including minimally verbal children. We review promising new novel methods for assessing the verbal and nonverbal abilities of minimally verbal school‐aged children, including eye‐tracking and brain‐imaging methods that do not require overt responses. We then review what is known about interventions that may be effective in improving language and communication skills, including discussion of both nonaugmentative and augmentative methods. In the final section of the paper, we discuss the gaps in the literature and needs for future research. Autism Res 2013, 6: 468–478. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

Verified 2026-10-06 · 3 references not checked yet

Integrity signals

Registry

Crossref · 10.1002/aur.1329

Cites

59 of 62 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 60 cited sources checked · 0 supported · 0 flagged

  • Premisereasoning

    There is a dearth of valid, reliable, and appropriate means for direct assessment of minimally verbal children with autism spectrum disorder.

    “One significant barrier is the dearth of valid, reliable and appropriate means for direct assessments of this population.”
    Quote in the paperSubstantial claim
  • Interpretationreasoning

    It is often not possible to conduct direct assessments of minimally verbal children with autism spectrum disorder using currently available standardized tests.

    “For all these reasons it is often not possible to conduct direct assessments using currently available standardized tests”
    Quote in the paperSubstantial claim
  • Premisecitation

    Infants later diagnosed with autism who fail to acquire spoken language show significant delays in oral motor skills during the first year of life.

    “Retrospective parent report data suggest that infants who are later diagnosed with autism and fail to acquire spoken language show very significant delays in developing oral motor skills during the first year of life (Gernsbacher et al., 2008)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Gernsbacher et al., 2008

      Not checked in the free run.

  • Interpretationreasoning

    It is unlikely that the progress seen in the case study could be replicated across the majority of nonverbal individuals with autism spectrum disorder.

    “though some caution is warranted as it is unlikely that the same progress could be replicated across the majority of nonverbal individuals with ASD”
    Quote in the paperSubstantial claim
  • Premisecitation

    As nonverbal children with autism spectrum disorder get older, about 25% show increased social withdrawal on the social lethargy subscale of the Aberrant Behavior Checklist.

    “As these nonverbal children get older, about 25% begin to show more significant adverse consequences of having no means for communicating, with increased social withdrawal on the social lethargy subscale of the Aberrant Behavior Checklist (Lord, 2010)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lord, 2010

      Not checked in the free run.

  • Classified as probably not a substantial claim. 12
  • May combine two claims. 28
  • The quote only partly states this claim. 1

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Older statistics indicated that over half of all children with autism failed to acquire spoken language.

    “Older statistics suggest that over half of all children with autism failed to acquire spoken language (National Research Council, 2001)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites National Research Council, 2001

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Approximately 30% of children with autism spectrum disorder remain minimally verbal by school age, a lower proportion than older estimates of over half.

    “It is currently estimated that about 30% of children with autism spectrum disorder remain minimally verbal, even after receiving years of interventions and a range of educational opportunities.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Tager-Flusberg, Lord & Paul, 2005

      Not checked in the free run.

  • May combine two claims.

    Premisereasoning

    Eye-tracking, event-related potentials or electroencephalography, and magnetoencephalography are novel methods potentially available for assessing minimally verbal children with autism spectrum disorder, and most are still in development with reliability and validity being evaluated.

    “These include the use of eye-tracking measures (cf. Aslin, 2007; Aslin & McMurray, 2004), neurophysiological measures including event-related potentials (ERP) or electroencephalography (EEG; Choudhury & Benasich, 2011; Connolly et al., 2006), and magneto-encephalography (MEG; Imada et al., 2006), which are more feasible to implement than other brain imaging methods.”
    • Also stated in: § (2) Novel technologies for assessing receptive language and cognition · plain
      “At this point, most of these methods, which do not require the child to understand or follow even minimal instructions and do not require an overt motor response, are in the development phase for studies on minimally verbal children with ASD, with several research groups evaluating their reliability and validity.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Aslin, 2007

      Not checked in the free run.

    • cites Aslin & McMurray, 2004

      Not checked in the free run.

    • cites Imada et al., 2006

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Children with autism spectrum disorder who began speaking after age 5 seemed motivated to communicate orally and had received intensive, often behaviorally based, training in forming sounds and words.

    “All the successful children at these older ages seemed to be motivated to communicate orally, and had received intensive, often behaviorally based, training in the formation of sounds and words.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Pickett et al., 2009

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    For all the novel assessment technologies, children must receive training to tolerate the testing environment and minimize movement.

    “For all of them, children must receive training to tolerate the testing environment, and minimize movement.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The boys in that study learned to say and generalize set phrases, but there is no evidence they could spontaneously produce non-targeted words or phrases.

    “The boys in this study learned to say and generalize set phrases, such as, “Good morning” but there is no evidence they could spontaneously produce non-targeted words or phrases.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Charlop-Christy et al., 2002

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Children with autism spectrum disorder who began speaking after age 5 were more likely to have nonverbal IQ scores over 50 and had conceptual and semantic abilities that allowed them to map sounds to meaning.

    “These children had some conceptual and semantic abilities that allowed them to map sounds to meaning, and were more likely to have nonverbal IQ scores over 50.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Pickett et al., 2009

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The minimally verbal autism spectrum disorder population is highly variable, and no single explanation accounts for all such children.

    “this group of children is extremely variable and therefore no single explanation will account for all minimally verbal children”
    • Also stated in: § (1) Minimally verbal children with ASD · hedged
      “These examples of heterogeneity in cognitive and linguistic skills among minimally verbal children with ASD provide support for the view that no single underlying mechanism will explain why these children do not learn to speak.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In one single-subject multiple baseline study, two children over age 5 increased requesting with picture cues and also increased spontaneous production of spoken requests.

    “One exception is a study that used a single-subject multiple baseline design in which 2 of the 3 children were over age 5 (Charlop-Christy et al, 2002). Both the older children increased their use of requesting with the picture cues and also increased their spontaneous production of spoken requests.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Charlop-Christy et al, 2002

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Minimally verbal school-aged children with autism spectrum disorder vary in receptive language; some with minimal expressive language have good receptive language abilities, which correlate with their nonverbal abilities.

    “while some minimally verbal school aged children have low receptive and expressive language skills, other children with minimal expressive language scores have good receptive language abilities, which are correlated with their nonverbal abilities (Rapin et al., 2009)”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Rapin et al., 2009

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Premisenone given

    Most children with autism spectrum disorder beyond preschool age are not completely nonverbal; they often have some words or phrases that may or may not be used communicatively.

    “Most children beyond preschool age are not completely nonverbal; they often have some words or phrases that may or may not be used communicatively.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisereasoning

    In nearly all intervention studies, changes in communication were limited to the requesting function and increased responding, not spontaneous initiations.

    “Thus, in these studies changes in communication were limited to the requesting function and increased responding, not spontaneous initiations.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Among preschool children with autism spectrum disorder, about two-thirds to three-fourths will have some words, and at least half will use phrase speech by primary school.

    “estimates are that about two-thirds to three-fourths of all children will have some words, and that at least half will be able to use phrase speech by the time they enter primary school (Anderson et al, 2007; Magiati, Moss, Charman & Howlin, 2011; Turner, Stone, Pozdol, & Coonrod, 2006)”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Anderson et al, 2007

      Not checked in the free run.

    • cites Magiati, Moss, Charman & Howlin, 2011

      Not checked in the free run.

    • cites Turner, Stone, Pozdol, & Coonrod, 2006

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Magnetoencephalography provides the richest data on temporal and spatial processing from cortical systems and is well suited for single-subject data collection, but it is expensive and less developed for capturing specific stages of linguistic processing than event-related potentials.

    “While MEG provides the richest data on temporal and spatial processing from cortical systems and is well suited for single subject data collection, it is expensive and currently less well developed for capturing specific stages of linguistic processing than ERPs.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    For all these technologies, there is a trade-off between having a sufficiently large number of valid trials and the length of a testing session.

    “For all these technologies, there is a trade-off between having a sufficiently large number of valid trials (yielding usable, artifact-free data) and the length of a testing session.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In the only randomized clinical trial including children over age five, PECS training for teachers, parents, and staff led to higher rates of PECS-initiated communication but had no main effect on spoken language.

    “In the only randomized clinical trial (RCT) including children over age five, the effectiveness of PECS for 84 children was assessed (Howlin et al, 2007).”
    • Also stated in: § b) Interventions using augmentative and alternative communication (AAC) · plain
      “The main findings were that the children in classrooms whose teachers, parents and staff had received PECS training initiated communication at a higher rate using PECS, but there was no main effect on the use of spoken language.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Howlin et al, 2007

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Neurophysiological measures can distinguish between minimally verbal children who understand speech and those who do not, although not all participants with autism spectrum disorder provided sufficient artifact-free data for analysis.

    “These findings suggest that neurophysiological measures can distinguish between children who do understand speech from those who fail to, though it should be noted that not all participants with ASD were able to provide sufficient artifact-free data for analysis.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Intervention studies often exclude low-functioning potentially nonverbal children; comprehensive early intervention studies excluded children with developmental quotients or IQ scores below 35 or developmental ages below 12 months.

    “Intervention studies often exclude ‘low functioning’ potentially nonverbal children. For example, studies of comprehensive early interventions (e.g., Dawson et al, 2009; Lovaas, 1987) have excluded children with developmental quotients (or IQ scores) below 35 or developmental ages below 12 months.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Dawson et al, 2009

      Not checked in the free run.

    • cites Lovaas, 1987

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    A review identified 167 cases of children with autism spectrum disorder who started speaking after age 5, mostly between ages 5 and 7, with some starting up to age 13.

    “They surveyed the literature from 1951–2006 and identified 167 cases of children who started speaking after age 5. The majority began talking between the ages of 5 and 7, and some at even older ages, up to age 13.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Pickett et al., 2009

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Among children with autism spectrum disorder who began speaking after age 5, most increased their single-word utterances, but only about one-third moved into phrase speech.

    “While the majority of these children increased their single word utterances, only about one-third moved into phrase speech.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Pickett et al., 2009

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    PECS does not appear to inhibit the development of spoken language, but there is only limited evidence that PECS facilitates increased spoken language.

    “Thus, PECS does not appear to inhibit the development of spoken language, but there is only limited evidence that the use of PECS facilitates increased spoken language (Schlosser & Wendt, 2008).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Schlosser & Wendt, 2008

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Minimally verbal children with autism spectrum disorder vary in nonverbal IQ; some have low nonverbal IQ and others do not.

    “a recent large-scale study of preschoolers found that while some minimally verbal children have low nonverbal IQ, others do not (Munson et al., 2008)”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Munson et al., 2008

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Study design and conductnone given

    Methods must provide meaningful measures at the individual child level; this is currently more easily achieved for eye-tracking and magnetoencephalography than for event-related potentials, which relies mostly on group comparisons.

    “Methods must provide meaningful measures at the individual child level; this is currently more easily achieved for eye-tracking and MEG than for ERP, which relies mostly on group comparisons, averaging across participants.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Magnetoencephalography is expensive, not portable, generally unavailable outside major research centers, and most machines are built for adults and may require adaptation for younger children.

    “A MEG system is, however, far more expensive than EEG, not portable, and is generally not available outside major research centers. Most MEG machines are built for adult use, and may require adaptation for use with younger children (Imada et al., 2006).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Imada et al., 2006

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The children in that study had not responded to traditional behavioral treatments and had been labeled non-responders to other interventions.

    “These young children had failed to respond to traditional behavioral treatments, and had been considered “non-responders” to other interventions.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Koegel et al, (2009)

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Despite single-subject studies of successful use of AAC speech generating systems for increasing communication and spoken language in some individuals, researchers report very limited use of AAC devices in classrooms or at home.

    “Despite single subject studies of successful use of AAC speech generating systems for increasing communication and spoken language in some individuals (Schlosser & Wendt, 2008; Sigafoos et al, 2004), researchers report very limited use of AAC devices either in classrooms or at home (Brady, 2010).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Schlosser & Wendt, 2008

      Not checked in the free run.

    • cites Sigafoos et al, 2004

      Not checked in the free run.

    • cites Brady, 2010

      Not checked in the free run.

  • The quote only partly states this claim.

    Interpretationcitation

    Cueing the children's attention before giving the word prompt produced a significant increase in word production.

    “Thus, recruiting the children’s attention and then delivering the word prompt yielded significant improvement in producing words.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Most of these new technologies lack systematic curricula that could enhance their efficacy.

    “But little research has been conducted to evaluate these technologies, and most do not have systematic curricula associated with them that would potentially enhance their efficacy.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The joint attention and symbolic play interventions improved joint attention and play skills and predicted better expressive spoken language one year later.

    “The two experimental interventions (joint attention and symbolic play) not only yielded significant improvements in joint attention and play skills, they also predicted better expressive, spoken language one year later (Kasari et al, 2008).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Kasari et al, 2008

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Premisenone given

    Definitions of 'nonverbal' and pre-intervention assessments of child characteristics are heterogeneous.

    “One issue to tackle is the heterogeneity in the definitions of ‘nonverbal’ and in assessments of child characteristics prior to intervention.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Considerable progress has been made in understanding early predictors of language acquisition and in developing effective interventions for toddlers and preschoolers with ASD.

    “We have clearly made considerable progress in understanding early predictors of language acquisition and the development of effective interventions that target toddlers and preschoolers with ASD.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisenone given

    Participants in those older-child intervention studies have not been adequately characterized.

    “Intervention studies with older children have generally relied on case studies or single subject designs, and the participants enrolled in these studies have not been adequately characterized.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Little research has evaluated the new iPad and tablet applications for minimally verbal children.

    “But little research has been conducted to evaluate these technologies, and most do not have systematic curricula associated with them that would potentially enhance their efficacy.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisenone given

    Intervention studies with older children have mostly used case studies or single-subject designs.

    “Intervention studies with older children have generally relied on case studies or single subject designs, and the participants enrolled in these studies have not been adequately characterized.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisenone given

    Randomized controlled trials are rare in intervention research with older children.

    “Randomized controlled trials are rare.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Sherer and Schreibman found that the best PRT responders were children more engaged with objects, with some echolalia, more social approach, and less avoidance.

    “Sherer and Schreibman (2005) found that the best responders to PRT interventions were those children who were more engaged with objects, had some verbal behavior (echolalia), more social approach and less avoidance behavior.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Sherer and Schreibman (2005)

      Not checked in the free run.

36 of 36

  • The authors state this as an assumption.

    Eye-tracking measures assume that when a child hears a word, phrase, or sentence, the child will locate and look longer at an image matching the target language than at an unrelated image placed next to it.

    “the basic assumption of eye-tracking measures is that when a child hears a word, phrase or sentence, he or she will locate and then look longer at an image (picture, cartoon, or video) that matches the target language than at an unrelated image placed next to the matching image”

  • The authors state this as an assumption.

    If a child looks reliably longer at the matching image, it is assumed that the child understands the linguistic stimulus.

    “If a child looks reliably longer at the matching image (ensuring through counterbalanced presentation that the child does not show a significant bias to looking mostly at one side of the screen), then it is assumed that the child understands the linguistic stimulus.”

  • The paper relies on this without support.

    Useful speech by age 5 consistently predicts better social and adaptive functioning later in life.

    “Given the goal that “useful speech by age 5” consistently predicts better social and adaptive functioning later in life”

  • The paper relies on this without support.

    The developmental level of preschoolers with autism is similar enough to that of older minimally verbal children that adapting effective early interventions for older children could be beneficial.

    “The younger developmental age of preschoolers with autism may be commensurate with the skill levels of older minimally verbal children, such that adapting effective early interventions for older children may prove beneficial.”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Conflicting ages for participants in the same cited study

    Minor

    The paper describes the three children in Charlop-Christy et al. (2002) as all being 6-9 years old, but later says only two of the three were over age 5. Those age descriptions cannot both apply to the same three children.

  • Dawson study has conflicting publication years

    Minor

    The text cites Dawson et al. as a 2009 study, while its reference entry gives 2010.

2 of 2

Cites

Flagged first, then by citations

Research works printed but not linked: 4

  1. Brady N.(2010).AAC for children with autism. NIH Workshop on Nonverbal School‐Aged Children with Autism Bethesda MD April.
  2. Gordon B.(2010).What are the characteristics and predictors of school‐aged children who move from nonverbal to verbal?NIH Workshop on Nonverbal School‐Aged Children with Autism Bethesda MD April.
  3. Lord C.(2010).Who remains nonverbal? What do we know about these children and adults with ASD?NIH Workshop on Nonverbal School‐Aged Children with Autism Bethesda MD April.
  4. Schreibman L.(2010).Non‐augmentative interventions. NIH Workshop on Nonverbal School‐Aged Children with Autism Bethesda MD April.

Cited by

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Related

Authors
Tager‐Flusberg, H., & Kasari, C.
Affiliations
  • Department of Psychology Department of Anatomy and Neurobiology Boston University Boston Massachusetts
  • University of California, Los Angeles (US)
ORCID
Kasari, Connie
Venue
Autism Research
Publisher
Wiley
Published
2013-10-07
Volume
6
Issue
6
Pages
468-478
ISSN
  • 1939-3792 (ISSN-L)
  • 1939-3806
DOI
10.1002/aur.1329
PMC
PMC3869868
OpenAlex
W1909988460
Semantic Scholar
7e7bcb63fd020a7e8570c45984bfa8fc99834283
Cited by
985
References
60
Citations by year
2026: 159 · 2025: 112 · 2024: 95 · 2023: 96 · 2022: 93 · 2021: 81 · 2020: 92 · 2019: 83 · 2018: 67 · 2017: 35 · 2016: 36 · 2015: 23 · 2014: 9 · 2013: 1
FWCI
1.96
Type
journal article
Language
en
Open access
Licence
onlinelibrary.wiley.com/termsAndConditions#vor (vor)
Locations
  • Autism Research (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • National Institutes of Health (NIH) (NIDCD RO1 DC 10290-S1, P50 DC 13027, NIMH R01 MH084864)
  • Autism Speaks (2468)
  • Autism Speaks Hi Risk/Hi Impact (5666)
  • HRSA (UA3MC11055)
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Autism Spectrum Disorder Research
  • Health Sciences › Health Professions › Occupational Therapy › Assistive Technology in Communication and Mobility
  • Health Sciences › Medicine › Psychiatry and Mental health › Child Nutrition and Feeding Issues
Keywords
minimally verbal autism, autism spectrum disorder, school-aged children, language and communication skills, eye tracking, neuroimaging, augmentative and alternative communication, language intervention
MeSH terms
Brain, Child, Child Behavior, Child Development Disorders, Pervasive, Evoked Potentials, Eye Movements, Humans, Language Development Disorders, Nonverbal Communication, Verbal Behavior, Magnetoencephalography, Early Intervention, Educational

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