Pragmatic Language and its relation to Executive Functioning, Adaptive Functioning and Attention-Deficit/Hyperactivity Disorder in Children with

Autism Spectrum Disorder

By Kellie Ileto

B.A. in Psychology, May 2010, University of Rochester

A Thesis submitted to

The Faculty of The Columbian College of Arts and Sciences

of the George Washington University in partial fulfillment of the requirements

for the degree of Master of Arts

May 15, 2016

Thesis directed by

Gregory L. Wallace Assistant Professor of Speech and Hearing Sciences

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Dedication The author wishes to “dedicate this Masters Thesis to Lillie Coker who dedicated

her life to educating others and inspired me to never stop learning, growing and

helping those in need.”

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Acknowledgements

The author wishes to “acknowledge the Speech and Hearing Department of the

George Washington University for giving me the opportunity to be part of this

incredible community, for supporting and guiding me throughout my graduate

school career and for providing me with the knowledge to be successful in this

field.”

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Abstract

Pragmatic Language and its relation to Executive Functioning, Adaptive Functioning and Attention-Deficit/Hyperactivity Disorder in Children with

Autism Spectrum Disorder Pragmatic language difficulties are commonly documented in individuals with

autism spectrum disorder; however, little research exists that looks at pragmatic

language in relation to executive functioning, adaptive functioning, and attention

deficit hyperactivity disorder (ADHD) symptoms in this population. The current

study had two aims: (1) determine the structural and pragmatic language profile

of relative strengths and weaknesses among individuals with autism spectrum

disorder using the Children’s Communication Checklist-2 (CCC-2) and (2)

examine relationships between pragmatic language as measured by the CCC-2

and the following; executive functioning as measured by the Behavior Rating

Inventory of Executive Function, adaptive functioning as measured by the

Vineland Adaptive Behavior Scales, and ADHD symptomatology as measured

by the ADHD Rating Scale. Results revealed a relative strength in structural

language and a relative weakness in pragmatic language among individuals with

autism spectrum disorder on the CCC-2. Furthermore, results showed pragmatic

language to be associated with aspects of executive functioning, adaptive

functioning, and ADHD symptomatology. This relationship suggests that

treatment of executive functioning or adaptive functioning could result in

positive outcomes in ameliorating pragmatic language deficits (or vice versa) in

individuals with autism spectrum disorder.

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Table of Contents Dedication ………………………………………………………………….………...….ii

Acknowledgements ……………………………………………………………….......iii Abstract …………………………………………………………………………………iv List of Tables ……………………………………………………………………….......vi Chapter 1: Introduction …………………………………………………………….…..1 Chapter 2: Methods ......………………………………………………………….........12 Chapter 3: Results ……………………………………………………………..............17 Chapter 4: Discussion ……………………………………………………………........20 Chapter 5: Conclusions/Future Research …………………………………………..25

References .......................................................................................................................26

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List of Tables

Table 1 ............................................................................................................................. 13

Table 2 ............................................................................................................................. 17

Table 3 ............................................................................................................................. 18

Table 4 ............................................................................................................................. 19

Table 5 ............................................................................................................................. 19

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Introduction Pragmatics:

Pragmatic language impairment exists when there is a mismatch between

language and the situation in which it is used resulting in an inappropriate

employment of language to a particular situation (Volden & Lord, 1991).

Pragmatics is an aspect of language necessary for communication and interaction

with others allowing for full participation within the community and navigating

the social world. It involves the range of communicative functions (reasons for

talking); the frequency of communication (turn-taking, topic maintenance and

change, requests for clarification); the flexibility to modify language for different

listeners and social situations; and the ability to convey a coherent and

informative narrative (Paul & Norbury, 2012). Pragmatic language impairments

can be expressed in the context of a variety of psychiatric disorders or

neurological insults, including but not limited to schizophrenia (Mueser, Bellack,

Douglas & Morrison, 1991), social phobia (Beidel et al., 2014), attention-

deficit/hyperactivity disorder (ADHD) (Nijmeijer et al., 2008), traumatic brain

injury (Douglas, 2010), and right hemisphere damage (Martin & McDonald,

2003). However, pragmatic language difficulties are perhaps most commonly

associated with autism spectrum disorder (ASD; Landa, 2000; Tager-Flusberg et

al., 2005; Young, Diehl, Morris, Hyman & Bennetto, 2005). Individuals with

higher functioning ASD (HF-ASD) often perform in the average to superior

range on standardized (particularly structural) language measures with

pragmatics often being the only area of deficit (Reichow, Salamack, Paul,

2

Volkmar & Klin, 2008). The Diagnostic and Statistical Manual of Mental

Disorders-5th Edition (DSM-5; APA, 2013) states that individuals with ASD have

persistent deficits in social communication and social interaction across multiple

contexts. For example, there are deficits that include difficulties with the back-

and-forth inherent to conversational discourse, failure to initiate or respond to

social interactions, poor nonverbal communication such as eye contact and body

language, and difficulty with developing, maintaining and understanding

relationships (APA, 2013). There is a large amount of evidence for pragmatic

language difficulties in ASD. In their review of the literature, Martin and

McDonald (2003) documented these difficulties in ASD as well as other clinical

groups (e.g., right-hemisphere damage and traumatic brain injury). They found

evidence for pragmatic language difficulties in ASD that included overly literal

language comprehension (Baron-Cohen, 1997; Happé & Frith, 1996; Happé,

1993), difficulty understanding humor (Ozonoff & Miller, 1996), socially

inappropriate and disinhibited comments (Dewey & Everard, 1974; Tsai & Scott-

Miller, 1988), conversations characterized by tangents and excessive talking

(Attwood, 1997; Szatmari, Bartolucci, & Bremner, 1989), formal pedantic

language (Ghaziuddin & Gerstein, 1996; Kerbeshian, Burd, & Fisher, 1990), poor

verbal fluency and inefficiency conveying information (Szatmari et al., 1989),

prosody impairments (Happé & Frith, 1996; Shriberg et al., 2001), and difficulty

reading emotion and facial expression (Happé & Frith, 1996; Ozonoff,

Pennington, & Rogers, 1990; Prior, Dahlstrom, & Squires, 1990).

3

Tools for measuring pragmatic abilities, valid norms for pragmatic

language development, and objective criteria for pragmatic performance are

relatively (compared to structural language measures) limited (Young et al.,

2005). As a result, various approaches have been used to measure pragmatics

such as informant (e.g., parent, teacher, self) report questionnaires, naturalistic or

lab-based observations, and standardized laboratory measures such as the Test of

Pragmatic Language (TOPL – Phelps-Terasaki & Phelps-Gunn, 1992). Perhaps the

most commonly utilized tool is the Children’s Communication Checklist (CCC;

Bishop, 1998) and its derivations (i.e., CCC-2 (Bishop, 2003), Communication

Checklist – Adult (CC-A) (Whitehouse & Bishop, 2009) which have been proven

effective in documenting pragmatic language deficits in a variety of clinical

populations (Geurts et al., 2004; Bishop & Baird, 2001; Nathan, 2002; Botting,

2004; Bishop, 2010; Philofsky, Filder & Hepburn, 2007; Whitehouse, Coon, Miller,

Salisbury, & Bishop, 2010). By documenting pragmatic language difficulties in

clinical groups known to have these impairments these findings support the

validity of these questionnaire-based assessment tools. Moreover, individuals

with ASD tend to be the most pragmatically impaired compared to other clinical

groups on this measure (Botting, 2004). Finally, Bishop’s revised version of the

checklist, the CCC-2 (Bishop, 2003) has also been shown to differentiate between

pragmatic language impairments and structural language impairments in ASD

(i.e., relatively superior structural language) and specific language impairment

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(SLI; relatively superior pragmatic language) (Norbury, Nash, Baird, & Bishop,

2004).

The CCC-2 has also been shown to be more effective than other

assessment measures for pragmatics. Volden and Phillips (2010) administered

the TOPL to participants with ASD and matched typically developing peers and

gave the CCC-2 to the participants’ caregivers. Results showed that the TOPL

identified 56% of the ASD participants as being pragmatically impaired while the

CCC-2 identified 82% of the ASD participants as being pragmatically impaired. It

was concluded that the CCC-2 (compared to the TOPL) had better sensitivity in

identifying pragmatic issues among children with ASD who also had age

appropriate structural language skills. The CCC-2 has also been shown to be

effective as a screening tool for ASD and the broader autism phenotype in

typically developing siblings of children with ASD (Bishop et al., 2006; Charman

et al., 2007). The CC-A (Whitehouse et al., 2010) also serves as an informant rated

assessment tool of language and communication skills but unlike the CCC-2, it is

tailored to the adult population. Whitehouse et al. (2010) found the CC-A to be

effective in identifying communicative dysfunction in ASD probands as well as

their parents.

Although there is now well-established research documenting pragmatic

language impairments in ASD, how these impairments relate to other important

domains of functioning (e.g., executive and adaptive functioning) in ASD

remains largely unexplored.

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Executive Functioning:

Executive functioning (EF) involves cognitive control processes that

include inhibition of actions, restraining and delaying responses, attending

selectively, setting goals, planning and organizing, generativity, flexibility and

working memory (Singer & Bashir, 1999; Barkley, 1997; Eslinger & Biddle, 2000;

Pennington, Bennetto, McAleer, & Roberts, 1996; Bishop & Norbury, 2005; Landa

& Goldberg, 2005). Executive dysfunction therefore can hinder an individual’s

ability to fully function in a world where higher thinking processes are

necessary. The majority of research assessing EF in ASD involves lab tasks such

as the Wisconsin Card Sorting Test assessing cognitive flexibility and tower tasks

(e.g., the Tower of London) measuring multiple EF demands, including

planning. EF is important in ASD because it is associated with adaptive

functioning and ASD symptomatology (Liss et al., 2001; Pugliese et al., 2015). In

ASD these EF tasks have provided mixed results with some revealing ASD

deficits while others do not (Kenworthy, Yerys, Anthony & Wallace, 2008; Hill,

2004). Recently, ecologically valid assessments have been used to assess EF in

ASD with more consistently documented deficits emerging (Kenworthy et al.,

2008). Ecological validity is defined as the degree to which task performance

corresponds to real-world performance with particular emphasis on the

inferences drawn from the task performance as opposed to the task itself

(Chaytor, Schmitter-Edgecombe, & Burr, 2006). An example of an ecologically

valid assessment of EF includes the Behavioral Assessment of the Dysexecutive

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Syndrome (BADS) which contains six measures to assess planning, organization,

shifting, inhibition, novel problem solving, and temporal judgment by requiring

the subject to engage in familiar everyday activities such as searching for lost

keys (Wilson, Alderman, Burgess, Emslie, & Evans, 1996). Another ecologically

valid way to assess EF is to use informant reports such as the Behavior Rating

Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000)

which assesses everyday executive control and produces eight non-overlapping

clinical scales, including Inhibit, Shift, Emotional Control, Monitor, Working

Memory, Plan/Organize, Organization of Materials, and Initiate (Gioia et al.,

2000). To date, research using the BRIEF to assess EF in ASD finds global EF

deficits in ASD (Granader et al., 2014; Rosenthal et al., 2013; Chan et al., 2009)

with a peak EF problem in flexibility (on the Shift scale). Granader et al. (2014)

examined results from parent-completed BRIEFs among 411 children with ASD

and 467 age and sex matched typically developing children. They found elevated

scores (indicative of more EF problems) in the ASD group across all BRIEF scales

with the most prominent deficit on the Shift (i.e., flexibility) scale. Similarly,

Rosenthal et al. (2013) compared different age groups of children with ASD on

EF measures finding that older children with ASD exhibited more EF problems

(i.e., with increasing age there were increasing working memory difficulties)

relative to the BRIEF standardization sample as well as a developmentally

invariant peak impairment in flexibility (Shift scale scores).

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Whether pragmatic language skills are associated with impairments in EF

in ASD however remains unclear. Pragmatic language skills could regulate

responses that are appropriate to the context by inhibiting inappropriate

responses, using working memory to remember what has been said in order to

respond appropriately, attending to the message as well as the non-verbal

behavior of the speaker (e.g. prosody, gestures) and organizing and planning

one’s response. Research has shown that pragmatic language skills are related to

working memory deficits (Akbar, Loomis, & Paul, 2007; Freed, Lockton, &

Adams, 2012). Executive dysfunction could therefore result in poor pragmatic

language skills. Bishop and Norbury (2005) looked at children with HF-ASD,

Specific Language Impairment, Pragmatic Language Impairment and a group of

(age, gender, and non-verbal ability) matched typically developing peers and

found significant correlations between pragmatics and the EF domain of

generativity. In other words, children with impaired pragmatics also often

showed poor generativity skills. They concluded that these children have poor

skills in generating ideas relevant to the context. Overall, there is limited research

that explores the relationship between EF and pragmatic language in ASD.

Adaptive Functioning:

Adaptive functioning can be thought of as an individual’s ability to

function in the natural social environment across a multidimensional set of skills

(Oswald & DiSalvo, 2003). The presence of social and communication deficits in

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individuals with ASD negatively impacts these adaptive functioning skills

making it difficult for an individual with ASD to function independently in

everyday situations. Adaptive skills are considered one of the most important

outcome measures in ASD because they measure one’s success in navigating

society’s many everyday challenges (Williams, Mazefsky, Walker, Minshew, &

Goldstein, 2014). Nevertheless, how well pragmatic language impairments

predict adaptive skills in ASD remains largely unknown (Volden et al., 2009).

One study has used standard lab tasks of pragmatic language in order to

examine its association with adaptive functioning. Volden et al. (2009) assessed

pragmatic language using the TOPL in 37 children with HF-ASD and

investigated its correlations with scores from the Vineland Adaptive Behavior

Scale (VABS; Sparrow et al. 1984), the most commonly utilized tool for assessing

adaptive functioning. This study found that pragmatic language scores did not

predict adaptive functioning suggesting the need to utilize a more sensitive

measure of pragmatic language skills as observed in everyday settings (e.g., the

CCC-2) in future studies.

Co-morbidity with Attention-Deficit/Hyperactivity Disorder (ADHD):

ADHD is a persistent pattern of inattention and/or hyperactivity-

impulsivity that interferes with functioning or development characterized by

wandering off task, difficulty sustaining attention, inability to delay gratification

and desiring immediate rewards (APA, 2013). Several forms of psychopathology

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are highly comorbid with ASD with ADHD being one of the most common

(Keen & Ward, 2004; Simonoff et al., 2008; Leyfer et al., 2006). Similar to ASD,

ADHD is also associated with pragmatic language difficulties (Geurts &

Embrechts, 2008). For example: 1) excessive talking during times that one should

be listening; 2) difficultly producing organized and fluent speech for specific

purposes when elicited rather than during spontaneous conversation; 3)

dominating conversations and not responding appropriately to verbal cues from

conversational partners; and 4) possible difficulty with higher level language

comprehension especially for inferences and story elements (Green, Johnson &

Bretherton., 2014). Geurts and Embrechts (2008) examined language profiles

using the CCC-2 in ASD, SLI, ADHD, and typically developing matched peers

and found that both ASD and ADHD groups showed more difficulty with

pragmatic language than structural language. In addition, they found that the

added presence of impulsivity, a behavior characteristic of ADHD, as measured

by the Preschool Behavior Questionnaire (PBQ; Smidts & Oosterlaan, 2005), in

the ASD and SLI groups was associated with greater structural and pragmatic

language difficulties. Timler (2014) also found that the CCC-2 could be used as a

screener to identify children with ADHD who are at elevated risk for language

impairment. The DSM-5, unlike its predecessor, the DSM-IV, allows co-morbid

diagnoses of ASD and ADHD. Given that prior studies have found that the

presence of ADHD symptoms in ASD exacerbated deficits in EF, particularly

working memory, and adaptive functioning (Yerys et al., 2009), how this

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comorbidity could affect pragmatic language skills is of particular importance as

it might represent a ‘double hit’ or additive model of pragmatic language

deficits.

Research Aims:

Pragmatic language is a nearly universally impaired domain of

functioning in individuals with ASD (Landa, 2000, Tager-Flusberg et al., 2005;

Young et al., 2005). Pragmatic language deficits are likely associated with both

adaptive functioning and EF in ASD. Therefore, these relationships were

examined empirically by examining links between pragmatic language skills as

measured by the Children’s Communication Checklist - 2 (CCC-2) and both

adaptive functioning deficits as measured by the Vineland Adaptive Behavior

Scale and real-world EF utilizing the BRIEF after accounting for nuisance factors

such as age, IQ (as measured by the Wechsler Scales), and structural language

abilities (also measured with the CCC-2). Furthermore, the presence of comorbid

ADHD symptomatology in ASD was examined to determine whether it

exacerbates pragmatic language deficits given that each of these disorders

independently exhibits pragmatic language problems.

Variables:

Independent Variables: The independent variable in this study is pragmatic

language functioning as measured by the CCC-2.

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Dependent Variables: The dependent variables in this study include:

1. Executive functioning as measured by the BRIEF

2. Adaptive functioning as measured by the Vineland Adaptive Behavior

Scale

3. ADHD symptomatology as measured by the ADHD Rating Scale

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Methods

Participants:

This study used archival data conducted in compliance with standards

established by the institution’s IRB including procedures for informed consent.

Participants were evaluated for clinical or research purposes in the autism center

of a children’s hospital. All participants with ASD met DSM-IV or DSM-5

diagnostic criteria as assessed by an experienced clinician. All ASD participants

also received the Autism Diagnostic Interview or Autism Diagnostic Interview-

Revised (Le Couteur et al., 1989; Lord et al., 1994) and/or the first or second

edition of the Autism Diagnostic Observation Schedule (ADOS; Lord et al., 2000;

ADOS-2; Lord et al., 2012). The ADOS and ADI were administered by a trained,

research-reliable clinician. All ASD participants’ scores on the ADI and/or ADOS

met cut-off for the category designated as ‘Broad ASD’ according to criteria

established by the NICHD/NIDCD Collaborative Programs for Excellence in

Autism (see Lainhart et al., 2006). Exclusion criteria for the ASD group included

an IQ < 70 or any known co-morbid medical conditions, such as fragile X

syndrome or other genetic disorders, and brain trauma/injury. See Table 1 for

information on subject demographic characteristics and functioning level.

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Table 1. Subject demographic and clinical characteristics. Measure M SD n Age 10.40 2.72 98 Full Scale IQ+ 104.84 18.78 95 BRIEF Global Executive Composite* 65.86 10.30 98 BRIEF Behavior Regulation Index* 65.00 12.07 98 BRIEF Metacognition Index* 64.66 9.69 98 Vineland - Communication+ 83.90 12.75 88 Vineland - Daily Living Skills+ 87.41 15.60 88 Vineland - Socialization+ 79.62 13.21 86 Note: Full Scale IQ and Vineland scores are reported as standard scores (M=100, SD=15); BRIEF scores are reported as T scores (M=50, SD=10)

Measures:

Children’s Communication Checklist – 2 (CCC-2; Bishop, 2003)

The Children’s Communication Checklist (CCC-2) is a measure designed

to assess children’s communication skills in the areas of pragmatics, syntax,

morphology, semantics, and speech in children aged 4 to 16 years, 11 months

who use full sentences and whose primary language is English. The current

study utilized the parent report version of this questionnaire to rate the

frequency that the child demonstrates the communication behavior described in

each item. The CCC-2 contains 70 items scored on a Likert-type scale, with the

first 50 (e.g., Does not recognize when other people are upset or angry) scored

from 0 (less than once a week or never) to 3 (several times (more than twice) a

day (or always)), and the remaining 20 (e.g., Makes good use of gestures to get

his or her meaning across) with the same ranges of scores, but reverse scored.

The purpose of the CCC-2 is to identify children with pragmatic language

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impairment, children who may have a speech and language impairment that

require a further comprehensive speech and language assessment, and children

who may require further assessment for ASD. Raw scores are converted to a

scaled score which are used to determine the General Communication

Composite (GCC) Standard Score. The GCC is expressed as a standard score that

has a mean of 100 and a standard deviation of 15. The current study utilized the

Structural and Pragmatic Language subtest scores as variables of interest.

Behavior Rating Inventory of Executive Functioning (BRIEF; Gioia et al., 2000)

The Behavior Rating Inventory of Executive Functioning (BRIEF; Gioia et

al., 2000) is an 86-item informant (for the current study, parent) report that

measures EF-related behaviors in children aged 5-18 years. Ratings of the items

follow a Likert-type scale from 1 (Never) to 3 (Often). The BRIEF provides an

overall Global Executive Composite score, which can be broken down into two

higher-order indices: the Behavioral Regulation Index and the Metacognition

Index. The Behavior Regulation Index is in turn composed of the Inhibition,

Shift, and Emotional Control scales while the Metacognition Index includes the

Initiate, Working Memory, Planning and Organization, Organization of

Materials, and Monitor scales. Higher T-scores (Mean=50, Standard

Deviation=10) are indicative of more difficulties such that T-scores > 65 are

suggestive of clinical impairment (Gioia et al., 2000). The scores for the BRIEF

indices were utilized as variables of interest in the current study.

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Vineland Adaptive Behavior Scales, Second Edition (VABS-II; Sparrow,

Cicchetti, & Balla, 2005)

The Vineland Adaptive Behavior Scales-II is a semi-structured interview

that is administered to parents as a measure of how many age appropriate,

adaptive behavioral skills a child or adult exhibits in their natural environment

(Sparrow et al., 2005). For school-age children and adults the VABS-II has three

main domains: Communication, Daily Living Skills, and Socialization. Higher

scores indicate better functioning. From the VABS-II dependent variables of

interest include the Socialization, Communication, and Daily Living Skills These

scores are expressed as standard scores (Mean = 100, Standard Deviation = 15).

ADHD Rating Scale – (DuPaul, Power, Anastopoulos, & Reid, 1998)

The ADHD Rating Scale (DuPaul, Power, Anastopoulos, & Reid, 1998)

assesses severity in inattention and hyperactivity/impulsivity symptoms. This

18-question scale yields two domains: inattention and hyperactivity/impulsivity.

For each question, parents use a 0-3 scale to rate the participant. A higher score

indicates greater symptom severity, and a score of 2 or 3 is considered a

significant symptom; six or more significant symptoms in either the inattention

or hyperactivity/impulsivity domains meet criteria for an ADHD diagnosis.

Scores from the inattention and hyperactivity domains served as variables of

interest in the current study.

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Data Analysis:

The profile of structural and pragmatic language function on the CCC-2

was examined using repeated measures ANOVA in this sample of children with

ASD. In order to examine associations between pragmatic language and

executive functioning, adaptive skills, and ADHD symptomatology, hierarchical

multiple regressions were completed with CCC-2 Pragmatic Language scores

serving as the independent variable and BRIEF Index scores, Vineland domain

scores, and ADHD Rating Scale scores serving as the dependent variables. CCC-2

Structural Language scores and demographic predictors (i.e., age and Full-Scale

IQ) were entered in the first block (serving as control/nuisance variables),

followed by the CCC-2 Pragmatic Language scores in the second block.

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Results

A repeated measures ANOVA revealed a main effect of scale (F=31.55, p<.001)

indicating that there was not a flat profile of scores across CCC-2 scales. Children

with ASD in this sample showed the lowest scores in the domain of nonverbal

communication and highest scores in the domains of speech, syntax, and

semantics (see Table 2). Scaled scores of 4 or lower on the CCC-2 indicate

significant clinical impairment (i.e., 2+ standard deviations below the population

mean of 10). Over half of the children with ASD in this sample scored two or

more standard deviations below the population mean on the nonverbal

communication scale (see Table 2).

Table 2. Parent ratings on the Children’s Communication Checklist-Second Edition among 98 children with autism spectrum disorder. Measure M SD % scoring 1+ SD

below the mean % scoring 2+ SD below the mean

Speech 8.14 3.01 34.7 % 13.3 % Syntax 8.69 3.14 27.6 % 12.2 % Semantics 8.10 2.49 37.8 % 6.1 % Coherence 6.70 2.96 55.1 % 28.6 % Initiation 6.51 2.56 62.2 % 28.6 % Scripted Language 7.09 2.43 50.0 % 20.4 % Context 6.46 2.85 59.2 % 33.7 % Nonverbal 4.83 2.66 81.6 % 53.1 % Social Relationship 5.71 2.70 71.4 % 39.8 % Interests 6.26 2.79 66.3 % 31.6 % Note: CCC-2 scores are reported as scaled scores (M=10, SD=3)

None of age, IQ, or structural language was a significant predictor of

Behavior Regulation Index scores; however, pragmatic language was (see Table

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3). Age also was not a significant predictor of Metacognition Index scores, but IQ

was. Nevertheless, pragmatic language predicted additional variance in

Metacognition Index scores above and beyond IQ (see Table 3).

Table 3. Language scores regressed onto age, IQ, and real world executive function ratings. Predictor B SE B t B SE B t Behavior Regulation

Index Metacognition Index

Step 1 • • • • • • Age -0.74 0.46 -1.61 -0.09 0.34 -0.26 Full Scale IQ -0.10 0.07 -1.44 -0.20 0.05 -

4.08** Step 2 • • • • • • Age -.62 0.42 -1.47 -0.04 0.34 -0.12 Full Scale IQ -0.01 0.07 -0.09 -0.17 0.06 -

3.10** Structural Language 0.41 0.66 0.62 0.42 0.53 0.80 Pragmatic Language -2.79 0.68 -4.11** -1.38 0.54 -2.55* *p < .05, **p < .01.

Age and IQ were significant predictors of adaptive communication skills;

however, structural and pragmatic language scores were not. In contrast,

pragmatic language was a significant predictor of not only Daily Living Skills,

but also Socialization skills, while none of age, IQ, and structural language was

predictive of these two adaptive functioning domains (see Table 4).

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Table 4. Language scores regressed onto age, IQ and adaptive functioning scores. Predictor B SE t B SE t B SE t

Communication Daily Living Skills Socialization Step 1 • • • • • • • Age -1.11 0.48 -2.33* -1.02 0.34 -1.62 -0.46 0.52 -0.88 Full Scale IQ 0.26 0.06 4.13** 0.15 0.05 1.73 0.13 0.07 1.88 Step 2 • • • • • • • Age -1.18 0.47 -2.53* -1.01 0.62 -1.64 -0.50 0.45 -1.12 Full Scale IQ 0.18 0.07 2.59* 0.10 0.09 1.04 -0.00 0.07 -0.02 Structural Language

0.99 0.68 1.45 -0.52 0.90 -0.58 0.42 0.66 0.65

Pragmatic Language

0.76 0.71 1.06 2.16 0.95 2.28* 2.94 0.69 4.24**

Regression analysis revealed IQ, but none of age, structural and pragmatic

language, to be a significant predictor of inattention symptomatology (see Table

5). However, pragmatic language was a significant predictor of hyperactivity

symptomatology while age, IQ, and structural language were not (see Table 5).

Table 5. Language scores regressed onto age, IQ, and ADHD symptomatology ratings. Predictor B SE B t B SE B t Inattention Hyperactivity Step 1 • • • • • • Age 0.15 0.15 1.00 -0.21 0.15 -1.39 Full Scale IQ -0.06 0.02 -3.62** -0.03 0.02 -1.93 Step 2 • • • • • • Age 0.14 0.15 0.93 -0.24 0.15 -1.63 Full Scale IQ -0.06 0.02 -3.41** -0.03 0.02 -1.76 Structural Language 0.19 0.17 1.11 0.23 0.16 1.40 Pragmatic Language -0.28 0.18 -1.58 -0.47 0.17 -2.78* Note: Inattention = CASI ADHD inattention symptom count; Hyperactivity = CASI ADHD hyperactivity symptom count *p < .05, **p < .01.

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Discussion

The current study examined (1) the profile of structural and pragmatic

language skills within a relatively large group of children with ASD without

intellectual disability and (2) the associations of structural and pragmatic

language with EF, adaptive functioning and ADHD symptomatology. The

profile of language functioning in children with ASD was characterized by

weaknesses in pragmatic language relative to structural language. Furthermore,

pragmatic language, unlike structural language, was associated with components

of EF, adaptive functioning and ADHD symptomatology.

In general, previous studies have found that individuals with ASD are

more impaired on the CCC-2 than other clinical populations, such as specific

language impairment, pragmatic language impairment, ADHD, or Williams

syndrome (Botting, 2004; Helland et al., 2012; Philofsky et al., 2007). Although

there is no control group in the current study, utilizing the standardization

sample (i.e., norm-referenced scores) as an index of atypicality, we find a relative

strength in structural language scales (e.g., speech, syntax, and semantics) and a

relative weakness in pragmatic language scales (e.g., nonverbal communication)

among children with ASD. This pattern of findings in ASD corroborates a

growing literature (Bishop & Baird, 2001; Geurts et al., 2004; Norbury et al., 2004;

Volden & Phillips, 2010). For example, studies by both Reisinger, Cornish and

Fombonne (2011) and Geurts and Embrecht (2008) found that individuals with

ASD have more pragmatic than structural language difficulties compared to

21

typically developing/clinical control groups with nonverbal communication also

being one of the most impaired subtest scores. Two studies looked at populations

that had been excluded from this study (e.g., intellectual disability, neurogenetic

disorders such as fragile X syndrome). Results found that individuals with sex

chromosome trisomies (e.g., XXY/Klinefelter’s syndrome) showed impairments

across all scales with particular weakness on the pragmatic language scale of

context (Bishop et al., 2015). The profile of individuals with intellectual disability

showed impairments in pragmatic language, however, individuals with ASD

showed more severe pragmatic impairments (Botting, 2004).

EF is a well-established area of impairment among children with ASD

(Chan et al., 2009; Kenworthy et al., 2008; Granader et al., 2014) and, in fact,

several treatments have been developed to target these deficits in ASD (e.g.,

Unstuck and On Target!; Kenworthy et al., 2014). As predicted, we found that

pragmatic language predicted both components of EF measured in this study,

behavioral regulation and metacognition from the BRIEF over and above the

influences of age (no correlation with EF) and IQ (associated with

metacognition). At least one previous study has found correlations between EF

using performance-based tasks (e.g., generativity/verbal fluency as measured by

the Use of Objects task and Pattern Meanings task; response inhibition as

measured by the Walk Don’t Walk task from the Test of Everyday Attention for

Children) and pragmatic language as measured by the CCC (Bishop & Norbury,

2005). However, to our knowledge, the current study is the first to link pragmatic

22

language functioning and real-world EF (using the BRIEF) in a group of

individuals with ASD. These findings also corroborate prior work in ADHD. In

particular, it might be, as suggested by Geurts et al. (2004), that EF accounts for

the pragmatic language difficulties found in individuals with ADHD while both

EF and theory of mind deficits underlie pragmatic language difficulties in

individuals with ASD. In that sense, EF difficulties might be a shared route to

pragmatic language difficulties in ADHD and ASD, though the particular

components of EF contributing to pragmatic failures could differ for each of

these groups, given their unique EF profiles (e.g., Gioia et al., 2002).

Adaptive functioning is one of the primary indices of outcome in ASD

groups, and as such, serves as a valuable correlate of pragmatic language skills.

Pragmatic language as measured by the CCC-2 was predictive of performance on

the daily living skills and socialization subscales of the Vineland Adaptive

Behavior Scales–II (VABS-II). Utilizing a performance-based measure of

pragmatic language, Reichow et al. (2008) also found that pragmatic language, as

measured by the CASL, was positively associated with the adaptive social

functioning, as measured by the VABS-II, in ASD. Our results, on the other hand,

are inconsistent with findings from Volden et al. (2009) who, using another

performance-based measure, the TOPL, did not find pragmatic language to be

associated with any subscale scores from the VABS. However, a later study

conducted by Volden and Phillips (2010) concluded that the CCC-2 had better

sensitivity to identify pragmatic issues in ASD; therefore, inconsistent results

23

could relate to both a different measure being used in the study and the reduced

sensitivity of the TOPL. Taken together, there appears to be a positive association

between pragmatic language and adaptive (particularly social) functioning in

ASD.

ADHD and ASD are commonly comorbid with one another (Leyfer et al.,

2006), and both disorders are known to have pragmatic language impairments,

though they are more severe in ASD (Geurts et al., 2004; Green et al., 2014). The

presence of ADHD symptoms in the context of ASD has been shown to

exacerbate ASD-related deficits in other domains (Geurts et al., 2004; Yerys et al.,

2009). Yerys et al. (2009), for example, found that ADHD symptoms exacerbated

adaptive functioning and metacognition (working memory) impairments in

ASD. Accordingly, we found that pragmatic language skills were associated with

hyperactivity (not inattention) symptoms, in particular, in ASD. Previous

research in the context of ADHD alone has shown a significant relationship

between pragmatic language functioning and both hyperactivity and inattention

symptoms (Green, Johnson, & Bretherton, 2014). Overall, the current study’s

findings are consistent with our hypothesis that ADHD+ASD may represent a

‘double hit’ or additive model, whereby comorbid ADHD symptoms in ASD

serve, if anything, to worsen pragmatic language deficits. Although this

association had, until now, not been explored previously in ASD, at least one

other study also pinpointed impulsivity/hyperactivity as a key predictor of

24

pragmatic language problems in young children with ADHD (Geurts &

Embrechts, 2008).

Limitations:

There are several limitations to consider in the current study. For example,

there was no typically developing or clinical control group, however, the present

study relied upon a representative and recently acquired standardized sample to

assess impairments and relative strengths and weaknesses in ASD. In addition,

due to IQ<70 being an exclusion criterion, the results from this study cannot be

applied to individuals with both ASD and ID. Furthermore, this study relied on

results from parent report as opposed to direct observation. It should be noted,

however, that parents as the primary caregivers of their children, are the most

knowledgeable informants of their children’s behavior and therefore will have

had the largest window in which to observe these behaviors to provide reliable

reports.

25

Conclusions/Future Research

Future research should explore the possibility of cascading positive

influences from interventions that target EF (e.g., Unstuck and On Target!;

Kenworthy et al., 2014) in ASD. Given that the current study suggests

associations between pragmatic language and EF, improving EF might result in a

‘knock-on’ effect that serves to improve some pragmatic language skills as well.

This is also true for adaptive functioning in that treating pragmatic language

deficits or targeting them in therapy could have positive outcomes in adaptive

functioning skills in ASD. However, because this study involved cross-sectional

analyses, it is impossible to determine causality and primacy in terms of which

behavior has the initial impact to influence the others. Longitudinal/Treatment

studies would be better suited to assess causal relationships between pragmatics

and these other related behavioral constructs (e.g., EF and adaptive functioning).

26

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