Phonological Representations in Children with Autism Spectrum DisorderRon Pomper,1 Susan Ellis Weismer,1 Jenny Saffran,1 Tristan Mahr,1 and Jan Edwards2

1 University of Wisconsin-Madison, 2 University of Maryland

• Early interventions improve language outcomes for

some children with autism spectrum disorder (ASD),1

however, 30% of children with ASD remain minimally

verbal.2 Identifying relative strengths and weaknesses in

language acquisition for children with ASD may help

tailor and improve interventions.

• Children with ASD have superior performance in non-

speech auditory tasks,3 but worse performance in

language comprehension tasks.4 Less is known about

speech perception abilities for children with ASD.5

• Do toddlers with ASD have more or less detailed phonological representations of familiar words compared to typically-developing (TD) toddlers?

Results

1 Rogers, S.J., & Vismara, L.A. (2008). J Clin Child Adolesc Psychol, 37(1), 8-38

2 Tager-Flusberg, H., & Kasari, C. (2013). Autism Research, 6(6), 479-493

3 Happe, F., & Frith, U. (2006). J Autism Dev Disord, 36(1), 5-25

4 Ellis Weismer, S., Haebig, E., Edwards, J., Saffran, J., & Venker, C.E. (2016). J Autism Dev Disord, 46(12), 3755-3769

5 Kuhl, P.K., Coffey-Corina, S., Padden, D., & Dawson, G. (2005). Dev Sci, 8(1),

F1-F12

6 Swingley, D., & Aslin, R.N. (2002). Psych Sci, 13(5), 480-484.

AcknowledgmentsThe authors have no financial or non-financial conflicts of interest. This research

was funded by the National Institutes of Health: NIDCD R01 DC012513, NICHD R37

HD037468, NICHD F31 HD091969, and NICHD P30 HD003352 core grant to the

Wiasman Center. This work was part of the Little Listeners Project:www.littlelisteners.waisman.wisc.org. Contact: ron.pomper@wisc.edu

Discussion• When collapsing across all trials, ASD and TD toddlers

were equally affected by mispronunciations, suggesting

they have the same level of detail in their phonological

representations of familiar words.

• When separating trials based on whether toddlers were

fixating the target or the distractor object at target word

onset, we find evidence that toddlers with ASD and TD

may be affected differently by mispronunciations.

• Group differences in overall word recognition accuracy

were related to verbal skills, but not nonverbal skills.

This dissociation rules out an important alternative

explanation: that toddlers who perform better on one

lab task perform better on other lab tasks (regardless of

the content).

Presented at the 2018 SRCLD Meeting

Participants

• 64 toddlers with ASD (17 female), mean age of 30.6

months (range: 24-36)

• 31 typically-developing (TD) toddlers (13 female),

mean age of 20.5 months (range: 18-24)

• Toddlers with ASD were diagnosed by an experienced

psychologist who administered ADOS-2 and ADI-R

Phonological Representations

• Assessed using a looking-

while-listening task5

• Saw pictures of two

familiar objects

• Heard a sentence

labelling one object with

either a Correct Pronunciation (CP) or

Mispronunciation (MP)

• Eye movements video recorded and coded offline

Offline Measures

• Verbal skills using Preschool Language Scales, 4th

Edition (Auditory Comprehension score) and

MacArthur-Bates Communicative Development

Inventories Words and Sentences (# of words says)

• Nonverbal skills using Mullen Scales of Early Learning

(Visual Reception scale)

References

The time courses of toddlers’ fixations to the target object were analyzed using Growth Curve Analysis (GCA).

Tests of significance were performed using model comparisons (-2*log-likelihood). The sections below analyze

the time course of fixations for all trials, then trials separated based on whether toddlers were fixating the

target object (e.g., cow) or the distractor object (e.g., shoe) at the onset of the target word (e.g., “cow”).

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lmer(elog ~ (ot1+ot2+ot3)*Condition*Group + ((ot1+ot2+ot3)*Condition|Sub.Num), data=d.gca, weights=1/wts, control=lmerControl(optimizer='bobyqa'),REML=FALSE)

Toddlers were less accurate in fixating the target object when it was labelled with a MP (e.g., “gow”) compared to a CP (e.g., “cow”).• Significant effect of Condition on t0, t2, and t3,

!2(1)’s > 5.6, p’s < .02

Toddlers in the ASD Group were less accurate in fixating the target compared to the TD Group.• Significant effect of Group on t0, t1, and t2,

!2(1)’s > 10.4, p’s < .002

The effect of Mispronunciations on accuracy was the same for toddlers in both Groups.• Non-significant effect of Condition:Group on t0, t1, t2, and t3,

!2(1)’s < 2, p’s > .16

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For target-initial trials, there was a strongereffect of Mispronunciations for toddlers in the TD Group compared to ASD Group• Significant effect of Condition:Group on t0 and t2,

!2(1)’s > 8.6, p’s < .01

No effect of Mispronunciations for toddlers in the ASD Group• Non-significant effect of Condition on t0 and t2,

!2(1)’s < 2.3, p’s > .13

…but a significant effect for toddlers in the TD Group• Significant effect of Condition on t0 and t2,

!2(1)’s > 19.9, p’s < .001

For distractor-initial trials, the effect of Mispronunciations was the same for toddlers in both Groups• Non-significant effect of Condition:Group on t0, t1, t2, and t3,

!2(1)’s < 1.4, p’s > .24

Significant effect of Mispronunciations for toddlers in the ASD Group• Significant effect of Condition on t0 and t2,

!2(1)’s > 7.4, p’s < .01

…and in the TD Group• Significant effect of Condition on t0,

!2(1) = 7.4, p < .01

After controlling for differences in verbal skills:• toddlers in the ASD Group were equally accurate in

fixating the target object compared to the TD Group• Non-significant effect of Group on t0, t1, t2, and t3,!2(1)’s < 1.1, p’s > .29

• the effect of Mispronunciations was the same for

toddlers in both Groups• Non-significant effect of Condition:Group on t0, t1, t2, and t3,!2(1)’s < 1.8,

p’s > .18

After controlling for differences in nonverbal skills:• toddlers in the ASD Group were less accurate in fixating

the target object compared to the TD Group• Significant effect of Group on t0, t1, and t2,!2(1)’s > 4.8, p’s < .05

• the effect of Mispronunciations was the same for

toddlers in both Groups• Non-significant effect of Group on t0, t1, t2, and t3,!2(1)’s < 1.3, p’s > .25

Offline MeasuresIntroduction

Method