Brief Report: Prompted Pretend Play in Autism1

Similar documents
The relationship between symbolic play and executive function in young children

Symbolic Play in Autism: A Review

Melissa Heydon M.Cl.Sc. (Speech-Language Pathology) Candidate University of Western Ontario: School of Communication Sciences and Disorders

Autism. Laura Schreibman HDP1 11/29/07 MAIN DIAGNOSTIC FEATURES OF AUTISTIC DISORDER. Deficits in social attachment and behavior

Generating Novel Ideas: Fluency Performance in High-functioning and Learning Disabled Individuals with Autism

University of Bristol - Explore Bristol Research

To Match or Not To Match? Methodological Issues in Autism-Related Research

Is theory of mind understanding impaired in males with fragile X Syndrome? Grant, C., Apperly, I. & Oliver, C

40

Object Lessons. The Questions

5 Verbal Fluency in Adults with HFA and Asperger Syndrome

Brief Report: An Independent Replication and Extension of Psychometric Evidence Supporting the Theory of Mind Inventory

Fact Sheet 8. DSM-5 and Autism Spectrum Disorder

Language Outcomes for Preverbal Toddlers with Autism

Joanna Bailes M.Cl.Sc (SLP) Candidate University of Western Ontario: School of Communication Sciences and Disorders

Imagining Real and Unreal Things: Evidence of a Dissociation in Autism

! Introduction:! ! Prosodic abilities!! Prosody and Autism! !! Developmental profile of prosodic abilities for Portuguese speakers!

Brief Report: Interrater Reliability of Clinical Diagnosis and DSM-IV Criteria for Autistic Disorder: Results of the DSM-IV Autism Field Trial

INFORMATION PAPER: INTRODUCING THE NEW DSM-5 DIAGNOSTIC CRITERIA FOR AUTISM SPECTRUM DISORDER

Table 1: Comparison of DSM-5 and DSM-IV-TR Diagnostic Criteria. Autism Spectrum Disorder (ASD) Pervasive Developmental Disorders Key Differences

Is Theory of Mind Understanding Impaired in Males with Fragile X Syndrome?

What is Autism? -Those with the most severe disability need a lot of help with their daily lives whereas those that are least affected may not.

Cognitive underpinnings of symbolic pretend play and impossible entity drawings:

Typical Gesture Development

Brooke DePoorter M.Cl.Sc. (SLP) Candidate University of Western Ontario: School of Communication Sciences and Disorders

5. Diagnostic Criteria

An exploration of autistic children s ability to recognise emotions in single word and sentence language conditions

From Diagnostic and Statistical Manual of Mental Disorders: DSM IV

Interrelations Among Social-Cognitive Skills in Young Children with Autism

HANDEDNESS IN CHILDHOOD AUTISM SHOWS A DISSOCIATION OF SKILL AND PREFERENCE

CARBONE CLINIC VIVIAN ATTANASIO VERBAL BEHAVIOR INSTITUTE AND TAMARA KASPER CENTER FOR AUTISM TREATMENT

Autism and symbolic play

Cover Page. The handle holds various files of this Leiden University dissertation.

The Context and Purpose of Executive Function Assessments: Beyond the Tripartite Model

BAR ILAN UNIVERSITY. Peer Collaboration Intervention for Minimally. Verbal Children with Autism Spectrum

Enhanced Visual Search for a Conjunctive Target in Autism: A Research Note

PRETEND PLAY AND CHILDREN WITH AUTISM SPECTRUM DISORDER: DEFICITS AND INTERVENTIONS. By Emily J. Jorgenson. Honors Thesis

Domain specificity in conceptual development: Neuropsychological evidence from autism*

Behavior, Language, and Development in Three-Year-Old Children'

Stability of the ADI-R

Fostering Communication Skills in Preschool Children with Pivotal Response Training

OVERVIEW OF PRESENTATION

Hill, Elisabeth L Executive dysfunction in autism. Trends in Cognitive Sciences, 8(1), pp ISSN [Article]

AUTISM SPECTRUM DISORDER: DSM-5 DIAGNOSTIC CRITERIA. Lisa Joseph, Ph.D.

Autism Spectrum Disorder Pre Cengage Learning. All rights reserved.

Diagnosis Advancements. Licensee OAPL (UK) Creative Commons Attribution License (CC-BY) Research study

Joint Attention. Joint Attention. Joint Attention. Joint Attention and ASD: Enhancing Language and Social Competence

Communication and ASD: Key Concepts for Educational Teams

Floortime - Affectively rich play to match child s individual differences and stimulate developmental growth

Language Comprehension Predicts Later Cognitive Ability and Symptom Severity in Toddlers with ASD

First Concerns. Wh at if I (o r t h e pa r e n t s) h av e c o n c e r n s a b o u t a pat i e n t? 10 Toolkit for Medical Professionals

Autism Spectrum Disorders: An update on research and clinical practices for SLPs

Children's Divergent Thinking Improves When They Understand False Beliefs

USING VIDEO MODELING AND REINFORCEMENT TO TEACH PERSPECTIVE-TAKING SKILLS TO CHILDREN WITH AUTISM LINDA A. LEBLANC AND ANDREA M.

Processing demands in belief-desire reasoning: inhibition or general difficulty?

Language Facility and Theory of Mind Development in Deaf Children

Section 5: Communication. Part 1: Early Warning Signs. Theresa Golem. December 5, 2012

THE INFLUENCE OF ADULT SPEECH ON THE LANGUAGE OF CHILDREN WITH ASD: AN EXAMINATION OF MULTIPLE DIMENSIONS OF RESPONSIVENESS IN TWO CONTEXTS

Categorization in ASD: The Role of Typicality and Development

New Mexico TEAM Professional Development Module: Autism

Financial: Texas Tech University Health Sciences Center will reimburse travel.

The Autism-Spectrum Quotient (AQ) in Japan: A Cross-Cultural Comparison

The Effects of Improved Auditory Feedback on the Verbalizations of an Autistic Child

Julie Bolton M.Cl.Sc (SLP) Candidate University of Western Ontario: School of Communication Sciences and Disorders

ASHA Comments* (ASHA Recommendations Compared to DSM-5 Criteria) Austism Spectrum Disorder (ASD)

Representational Difficulties in Individuals with Autism Spectrum Disorders

6/5/2018 SYLVIA J. ACOSTA, PHD

Convergence Principles: Information in the Answer

The Nuts and Bolts of Diagnosing Autism Spectrum Disorders In Young Children. Overview

Human sex differences in social and non-social looking preferences, at 12 months of age

FAR FROM ACTION-BLIND: REPRESENTATION OF OTHERS ACTIONS IN INDIVIDUALS WITH AUTISM

KNOWING ME, KNOWING YOU: DEICTIC COMPLEXITY IN FALSE- BELIEF UNDERSTANDING LOUISE MCHUGH. YVONNE BARNES-HOLMES and DERMOT BARNES-HOLMES ROBERT WHELAN

Misunderstood Girls: A look at gender differences in Autism

Towards a convergent account of pragmatic language deficits in children with

Pragmatic language impairments

Repetitive Behaviour and Play in Typically Developing Children and Children with Autism Spectrum Disorders

WISC-IV Profiles in Children with Autism Spectrum Disorder. Karen Stack, Dr. Raegan Murphy, Paula Prendeville and Dr.

9.85 Cognition in Infancy and Early Childhood. Lecture 14: Autism

Replacing Challenging Behaviors and Improving Quality of Life through FUNCTIONAL COMMUNICATION TRAINING. Melissa L. Rinaldi, Ph.D.

Enhanced discrimination in autism

Abstract. Background: Figurative language, such as metaphor and metonymy, is very common

Deconstructing the DSM-5 By Jason H. King

In Young Children with ASD Kristy Benefield Speech-Language Pathologist St. Tammany Parish School System

Autism Diagnostic Observation Schedule Second Edition (ADOS-2)

Early Interventions for ASD: State of the Science

Durham Research Online

DSM-IV Criteria. (1) qualitative impairment in social interaction, as manifested by at least two of the following:

Language Outcome in Autism: Randomized Comparison of Joint Attention and Play Interventions

Asperger's Syndrome WHAT IS ASPERGER'S? Article QUICK LINKS :

Matching Strategies in Cognitive Research with Individuals with High-Functioning Autism: Current Practices, Instrument Biases, and Recommendations

Critical Review: Using Video Modelling to Teach Verbal Social Communication Skills to Children with Autism Spectrum Disorder

DSM 5 Criteria to Diagnose Autism

Satiation in name and face recognition

Recognition of Faces of Different Species: A Developmental Study Between 5 and 8 Years of Age

UNIVERSITY OF AKUREYRI

City, University of London Institutional Repository

Autism.

Cognitive Neuroscience of Autism

Using Pivotal Response Training with Peers in Special Education to Facilitate Play in Two Children with Autism

Paraprofessional Training Module

Transcription:

Journal of Autism and Developmental Disorders, Vol. 27, No., 997 Brief Reports Brief Report: Prompted Pretend Play in Autism Tony Charman2 University College London Simon Baron-Cohen University of Cambridge A wealth of studies have confirmed Kanner's (94) view that children with autism have impoverished pretend play (for reviews see Harris, 99; Jarrold, Boucher, & Smith, 99; Wulff, 985). However, there is disagreement about the exact nature of the impairments, the conditions under which the impairments are manifested, and the processes underlying them (Harris, 99; Jarrold et al., 99; Leslie, 987; Perner, 99). One source of the controversy lies in the fact that the production of pretense in children with autism has been assessed under two general setting conditions: (a) unstructured, spontaneous conditions, and (b) structured, prompted, or elicited conditions. All studies show an impairment in the production of pretend play in children with autism (in comparison to mental-aged matched controls) in unstructured, spontaneous conditions (Baron-Cohen, 987; Lewis & Boucher, 988; Riguet, Taylor, Benaroya, & Klein, 98; Sigman & Ungerer, 984; Ungerer & Sigman, 98). After general or specific prompts are given, children with autism tend to produce some pretend play, although in many studies the group differences remain (Riguet et al., 98; Sigman & Ungerer, 984). In two studies they disappeared: Children with autism were unimpaired in pretend play (object substitution) under prompted conditions (Jarrold, Boucher, & Smith, 996; Lewis & Boucher, 988). Jarrold et al. (996) also investigated the ability of children with We are indebted to the staff and pupils at the following schools: Rosemary School, Islington, the Sybil Elgar School, Ealing, and Radlett School for Autism, Herts. The first author was in receipt of a grant from the Central Research Fund, University of London. We are grateful to Cathy Lord and three anonymous reviewers for helpful comments on an earlier draft of this paper. 2Address all correspondence to Tony Charman, Sub-Department of Clinical Health Psychology, University College London, Gower Street, London WCE 6BT, United Kingdom. 25 062-257/97/0600-025$2.50/0 997 Plenum Publishing Corporation

26 Charman and Baron-Cohen autism to generate play acts when prompted ("What else can you pretend to do?"). They found that although children with autism were able to generate pretend play acts, they did so at a significantly slower rate than controls. The findings of intact pretend play under prompted conditions are important for an understanding of the core deficit that underlies the general (unprompted) pretend play deficits in autism. They have been used to challenge Leslie's (987) notion that pretend play involves metarepresentation, the cognitive basis of the young child's developing theory of mind both of which are impaired in autism (see Jarrold, Carruthers, Smith, & Boucher, 994). Lewis and Boucher (988) suggested that since prompting increases the amount of both functional and pretend play, this supports either a generativity or a motivational deficit theory, and that the production of pretend acts per se (and presumably the accompanying representational thinking) is not impaired in autism. In a related account, Jarrold et al. (996) argue that children with autism can engage in the mechanics of pretend play, but are impaired at producing pretense due to generativity problems. Harris (99) interpreted the increase in pretend and functional play, when more external structure (or scaffolding) is provided, as evidence of an executive dysfunction. Given the importance these accounts place on Lewis and Boucher's (988) original demonstration of intact pretend play under prompted conditions, and the findings by Jarrold et al. (996), the study reported below sets out to test the production of simple pretend play by children with autism under prompted conditions, employing a highly structured task previously used with normally developing children (Fein, 975). THE EXPERIMENT Subjects We tested 22 subjects with autism (8 male, 4 female), all of whom had been diagnosed according to established criteria (DSM-III-R, American Psychiatric Association, 987; Rutter, 978) and who were attending a special school for children with autism. In addition, 9 subjects with mental handicap (8 Down syndrome, of uncertain etiology) but without autism (7 male, 2 female) were tested to control for verbal mental age (VMA) and chronological age (CA). Details of the subjects are summarized in Table I. Although there were no differences between the groups in terms of CA and VMA, the subjects with autism had a higher nonverbal mental age (NVMA), ANOVA, F(l, 0) =., p <.00. VMA was assessed using the Test of Reception of grammar (TROG; Bishop, 98), or the British Picture Vocabulary Scale (BPVS; Dunn, Dunn, Whetton, & Pintillie, 982)

Prompted Pretend Play in Autism 27 Table I. Means, Standard Deviations, and Ranges of Chronological Age (CA) and Mental Age (MA) in Months Groups Autism M SD Range Mental handicap M SD Range Nonverbal n CA Verbal MAa MAb 22 9 40. 46.2 90. 48.0 4.8 27.7 6-26 20-66 8-44 49.0 7.6 45.5 4. 6.0 2.8 90-25 20-69 27-66 atrog, BPVS (VMA missing for subject with autism, 2 with mental handicap). bravens Matrices, Merrill-Palmer (NVMA missing for 2 subjects in each group). for those subjects who fell below the floor of the TROG (48 months). NVMA was assessed using Raven's Coloured Progressive Matrices (Raven, 956), or the Merrill-Palmer Scale of Mental Abilities for those subjects who fell below the floor of the Raven's (42 months). Procedure Each subject was tested in a quiet room in his or her school. Subjects were given two functional play and two object substitution tasks (derived from Fein, 975): Functional Trial. Subject presented with a doll and a toy spoon. Object Substitution Trial. Subject presented with a doll and a metal rod. Functional Trial 2. Subject presented with a doll and a toy cup. Object Substitution Trial 2. Subject presented with a doll and a wooden brick. The order of Trials and 2 were counterbalanced across subjects. However, to maximize the scaffolding provided on the object substitution trials these always followed on from the corresponding functional trials. In turn, each set of objects were placed onto a table in front of the subject. The following series of prompts (based on the elicited and instructed conditions employed by Lewis and Boucher, 988) was given until a response was made:. An open prompt was given ("What can you do with these?") and the subject was given 20 seconds to respond. 2. A specific prompt was given ("Let's pretend. Give the dolly a drink of juice.") and the subject was given 20 seconds to respond.. The functional or pretend play action was modeled and a specific prompt was given ("Let's pretend. Give the dolly a drink of juice.") and the subject was given 20 seconds to respond.

28 Charman and Baron-Cohen On each trial, the first response made was scored according to the following criteria:. On the functional trials, functional play was scored if the spoon/cup was placed on the doll's mouth in a feeding/drinking motion. 2. On the object substitution trials, situationally appropriate object substitution was scored if the rod/brick was placed onto the doll's mouth in a feeding/drinking motion. Novel or unprompted object substitution was scored if the rod/brick was employed in a play action other than feeding and drinking with the doll (e.g., the subject pushed the rod horizontally to-and-fro on the doll's mouth and said "cleaning teeth"; the subject put the brick against the doll's hand and said "bag"). To minimize reliance on the rater's interpretation of the action, conservative scoring criteria were adopted, requiring the presence of confirmatory vocalization for the scoring of a novel object substitution. In fact, across all trials many subjects spontaneously named their actions or made appropriate drinking or eating sounds. Thirty trials (5 from each of the two groups of subjects) were videotaped, and a second experimenter rated responses across the five categories: open prompt, specific prompt, modeled, no response, and novel object substitution. Interrater agreement was high. Measured in percentage terms the item-by-item agreement was 90%, and as measured by Cohen's kappa (Cohen, 960) the agreement was 0.85. RESULTS The production of functional and pretend play across the two functional and two object substitution trials is shown in Table II. On the functional trials, in both groups the majority of subjects produced functional play in response to the open prompt on both trials. On the object substitution trials fewer subjects produced pretend play acts in response to the open prompts, with both groups requiring more specific prompting and modeling, or produced no response at all. However, the majority of subjects in both groups did produce examples of object substitution. For the subjects with autism, these tended to be a situationally appropriate object substitution and rarely novel object substitutions. Across the two object substitution trials, significantly more subjects with a mental handicap produced at least one example of novel pretend play (5 subjects produced one novel act, and 6 produced two), compared to the subjects with autism (4 subjects produced one novel act) (x2 = 5., p <.0). Since the conservative scoring criteria adopted required the presence of confirmatory vocalization for the registration of a novel pretend action, it might be that these group differences reflect real differences in the number of vocalizations produced, and not

Prompted Pretend Play in Autism 29 Table II. Subjects Producing Functional and Object Substitution Play Acts in the Functional and Object Substitution Trials Functional play acts in functional trials Open prompt Specific prompt Modeled No response Spoon 7 5 - Autism Cup 9 - Mental handicap Spoon 7 - Cup 7 2 - Rod Brick Rod Brick Situationally appropriate object substitution play acts in object substitution trials Open prompt Specific prompt Modeled No response 9 7 2 4 4 4 6 2 Novel object substitution play acts in object substitution trials 7 0 novel pretense. However, there were no differences between the mean number of vocalizations (mostly naming of actions and objects) produced by the subjects with autism (M =.2, SD =.5) and those with mental handicap (M =.6, SD =.), ANOVA F(l, 9) = 0.85, p >.0. Analysis of CA, VMA, and NVMA for subjects in each group who produced the appropriate play act under open, specific, or modeled prompting, or no response, revealed only two differences. In the autism group, subjects who produced a pretend play act in response to open prompting on the Doll-Rod object substitution trial had a lower CA than those subjects who required specific prompting, or who made no response (99 months vs. 78 months and 79 months, respectively; ANOVA F(,8) = 0.6, both post hoc Scheffe p <.0). In the mental handicap group, subjects who produced a pretend play act in response to open prompting on the Doll-Brick object substitution trial had a higher VMA than those subjects who required specific prompting or modeling (5 months vs. 2 months and 25 months, respectively; ANOVA F(, 4) - 4.58, both post hoc Scheffe p <.0). In the autism group, those subjects who produced one example of novel object substitution had a higher NVMA than those who did not (24 months vs. 8 months; ANOVA F(l, 7) = 7.56, p <.02). In the mental handicap group, those subjects who produced at least one example of novel objects substitution had a higher VMA than those who did not, although the difference just failed to reach significance (48 months vs. 40 months; ANOVA F(l, 9) = 5.9, p <.08).

0 Charman and Baron-Cohen DISCUSSION The present study found that when prompted, school-age and adolescent subjects with autism did not differ from controls with mental handicap in their production of functional play acts and situationally appropriate object substitution. Such results are consistent with those obtained by Lewis and Boucher (988) and Jarrold et al. (996). They contrast with those of Sigman and Ungerer (984), who found that children with autism were impaired on both functional and object substitution play even when prompted. This may be because Sigman and Ungerer used younger, less able, subjects with autism. The finding that in the present study subjects with autism produced fewer novel, or unscaffolded, pretend play acts is also consistent with Jarrold et al.'s (996) finding that children with autism generate fewer examples of novel play acts, both with and without props. Does the finding that subjects with autism produced situationally appropriate object substitution challenge Leslie's (987) thesis? To reiterate, Leslie claims that a deficit in metarepresentation underlies the pretend play and theory of mind impairments in autism. The present study only challenges Leslie's thesis if the acts necessarily involve metarepresentation. However, like Lewis and Boucher's (988) study, the present study deliberately employed specific prompting and instruction, in order to maximize the chances of object substitution occurring. Thus, we cannot rule out what Baron-Cohen (990) called "intelligent guessing": With only limited junk objects available, the subjects may relate the objects together in a manner that resembles pretense without the mental attitude pretend being necessarily represented. This is because, for situationally appropriate object substitution, all the cues are provided by the experimenter, while the ability to generate or create the idea for pretense is not tested. Boucher and Lewis (990) replied to this criticism by listing examples of play acts by all 5 subjects with autism that they claim demonstrate truly imaginative play. In fact, in the present study, although most subjects with autism produced situationally appropriate object substitutions, very few subjects with autism were able to demonstrate an ability to actively generate and produce novel, unprompted object substitutions. Another factor that limits interpretation of the present findings is that the object substitution trials followed the related functional trial, so that a perseverative response from one trial to the next could be scored as object substitution. To produce novel object substitution the subjects had to overcome any tendency to perseverate actions in the previous trial. Since children with autism may have problems inhibiting prepotent responses (Hughes & Russell, 99), this may have made the production of novel play acts in this context more difficult for them. Furthermore, the junk

Prompted Pretend Play in Autism objects also shared some perceptual similarity to the functional objects, and object substitution of perceptually similar objects may not require the same sophistication of representational thought as when perceptually dissimilar objects are used in object substitution (Jarrold et al., 996). In addition, the study demonstrates only that subjects with autism with a VMA of 4 years are able to produce very basic-level object substitution pretend play under prompted conditions, at a level seen in normally developing children in the second half of the second year of life (Fein, 98; Leslie, 987). There may therefore be a delay in this domain, particularly with younger children with lower developmental levels. Particular caution is warranted in this respect, since the autism group had a significantly higher NVMA than the controls with mental handicap. Further work is needed to track the development of more complex and social play in autism, under both prompted and spontaneous conditions. In summary, we have replicated Lewis and Boucher's (988) and Jarrold et al's (996) findings that children with autism are able to produce what looks like pretend play under prompted conditions. In addition, in line with Jarrold et al's findings, fewer subjects with autism produced novel, unprompted pretend play acts. As argued earlier, this may pose no challenge to Leslie's (987) metarepresentation thesis, although neither does it provide specific support. Whether it additionally supports Harris's (99) executive dysfunction account or the generativity thesis set out by Lewis and Boucher (988), Baron-Cohen (990), and Jarrold et al. (996) awaits the outcome of further research. REFERENCES American Psychiatric Association. (987). Diagnostic and statistical manual of mental disorders (rd ed., rev.). Washington, DC: Author. Baron-Cohen, S. (987). Autism and symbolic play. British Journal of Developmental Psychology, 5, 9-48. Baron-Cohen, S. (990). Instructed and elicited play in autism: A reply to Lewis and Boucher. British Journal of Developmental Psychology, 8, 207. Bishop, D. (98). The test for reception of grammar. London: Medical Research Council, Applied Psychology Unit, Cambridge. Boucher, J., & Lewis, V (990). Guessing or creating? A reply to Baron-Cohen. British Journal of Developmental Psychology, 8, 205-206. Cohen, J. (960). A coefficient of agreement for nominal scales. Educational and Psychological Measurement, 20, 7-46. Dunn, L. M., Dunn, L. M., Whetton, C, & Pintillie, D. (982). British Picture Vocabulary Scale. London: NFER-Nelson. Fein, G. G. (975). A transformational analysis of play. Developmental Psychology,, 29-296. Fein, G. G. (98). Pretend play in childhood: An integrative review. Child Development, 52, 095-8.

2 Charman and Baron-Cohen Harris, P. L. (99). Pretending and planning. In S. Baron-Cohen, H. Tager-Flusberg, & D. Cohen (Eds.), Understanding other minds: Perspectives from autism. Oxford: Oxford University Press. Hughes, C, & Russell, J. (99). Autistic children's difficulty with mental disengagement from an object: Its implications for theories of autism. Developmental Psychology, 29, 54-549. Jarrold, C. Boucher, J., & Smith, P. (99). Symbolic play in autism: A review. Journal of Autism and Developmental Disorders, 2, 28-07. Jarrold, C, Boucher, J., & Smith, P. (996). Generativity deficits in pretend play in autism. British Journal of Developmental Psychology, 4, 275-00. Jarrold, C, Carruthers, P., Smith, P. K., & Boucher, J. (994). Pretend play: Is it metarepresentational? Mind and Language, 9, 445-468. Kanner, L. (94). Autistic disturbances of affective contact. Nervous Child, 2, 27-250. Leslie, A. M. (987). Pretence and representation: The origins of "theory of mind." Psychological Review, 94, 42-426. Lewis, V, & Boucher, J. (988). Spontaneous, instructed and elicited play in relatively able autistic children. British Journal of Developmental Psychology, 6, 25-9. Perner, J. (99). Rethinking the metarepresentation theory. In S. Baron-Cohen, H. Tager- Flusberg, & D. Cohen (Eds.), Understanding other minds: Perspectives from autism. Oxford: Oxford University Press. Raven, J. (956). The coloured progressive matrices. London: H. K. Lewis. Riguet, C. B., Taylor, N. D., Benaroya, S., & Klein, L. S. (98). Symbolic play in autistic, Down's and normal children of equivalent mental age. Journal of Autism and Developmental Disorders,, 49-448. Rutter, M. (978). Diagnosis and definition of childhood autism. Journal of Autism and Childhood Schizophrenia, 8, 9-6. Sigman, M., & Ungerer, J. A. (984). Cognitive and language skills in autistic, mentally retarded, and normal children. Developmental Psychology, 20, 29-02. Ungerer, J., & Sigman, M. (98). Symbolic play and language comprehension in autistic children. Journal of the American Academy of Child Psychiatry, 20, 8-7. Wulff, S. B. (985). The symbolic and object play of children with autism: A review. Journal of Autism and Developmental Disorders, 5, 9-48.