Journal of Autism and Developmental Disorders, Vol. 29, No. 3, 1999

Autism During Infancy: A Retrospective Video Analysis ofSensory-Motor and Social Behaviors at 9-12 Months of Age

Grace T. Baranek1

This retrospective video study explored the usefulness of sensory-motor measures in additionto social behaviors as early predictors of autism during infancy. Three groups included 11children with autism, 10 with developmental disabilities, and 11 typically developing chil-dren. Home videos were edited to obtain a 10-minute cross-section of situations at 9-12 monthsfor each subject. Using interval scoring, raters coded several behavioral categories (i.e., Look-ing, Affect, Response to Name, Anticipatory Postures, Motor/Object Stereotypies, SocialTouch, Sensory Modulation). Nine items, in combination, were found to discriminate the threegroups with a correct classification rate of 93.75%. These findings indicate that subtle symp-toms of autism are present at 9-12 months, and suggest that early assessment procedures needto consider sensory processing/sensory-motor functions in addition to social responses duringinfancy. Furthermore, prior to a time that they reported autistic symptoms, caregivers usedcompensatory strategies to increase the saliency of stimuli in order to engage their childrenmore successfully; these strategies may provide a window for earlier diagnosis.

INTRODUCTION

An accurate diagnosis of autism appears reliableno earlier than 2 to 3 years of age (e.g., Lord, 1995)despite the overwhelming conviction that it is a neuro-developmental disorder of prenatal origin (Bailey,Phillips, & Rutter, 1996; Gillberg & Coleman, 1992;Rutter & Schopler, 1987; Volkmar, Stier, & Cohen,1985). The early elusiveness of autism leads to specu-lation about whether symptoms actually do exist ininfancy and if so, whether they are too subtle to bedetected reliably. Earlier diagnosis appears limited by(a) our knowledge of the early development in thoseinfants later diagnosed with autism, and (b) our relianceon conventional classification systems (e.g., DSM-IV;American Psychiatric Association [APA], 1994) based

1 Center for Development and Learning and Division of OccupationalTherapy, CB #7255, University of North Carolina at Chapel Hill,Chapel Hill, North Carolina 27599-7255; e-mail: gbaranek@css.unc.edu

on the "triad" of behaviors (i.e., social, language,and behavioral symptoms) manifested in older childrenwith autism. Both the presence of unusual behaviors(e.g., stereotypies) as well as the absence of typicallydeveloping behaviors (e.g., verbal language) are con-sidered for diagnosis. Therefore, professionals are re-luctant to diagnose autism prior to the age that a childwould typically develop representational capacities andprior to expectations for production of consistent so-cial initiatives such as sharing, offering comfort, andinitiating joint attention.

Moreover, the course of autistic symptomatologymay change considerably with age; thus, symptomsduring infancy may not appear at all like later mani-festations of the disorder (Bailey et al, 1996; Gillberget al, 1990; Watson & Marcus, 1988). Research hasalso shown that autistic symptoms are easier to recog-nize as they intensify or become more pervasive withage (Adrien et al., 1993; Lord, 1995; Wing, 1969), andparents' awareness of symptoms also varies with theirchild's stages of development (Stone & Hogan, 1993).

2130162-3257/99/0600-0213S16.00/0 1999 Plenum Publishing Corporation

KEY WORDS: Home movies; autistic symptoms; developmental disabilities; early diagnosis; sensoryprocessing; social responsiveness.

214 Baranek

Early Predictors: Findings and SpeculationsThe essential questions still remain: Can subtle

autistic symptoms be identified during infancy, and if so,what measures would be relevant and sensitive to theseearly behavioral manifestations? Prospective studies ofyoung children (i.e., 18-24 months) have highlighted theimportance of social-communicative functions as earlypredictors of a later, more reliable diagnosis of autism(Baron-Cohen et al., 1996; Lord, 1995). The absence oftypically developing, prelinguistic functions such as pro-todeclarative pointing, showing objects, joint attention,affective exchanges, pretend play, and imitation havebeen specifically cited as markers of autism in youngchildren (e.g., Baron-Cohen et al., 1996; Dawson, Hill,Spencer, Galpert, & Walson, 1990; Lord, 1995; Sigman,Mundy, Sherman, & Ungerer, 1986; Stone, Lemanek,Fishel, Fernandez, & Altmeier, 1990) and these arethought to be precursors of later appearing deficits insocial relatedness and communication. However, thepredictive validity of these behaviors appears question-able prior to about 18 months of age. Perhaps some ofthese indicators may need to be down-graded in order tobe applicable to the infancy period and/or markers inother domains of infant functioning need to be consid-ered. Gillberg et al. (1990) suggested that abnormal per-ceptual responses as well as social deficits may be likelyindicators of autism during infancy.

Although social cognition and communicativefunctions have been investigated widely, there is a dearthof empirical information about the various qualitativeaspects of sensory-motor behaviors (e.g., sensory-perceptual responses, arousal modulation, movementpatterns, object manipulations, postural adjustments)that may be disrupted early in the development of chil-dren with autism. These types of difficulties are reportedextensively in older children with autism (e.g., AdrienOrnitz, Barthelemy, Sauvage, LeLord, 1987; O'Connor& Hermelin, 1967; Ornitz, Guthrie, & Farley, 1977) aswell as in retrospective accounts of the infancy periodbased on medical chart reviews and/or parental reports(Dahlgren & Gillberg, 1989; Gillberg et al., 1990; Kan-ner, 1943; Wing, 1969). An empirical study of sensory-motor functions early in the development of autismcould reveal potential markers of autism that, whilesubtle, may prove foundations to later evolving symp-toms either within or outside of the sensory-motor do-main. Sensory-motor processes are salient from birthand thus may be easily observable throughout infancyprior to the development of abnormalities in many of thehigher level representational capacities (e.g., symbolicthought; theory of mind) that currently have evokedmuch interest in research.

Furthermore, some sensory-motor behaviors mayserve functions underlying several domains of behav-ior early in life. For example, gaze aversion is thoughtto subserve arousal modulation necessary for self-regulatory behaviors and early social interactions (Daw-son & Lewy, 1989; Field, 1981). Both Kanner (1943)and Wing (1969) described a variety of very early de-veloping autistic features that could be conceptualizedas crossing the social/nonsocial distinction (e.g., defi-cient anticipatory postures, intolerance of physical han-dling, hypo- and hyperresponsiveness to sensory stim-uli). Additionally, a variety of specific sensory-seekingbehaviors (e.g., scratching fabrics, staring at lights) arealso reported retrospectively during infancy. Many ofthese qualitatively different sensory-motor behaviorsare not the focus of conventional assessments, and thus,potential markers of autism during infancy could beoverlooked by practitioners.

Retrospective Video Analysis

Due to the impossibility of obtaining autistic in-fants as research subjects, researchers have been seek-ing other methods to identify signs of vulnerability earlyin development. With the advent of affordable videotechnology, families in increasing numbers have homevideos which inadvertently provide documentationof their children's development. Retrospective videoanalysis has shown success as an ecologically validmethodological tool for earlier identification of chil-dren with various psychopathologies (Adrien et al.,1993; Grimes & Walker, 1994; Losche, 1990, Massie,1977; Osterling & Dawson, 1994; Rosenthal, Massie,& Wulff, 1980). Although a myriad of methodologicalproblems are encountered (e.g., difficulty controllingvariables such as the age of subjects and length, con-tent or structure of the video segments), retrospectivevideo analysis currently appears to be an excellent op-tion for accessing very early periods in developmentmonths or years before a child with autism is diagnosed.

Several retrospective video studies conductedspecifically in the autism realm suggest that young chil-dren with autism can be distinguished from typicallydeveloping children with respect to sensorimotor in-telligence (Losche, 1990), orientation to social stimuli(e.g., looking/joint attention) (Osterling & Dawson,1994), and less commonly, motility, sensory modula-tion, and attention (Adrien et al., 1993). Osterling andDawson (1994), in a video study of first birthdays com-paring autistic and typical groups, found that "lookingat other persons" was the best single predictor of a laterdiagnosis of autism. One common problem with these

Autism During Infancy 215

studies is the difficulty in obtaining an appropriate com-parison group (i.e., children with mental retardation).One video study (Adrien et al., 1992) found that a com-bination of 19 social and sensory items differentiatedchildren (6-48 months) with autism from those withmental retardation as well as those with typical devel-opment. However, few of the autistic subjects wereunder 2 years of age, which provided limited informa-tion on the usefulness of some of the items during theinfancy period.

The purposes of this study were to (a) explore theusefulness of sensory-motor variables in addition tosocial markers of autism during the infancy period;(b) identify variables that may indicate differences at9-12 months of ageearlier than previously accom-plished using retrospective video analysis (i.e., earlyprediction); and (c) discriminate between groups ofchildren with autism (AUT), developmental disabili-ties (DD), and typical development (TYP) with respectto these variables (i.e., differential diagnosis).

METHOD

Participant RecruitmentParticipant recruitment was an arduous process,

fraught with unexpected complications, and conse-quently was accomplished through several stages. An es-timated 1,000 families were contacted through personaland professional contacts, advertisements, and directmailings/distributions through hospital-based clinics,public and private schools, early intervention programs,and advocacy groups for children with autism and men-tal retardation. Initial recruitment criteria included thatthe child currently was above 2 years of age, and wasdiagnosed with either autism (for the AUT group) ormental retardation not associated with a physical syn-drome (for the DD group), or was typically developing(for the TYP group). All families were required to havehome videos of their child between birth and 2 years ofage that they were willing to share in this research.

Since there were few responses from families ofchildren diagnosed with mental retardation following2 years of recruitment, the criteria for the DD groupwere modified and expanded. One possible cause forthis difficulty appeared to be that professionals werereluctant to label very young children with mental re-tardation and opted instead for less stigmatizing labelssuch as "developmentally delayed" or "cognitively de-layed." Except in cases of an identifiable syndrome(e.g., Down syndrome), mental retardation was rarelydiagnosed. Thus, the terminology in this study's re-

cruitment literature for the DD group in this study waschanged to reflect "nonspecific or generalized" devel-opmental delays, developmental disabilities, and cog-nitive impairments, and it was expanded to includethose children with mental retardation associated withsyndromes.

The overall positive response rate to the direct mail-ings and distributions was about 10%, with greater suc-cess from those agencies that (a) catered to higher SESareas (e.g., suburbs), (b) collected the responses directly,or (c) provided follow-up after the initial requests weremailed. Generally, connections made through personalcontacts and professional colleagues were often moresuccessful than through those agencies with which lesspersonal contact was possible. A total of 75 familiesagreed to participate, signed the informed consent, al-lowed an interview, and/or provided the research teamwith videos of their child between birth and 2 yearsof age.

In the second stage of screening procedures, thestudy was narrowed further to include only those fam-ilies that had provided good quality videos with suffi-cient content from 9 through 12 months adjusted age.Children were also excluded if they had significantvisual, hearing, or physical impairments (e.g., cerebralpalsy). Thirty-two children remained that met all of theselection criteria and whose families completed allnecessary interview and observational procedures (asdescribed below).

Subject DemographicsThirty-two children, belonging to one of three

groups AUT (n = 11), DD (n = 10), TYP (n =11), werethe subjects in this study. Although their current chro-nological ages varied, all subjects were representedon video at the exact same age group (i.e., 9 through12 months corrected chronological age). There were19 boys (AUT = 10, DD=3, TYP=6) and 13 girls (AUT=1, DD=7, TYP=5). Twenty-seven children (88%) wereCaucasian (AUT=10, DD=8, TYP=9). The remainingfive subjects had the following ethnic breakdown: oneHispanic (AUT= 1); two Asian (DD= 1, TYP=1); oneAfrican American (TYP= 1); and one Native American(DD= 1).

The group of 11 TYP children were all normallydeveloping with no history of developmental or learn-ing problems reported by their parents. They were allfunctioning in the average range on the Vineland Adap-tive Behavior Scales, Interview Edition, Survey Form(VABS; Sparrow, Balla, & Cicchetti, 1984) which waslater administered by the investigator.

216 Baranek

All AUT subjects were originally diagnosed bytheir physician or licensed psychologist using DSM-III-R or DSM-IV (APA, 1994) criteria and, in manycases, the Autism Diagnostic Interview-Revised (ADI-R; Lord, Rutter, & LeCouteur, 1994) as well. Addi-tionally, inclusion criteria for this study were (a) a con-firmation of the diagnosis of Autistic disorder using theDSM-IV and (b) a score above 30 on the ChildhoodAutism Rating Scale (CARS; Schopler, Reichler, &Renner, 1988) administered by the investigator.

The children with DD (n=10) each had a docu-mented developmental disability or mental retardationreported in school or medical records. Specifically, thisgroup included 6 children with Down syndrome, 2 withWilliam syndrome, and 2 with nonspecific mentalretardation/developmental disabilities. They all hadCARS scores below 25 (nonautistic range).

Subject AssessmentsThe CARS was administered to the AUT and DD

groups through an individualized parent interview andsupplementary play observation of each child. Resultsof this assessment and all others are reported as groupdata in Table I.

To compare the AUT and DD groups on criticalvariables, current developmental information was ob-tained. Levels of cognitive functioning (i.e., IntelligenceQuotients/Mental Ages) were obtained from the chil-dren's current medical or school psychological reportsindicating results of standardized assessments that weredetermined to be individually appropriate for each childbased on their age and diagnosis. For this study, theirscores were coded to reflect the overall level of mental

retardation (MR): 0 = Average/Above average intelli-gence (85+); 1 = Borderline (70-84); 2 = Mild MR(55-69); 3 = Moderate MR (40-54); 4 = Severe/Profound MR ( .05.

In addition, all children in this study were assessedfor their current level of developmental maturity/adap-tive behavior using the VABS. The parent most famil-iar with his/her child's daily functioning was used asthe informant, which in all but two cases were the chil-dren's mothers. The interviews were conducted at a lo-cation and time convenient to each family. Parents weresent a summary of the VABS results from this inter-view. Since the children's current chronological agesvaried, developmental ages could not be used as a com-parison. Therefore, the VABS composite standard scorewas used in the study as an index of current develop-mental maturity (DQ) to compare the groups. OverallDQ differences on the VABS Adaptive Composite Stan-dard Score were not statistically significant for the AUTand the DD groups, t (19) = -2.02, p > .05. Also, theVABS Communication Standard Scores were not sig-nificantly different for these two groups, t (19) =-1.06, p > .05. (See Table I.)

Of secondary interest to the study, supplementalmedical and developmental information was obtained onthe subjects and is thus summarized in Table II. The DDgroup was reported to have experienced more frequent(early) medical complications (e.g., jaundice, heart prob-lems, recurrent infections) than either of the other twogroups, x2 (2, N = 32), = 11.04, p < .005. As expected,age at diagnosis was also significantly later for the AUTgroup (M - 33 months), compared with the DD group(M = 3 months) groups, t (19) = 8.25, p < 001. Parentsof both groups overwhelmingly reported onset of de-velopmental problems early (i.e., prior to 18 months);however, the AUT group reportedly evidenced theseproblems significantly later than the DD group, t (19) =5.54, p < .001. In addition, regression (usually noted asa loss of language) was reported by parents in 54% ofthe cases in the AUT group.

Videotape Collection and Review ProceduresInitially, all families were asked to provide any

videotapes of their child that were taken under 2 yearsof age. Copies of the videos were made in a mannerthat was convenient to each family and coded by IDnumber to preserve confidentiality. Families were re-imbursed for the cost of videotapes and postage. Thespecific ages and types of situations on the videos were

Table I. Current Subject Characteristics

Autism DD TypicalCharacteristic M (SD) M (SD) M (SD)

Chronological age (months) 63 (17)Level of MR 2(1)

MildVABS"

Composite SS (DQ) 56 (1 1)Communication SS 63 (23)Daily Living SS 53 (13)cSocial SS 60 (8)cMotor SS 73(14)

652(1)Mild

65(8)71 (8)65 (12)c80(13)c62(9)

53 (25)0

None

106 (7)110 (10)96 (6)

105 (7)108 (11)

CARSb 36 (5)c 20 (2)c a Vineland Adaptive Behavior Scales-Standard Scores.

* Childhood Autism Rating Scale.cp

Autism During Infancy 217

not limited initially, in order to obtain as much footageas possible before deciding how to edit the tapes. Theyincluded segments from family play situations, specialevents, and/or familiar routines (e.g., mealtime). Eachtape was then screened for minimum quality standards.Any tape that was not in standard VHS format or speedwas transferred to be compatible with VHS editingequipment.

Once the tapes were received, they were reviewedin detail and logged according to the child's chrono-logical age during each scenario and specific content.Chronological ages were calculated by full months,based on the child's birth date and corresponding datesappearing on the tapes themselves. [Note: For thosechildren (n = 4) who were born prematurely ( .05, aver-age number of persons evident (n = 4), F(2, 62) =1.14,p > .05, amount of physical restriction, F(2, 62) = 1.32,p > .05, and level of social interaction/structure, F(2,62)= 1.34, p > .05. Those subjects with less than 10 min-utes of usable edited footage were eliminated from thestudya process that resulted in the final selection ofthe 32 children described previously.

The order of the subjects was randomly mixedonto the final master tapes to be used later for codingpurposes. Once the video editing was completed, a

Table II. Medical History of Subjects by Group

Characteristic Autism (n = 11) (%) DD (n = 10) (%) Typical (n = 11) (%)

Premature (

218 Baranek

prerecorded audio track with an interval timing methodwas superimposed onto the master videotapes. Thisaudio was added to, but did not replace, the sound trackalready on the videotapes. Thus, the raters could hearboth the sounds occurring in the natural context and thedirections for when to score the intervals.

Video Coding ProceduresThe data collection format depended somewhat on

the behavioral category being coded. The general cat-egories of behavior included Looking & Gaze Aver-sion, Affect, Social Touch, Postural Adjustments, Re-sponsiveness to Name, Motor & Object Stereotypies,and Sensory (Tactile, Auditory, Visual, and Vestibu-lar) Modulation. These categories were developed fromthe literature and are summarized in Table HI. The de-tailed coding scale may be found in Baranek (1996).

An interval scoring method was used for the ma-jority of the variables in the categories listed above.One category was coded at a time. There were 20 con-secutive 15-second intervals in each 5-minute segmentof video. For each variable, frequencies were computedacross the 20 intervals. Then, these frequencies wereconverted to rates (i.e., proportion of time behavior wasobserved over each of the two 5-minute segments).Proportion scores have been similarly used in othervideo studies (Grimes & Walker, 1994; Osterling &Dawson, 1994; Walker, Grimes, Davis, & Smith, 1993),and this method allowed a way to control for the rela-tive rate at which children encounter less-frequent sit-

uations. A few remaining variables (e.g., intensity ofaffective expressions; level of object play; sensorymodulation responsiveness/aversion) were quantifiedusing a 4-point rating scale. These scores were recordedas an overall (mean) rating for the video segment. Sincethere were two 5-minute segments for each child, anaverage (mean) score was obtained for each behaviorof interest (either frequency or rating) and used in thefinal statistical analyses.

Interrater ReliabilityTwo raters, blind to the hypotheses of the study,

were trained to use the coding scale and forms. Train-ing was accomplished through a review of the codingscale, followed by viewing of video samples of chil-dren not being used in the study. Interrater reliabilitywas obtained by having the raters score approximately7 to 10 (5-minute) video samples for each behavioralcategory. A conservative measure of interrater relia-bility was used by calculating percentage agreement(for positive instances) for each variable used in inter-val scoring method. Percentage agreement scoresranged from 78 to 100% (for positive instances) for in-dividual variables. Additionally, intraclass correlations(ICCs) were computed for all behavioral categories(both frequency rates and rating scores). The ICC co-efficients were as follow: Affective Expressions (.98),Affect Animation Rating (.88), Anticipatory Postures(.71), Orientation to Auditory Stimuli rates (.80), Au-ditory Responsiveness/Aversion Rating (1.0), Gaze

Table III. Description of Variables Used For Coding

CATEGORY

Affective expressions

LookingGaze aversionResponse to nameSocial touch responsesAnticipatory postureMotor stereotypies

Object stereotypies

Tactile modulation

Auditory modulation

Visual modulation

Vestibular modulation

Description of items

Frequencies of positive and negative expressions (across all intervals); Qualitative rating of range and intensity ofaffective expressions

Frequencies of looking at persons, camera, objects across all intervalsOccurrences of gaze avoidance based on opportunities for face-to-face interactionsProportion of time child responds to name (based on opportunities); Number of prompts given by adultOccurrences of social touch aversion (based on opportunities for physical contact)Frequency of anticipatory postures (reaching) in response to adult gestureFrequencies of repetitive movements of arms and legs; and nonrepetitive unusual movements (e.g., posturing; SIB)

across all intervalsFrequencies of repetitive object interactions (e.g., Twiddle; Tap; Spin; Stare; Line-up; Rub; Mouth objects) across

all intervals; Rating of overall quality/rigidity of object playOccurrences of orientation/attention to (nonsocial) novel tactual stimuli based on opportunities; Tactile

responsiveness/aversion ratingOccurrences of orientation/attention to (nonsocial) novel auditory stimuli based on opportunities; Auditory

responsiveness/aversion ratingOccurrences of orientation/attention to (nonsocial) novel visual stimuli based on opportunities; Visual

responsiveness/aversion ratingOccurrences of orientation to sudden/novel movement stimuli based on opportunities; Vestibular

responsiveness/aversion rating

Autism During Infancy 219

Aversion (.95), Looking Behaviors (.92), Motor Stereo-typies (.92), Object Stereotypies (.95), Object Play rat-ing (.78), Number of Name Prompts (.99), Response toName rates (.98), Social Touch Responses (.95), Ori-entation to Tactile Stimuli rates (.97), Tactile Respon-siveness/Aversion rating (.71), Orientation to Vestibu-lar Stimuli rates (.89), Vestibular Responsiveness/Aversion rating (.88), Orientation to Visual Stimulirates (.92), Visual Responsiveness/Aversion rating (.76).

RESULTS

To explore the usefulness of the individual vari-ables, first descriptive statistics were derived for allvariables by group. Due to limitations inherent in usingthe random video sampling method, two categories(i.e., Vestibular Modulation, Anticipatory Postures)were eliminated, since more than one third of the sub-jects were not videotaped in situations that would elicitthese types of behaviors. Additionally, a few individ-ual variables of interest (e.g, spinning, lining up ob-jects, self-injurious behavior) were excluded since theywere extremely low in frequency (i.e.,

220 Baranek

the resulting function: Mouthing (1.30), Orientation toVisual Stimuli (-1.06), Social Touch Aversions (1.00),Posturing (-0.84), Number of Name Prompts (0.76),and Affect Rating (0.61). Based on the classificationanalysis for the AUT and DD pair only, 9 out of 10 DDchildren and all AUT children were classified correctly,with an overall classification rate of 95%.

DISCUSSION

Infant Markers of Autism

This study confirms that measures of sensory-motorfunctioning, in addition to indicators of social respon-

siveness, have potential as early markers of autism dur-ing infancy. Several sensory-motor deficits were foundto be subtle yet salient at 9 through 12 months in chil-dren with autism. These findings are consistent with otherliterature suggesting that in lieu of the more conventionalmeasures used to detect autism in older children (i.e., de-velopmental milestones; higher language functions;DSM-IV "triad"), sensory-perceptual features may be afruitful avenue to explore in the quest for infant symp-tomatology (e.g., Gillberg et al., 1990; Wing, 1969).

The results also demonstrated that by 9-12 monthsof age, the pattern of behaviors evident in those childrenlater diagnosed with autism was contrastingly differentfrom the patterns displayed by those with delayed or typ-

Table IV. Rates of Individual Behaviors (Descriptive Statistics) and Group Differences

CATEGORYItem

Affective exp.PositiveNegativeAffect rating

LookingPersonsCameraObject

Gaze aversionResponse to name

Rate of responseNo. of prompts/opp

Social touch resp.Motor stereotypies

Repetitive-legsRep.-arms/handsUnusual posturing

Object stereotypiesTwiddle/waveBang/tapMouthingTactile (rubbing)Visual staring/fix.Object play rating

Tactile modulationOrients/registersResp./avers. rating

Auditory modulationOrients/registersResp./avers. rating

Visual modulationOrients/registers

AUT

M SD

0.480.062.2

0.320.580.630.03

0.681.100.10

0.060.160.11

0.050.060.180.030.012.41

0.801.86

0.782.2

0.62

0.140.100.56

0.180.190.130.06

0.351.370.16

0.100.080.13

0.020.050.150.060.020.80

0.290.40

0.210.17

0.35

DD

M SD

0.400.021.65

0.380.380.670.03

0.740.450.02

0.070.150.14

0.050.030.090.010.061.55

0.872.22

0.632.18

0.86

0.150.030.71

0.160.220.150.03

0.320.510.03

0.050.140.05

0.070.020.090.010.100.83

0.160.56

0.180.17

0.14

TYP

M SD

0.490.052.18

0.250.600.660.01

0.710.210.01

0.030.110.05

0.080.090.080.010.012.41

0.882.15

0.752.28

0.81

0.190.040.64

0.060.230.110.02

0.31170.02

0.050.080.04

0.090.090.070.030.010.49

0.200.57

0.190.20

0.16

df

2, 292, 292, 29

2, 292, 292, 292, 29

2, 292, 292, 29

2, 292, 292, 29

2, 292, 292, 292, 292, 292, 29

2, 262, 26

2, 272, 27

2, 28

F

0.980.972.60

2.323.37b0.240.73

0.092.89*2.71

0.910.743.14*

0.881.852.831.612.67a4.89C

0.341.21

1.251.36

2.85aResp./avers. rating 2.33 0.38 2.38 0.25 2.57 0.36 2, 28 1.19

a p < .10.

b p < .05.

c p

Autism During Infancy 221

ical development on a combination of nine variables.See Table VI for a summary of these contrasting pat-terns and the individual behaviors comprising those pat-terns. These nine variables predicted group membershipat high rates (93.75%) and thus, may be helpful in fu-ture research of early assessment/differential diagnosis.It appears premature, however, to use these items as ascreening tool until they can be cross-validated in futureretrospective as well as prospective studies.

Furthermore, this research suggests that aspectsof sensory-motor functioning should be used to augmentbut not replace measures of social responsiveness (e.g.,joint attention, showing, social interest), which havebeen proven to be valid and critical for detection ofautism in young children after the first year of life(Baron-Cohen et al., 1996; Lord, 1995; Osterling &Dawson, 1994). This study confirms previous researchthat children with autism show delays/deficits in theirability to respond to attention-getting strategies (e.g.,calling child's name) used by parents of children acrossvarious age groups (Adrien el al., 1993; Lord, 1995;

Osterling & Dawson, 1994). This particular behavior(Responsiveness to Name) thus may be particularly use-ful as a predictor across age groups in young childrenwith autism. Although these findings are congruent witha hypothesis that young children with autism have dif-ficulty orienting to social stimuli (Osterling & Dawson,1994), they also raise the possibility that children withautism have more general problems with responsiveness(orientation/attention) to all types of sensory stimuli. Infact, the group of infants with autism in this study tendedto have attenuated levels of Orientation to Visual Stim-uli, a finding previously documented in older children(O'Connor & Hermelin, 1967). Additionally, other sen-sory-motor markers found useful in this study (e.g.,Mouthing Objects) do not appear to be attributable todeficits in social responsiveness per se, while others(e.g., Social Touch Aversions, Name Prompts) seemedto cross the social/nonsocial distinction. One interpre-tation of these findings may be some symptoms ofautism during infancy reflect more pervasive deficits insensory attention or arousal modulation mechanisms thatsubserve both categories of behavior (social and nonso-cial). Such limited capacities in arousal modulation andinformation processing have been implicated previously(Dawson & Lewy, 1989; Ornitz, et al., 1977). Furtherstudy is needed to determine whether or not deficits insensory processing (e.g., orientation to nonsocial stim-uli or touch aversions) may serve as precursors to diffi-culties in other, more socially directed behaviors (e.g.,joint attention, social withdrawal) that are known to beproblematic in children with autism after 12 monthsof age (Baron-Cohen et al., 1996; Lord, 1995; Sigmanet al., 1986). Alternately, more research is also neededto determine whether unusual sensory responses in in-fancy may be a function of limited social awareness.

Table V. Frequency and Percentage of Subjects ClassifiedCorrectly from Discriminant Analysis"

Actual GroupMembership

Classified Classified Classifiedas as as

autism DD/MR typical

n % n % n %

Autism (= 11) 10 90.9 0 0 1 9.1DD/MR (n =10) 1 10 9 90 0 0Typical (n = 11) 0 0 0 0 11 100a Total percentage of "grouped" cases correctly classified: 93.75%.

Table VI. Patterns Differentiating Autism, DD and Typical Subjects at 9-12 Months of Agea

Infant Symptoms Autism profile DD profile Typical profile

Function 1: Autism symptomsPoor visual orientation/attention (nonsocial)Prompted/delayed response to nameExcessive mouthing of objectsSocial touch aversions

Function 2: DD/MR symptomsStereotyped quality to object playUnusual posturing of body partsDiminished looking at cameraVisual staring/fixation on objectsLess animated affective expressions

High

Moderately low

Low

High

Low

Low

" Autism Group: More vulnerable to deficits on Function 1 than Function 2 behaviors; DD group: More vulnera-ble to deficits on Function 2 than 1 ; Typical group: Low vulnerabilities on both.

222 Baranek

Less clear is why some of the social measures in-vestigated in this study were not useful to discriminatethe groups. Contrary to expectations, the children withautism in this study had frequencies of positive and neg-ative affect that were comparable to the other twogroups. The finding that the DD group had less anima-tion in affective expressions, however, is consistent withother studies of children with Down syndrome (Brooks-Gunn & Lewis, 1982).

In contrast to findings by Osterling and Dawson(1994), Looking at Persons was not found to be a sig-nificant indicator of autism during infancy, even thoughthe situations studied were similar (i.e., videos of fam-ily events). One caveat is that eye contact is difficultto judge accurately from video since it is sometimesdifficult to see all persons simultaneously, and this dif-ficulty may have contributed to discrepant findings.Perhaps, some types of social deficits may be depend-ent upon developmental progressions before they be-come apparent in autism (i.e., after 12 months of age).It is also possible that Looking at Persons in isolationof contextual variables is not consistently or specifi-cally deficient in children with autism. Studies witholder autistic children have documented that the amountof looking does not necessarily differentiate childrenwith autism from other groups during structured socialinteractions (Dawson et al., 1990; Sigman et al., 1986).

Alternately, it is possible that group differences inlooking behaviors may have been overshadowed by theoverly social nature of children with Down syndromethat were predominant in the DD group. For example,children with Down syndrome have demonstrated apreference for social stimuli (i.e., faces) (Kasari, Mundy,Yirmiya, & Sigman, 1990) and a greater number of joint-attention behaviors as compared to developmentallymatched typical peers (Franco & Wishart, 1995; Lewy& Dawson, 1992). Caution must be taken in generaliz-ing the findings from the present study beyond thosechildren with mental retardation specifically associatedwith Down syndrome.

In contrast to Lord's (1995) study of preschoolers,overall measures of stereotypies (which are consideredas a critical feature of autism in conventional diagnosis)were not useful as predictors of autism at 9-12 monthsof age in the present study. Perhaps, stereotypies mayalso be dependent on developmental changes that af-ford more advanced perceptual-motor abilities. This in-terpretation is consistent with evidence that stereotypiesintensify and become more obvious from approximately2-5 years of age (Lord, 1995; Losche, 1990). On theother hand, most simple repetitive movements are souniversal during infancy (Thelen, 1981) that atypicalmanifestations are difficult to differentiate at this early

stage. One stereotypy, Mouthing Objects, however, diddiscriminate the children with autism in this study.Thus, there may be a window of opportunity for the use-fulness of particular measures; and, it would be impor-tant to trace whether such an early behavioral manifes-tation of stereotypy (i.e., mouthing) is a precursor oflater-evolving forms within the same general class.

However, it is important to reiterate that the chil-dren with DD were identified at a similarly high rateto the group with autism in this study. Although someof the variables (e.g., affect, visual fixation) originallywere included in an effort to identify autism specifi-cally, they were actually found to reflect better thosewith general developmental disabilities.

Compensatory Techniques By Caregivers:Clues to Earlier Assessment?

The early markers of autism (both sensory-motorand social) revealed in this study were evident on videoprior to the age that parents in the study began to sus-pect problems. This finding is consistent with reportssuggesting that a parent's awareness of symptoms de-pends on the child's developmental stage and the de-gree to which symptoms deviate from normal devel-opment (Lord, 1995; Stone & Hogan, 1993). However,caregivers in this video study were additionally foundto use compensatory strategies in an effort to engagetheir children more successfully in social interactionsand playeven though they were not cognizant of thechild's subtle deficits. These results echo similar find-ings with other age groups (e.g., Adrien et al., 1992)and suggest that caregivers act to maximize their chil-dren's success during social interactions. It is signifi-cant to note that the children with autism did respondwhen given time and appropriate structure; however,repeated prompting was necessary to bring about thedesired response. Parents seemed to be increasing thesaliency or meaning of a given stimulus through repet-itive cuinga finding that is consistent with the notionthat sensory-attentional mechanisms may be disruptedin infants with autism. Thus, the present study demon-strates that parent's compensatory behaviors may pro-vide a reflection of autistic symptoms during infancy,and a means by which to develop useful measures forearlier identification and intervention.

Retrospective Video Analysis: Strengths,Limitations and Future Research

This study validates previous findings that retro-spective video analysis is an effective tool with whichto study young children with autism (e.g., Adrien et al.,

Autism During Infancy 223

1993; Losche, 1990; Osterling & Dawson, 1994). Thismethod provides a window into these earliest manifes-tations of autistic symptomatology within a naturalisticparadigm; however, it is not without significant con-straints and challenges which include the extraordinaryamounts of time, technical support needed, and expensesincurred. These are often the things that are in short sup-ply for clinicians and early interventionists, who mightbe the very persons interested in using alternative meth-ods for early diagnosis. Furthermore, video samples mayalso be a narrow representation of children's behaviors.That is, parents preselect the situations that favor pleas-ant situations and special achievements and avoid video-taping children during uneventful, unpredictable, or ad-verse conditionsa process that may obscure certainsymptoms.

Other limitations of this study include the rater'spotential awareness of distinguishing features of Downsyndrome that may have influenced their perceptionsduring coding, and the relatively small sample since itwas difficult to collect large numbers of families withgood video records of their children's early development.Likewise, sampling a range of situations in 10 minutesprovided a cross-section of age and behavior but did notallow for the detailed analyses of infrequent or context-specific situations. For example, some behaviors such asaffective responses may need to be measured within spe-cific social contexts or perhaps in tandem with other so-cial responses (e.g., smiling while looking at person) inorder to evidence atypicalities at this age. Further re-search is needed to determine the effects of various con-texts on the specific behaviors of interest in this studyand to compare results to other diagnostic groups thathave less distinguishing features.

ACKNOWLEDGMENTS

I extend my gratitude to the families that partici-pated in this study and organizations that provided as-sistance, especially Lutheran General DevelopmentalPediatrics, University of Chicago Department of ChildPsychiatry, Waisman Center, Autism Society of Illi-nois, and the Ameritech Corporation Visual Commu-nications Department. Special thanks to Laura Sher-petis, Priti Gandhi, Eden Opsahl, Teresa Moran, andPaul Frellick for their technical contributions, and toMarji Getz and Margaret Creedon for their helpful sug-gestions. Partial funding for this project was receivedfrom NICHD Grant 27184, the AOTA and APA Dis-sertation Awards. I am most grateful to Gershon Berk-son and Cathy Lord for their expertise, mentorship, andtremendous support throughout this 4-year project.

REFERENCES

Adrien, J. L., Barthelemy, C., Perrot, A., Roux, S., Lenoir, P.,Hameury, L., & Sauvage, D. (1992). Validity and reliability ofthe infant behavioral summarized evaluation (IBSE): A ratingscale for the assessment of young children with autism and de-velopmental disorders. Journal of Autism and DevelopmentalDisorders, 22, 375-394.

Adrien, J. L., Lenoir, P., Martineau, J., Perrot, A., Hameury, L.,Larmande, C., & Sauvage, D. (1993). Blind ratings of earlysymptoms of autism based upon family home movies. Journalof the American Academy of Child and Adolescent Psychiatry,32, 617-626.

Adrien, J. L., Ornitz, E., Barthelemy, C., Sauvage, D., & LeLord, G.(1987). The presence or absence of certain behaviors associ-ated with infantile autism in severely retarded autistic and non-autistic retarded children and very young normal children. Jour-nal of Autism and Developmental Disorders, 17, 407-416.

American Psychiatric Association. (1994). Diagnostic and statisticalmanual of mental disorders (4th ed.). Washington, DC: Author.

Bailey, A., Phillips, W., & Rutter, M. (1996). Autism: Towards anintegration of clinical, genetic, neuropsychological and neuro-biological perspectives. Journal of Child Psychology and Psy-chiatry, 37, 89-126.

Baranek, G. T. (1996). Early predictors of autism using retrospectivevideo analysis. Doctoral dissertation, University of Illinois atChicago. (UMI Microform No. 9713247)

Baron-Cohen, S., Cox, A., Baird, G., Swettenham, J., Nightingale, N.,Morgan, K., Drew A., & Charman, T. (1996). Psychological mark-ers in the detection of autism in infancy in a large population.British Journal of Psychiatry, 168, 158-63.

Brooks-Gunn, J., & Lewis, M. (1982). Affective exchanges betweennormal and handicapped infants and their mothers. In T. Field &A. Fogel (Eds.), Emotion and interaction (pp.161-188). Hillsdale,NJ: Erlbaum.

Dahlgren, S. O., & Gillberg, C. (1989). Symptoms in the first twoyears of life: A preliminary population study of infantile autism.European Archives of Psychiatric and Neurological Science,238, 169-174.

Dawson, G., Hill, D., Spencer, A., Galpert, L., & Watson, L. (1990).Affective exchanges between young autistic children and theirmothers. Journal of Abnormal Child Psychology, 18, 335-345.

Dawson, G., & Lewy, A. (1989). Arousal, attention, and the socioe-motional impairments of individuals with autism. In G. Dawson(Ed.), Autism: Nature, diagnosis, and treatment (pp. 49-74).New York: Guilford.

Field, T. (1981). Infant arousal, attention, and affect during early in-teractions. Journal of the American Academy of Child Psychia-try, 20, 308-317.

Franco, F., & Wishart, J. (1995). Use of pointing and other gesturesby young children with Down syndrome. American Journal onMental Retardation, 100, 160-182.

Gillberg, C., & Coleman, M. (1992). The biology of the autistic syn-dromes (2nd ed.). London: MacKeith.

Gillberg, C., Ehlers, S., Schaumann, H., Jakobsson, G., Dahlgren, S.,Lindblom, R., Bagenholm, A., Tjuus, T., & Blidner, E. (1990).Autism under age 3 years: A clinical study of 28 cases referredfor autistic symptoms in infancy. Journal of Child Psychologyand Psychiatry, 31, 921-931.

Grimes, K., & Walker, E. F. (1994). Childhood emotional expres-sions, educational attainment, and age at onset of illness in schiz-ophrenia. Journal of Abnormal Psychology, 103, 784-790.

Kanner, L. (1943). Autistic disturbances of affective contact. Ner-vous Child, 2, 217-250.

Kasari, C., Mundy, P., Yirmiya, N., & Sigman, M. (1990). Affectand attention in children with Down syndrome. American Jour-nal on Mental Retardation, 95, 55-67.

Lewy A. L., & Dawson, G. (1992). Social stimulation and joint at-tention in young autistic children. Journal of Abnormal ChildPsychology, 20, 555-566.

224 Baranek

Lord, C. (1995). Follow-up of two-year-olds referred for possibleautism. Journal of Child Psychology and Psychiatry, 36,1365-1382.

Lord, C., Rutter, M, & LeCouteur, A. (1994). Autism Diagnostic In-terview-Revised: A revised version of the autism diagnostic in-terview for caregivers of individuals with possible pervasive de-velopmental disorders. Journal of Autism and DevelopmentalDisorders, 19, 363-187.

Losche, G. (1990). Sensorimotor and action development in autisticchildren from infancy to early childhood. Journal of Child Psy-chology and Psychiatry, 31, 749-761.

Massie, H. N. (1977). Patterns of mother-infant interaction in homemovies of prepsychotic and normal infants. American Journalof Psychiatry, 135, 1371-1374.

O'Connor, N., & Hermelin, B. (1967). The selective visual attentionof psychotic children. Journal of child Psychology and Psychi-atry, 8, 167-179.

Ornitz, E. M., Guthrie, D., & Farley, A. H. (1977). The early devel-opment of autistic children. Journal of Autism and ChildhoodSchizophrenia, 7, 207-229.

Osterling, J., & Dawson, G. (1994). Early recognition of childrenwith autism: A study of first birthday home videotapes. Jour-nal of Autism and Developmental Disorders, 24, 247-257.

Rosenthal, J., Massie, H. N., & Wulff, K. (1980). A comparison ofcognitive development in normal and psychotic children in thefirst two years of life from home movies. Journal of Autism andDevelopmental Disorders, 10, 433-443.

Rutter, M., & Schopler, E. (1987). Autism and pervasive develop-mental disorders: Concepts and diagnostic issues. Journal ofAutism and Developmental Disorders, 17, 159-186.

Schopler, E., Reichler, R. J., & Renner, B. R. (1988). The Child-hood Autism Rating Scale. Los Angeles: Western PsychologicalServices.

Sigman, M., Mundy, P., Sherman, T., & Ungerer, J. (1986). Socialinteractions of autistic, mentally retarded, and normal childrenand their caregivers. Journal of Child Psychology and Psychi-atry, 27, 647-656.

Sparrow, S. S., Balla, D. A., & Cicchetti, D. V. (1984). VinelandAdaptive Behavior Scales. Circle Pines, MN: American Guid-ance Service.

Stone, W. L., & Hogan, K. L. (1993). A structured parent interviewfor identifying young children with autism. Journal of Autismand Developmental Disorders, 23, 639-652.

Stone, W. L., Lemanek, K. L., Fishel, P. T., Fernandez, M. C., & Alt-meier, W. A. (1990). Play and imitation skills in the diagnosisof young autistic children. Pediatrics, 86, 267-272.

Thelen, E. (1981). Kicking, rocking, and waving: Contextual analy-sis of rhythmical stereotypies in normal human infants. AnimalBehavior, 29, 3-11.

Volkmar, P., Stier, D., & Cohen, D. (1985). Age of recognition of per-vasive developmental disorders. American Journal of Psychiatry,142, 1450-1452.

Walker, E. F., Grimes, K. E., Davis, D. M., & Smith, A. J. (1993).Childhood precursors of schizophrenia: Facial expressions ofemotion. American Journal of Psychiatry, 150, 1654-1660.

Watson, L., & Marcus, L. (1988). Diagnosis and assessment of pre-school children. In E. Schopler & G. Mesibov (Eds.), Diagnosisand assessment in autism (pp. 271-301). New York: Plenum Press.

Wing, L. (1969). The handicaps of autistic children: A comparativestudy. Journal of Child Psychology and Psychiatry, 10, 1-40.