An Investigation of Attention and Affect In

Journal of Autism and Developmental Disorders, Vol. 27, No. 4, 1997

An Investigation of Attention and Affect inChildren with Autism and Down Syndrome

Robert M. Joseph and Helen Tager-Flusberg1

University of Massachusetts at Boston

Longitudinal videotape recordings of six young children with autism and six age-and language-matched children with Down syndrome in structured play with theirmothers at home were coded for the focus of the child's visual attention for fourbimonthly visits and for facial affect for two of the four visits. The main findingwas that the children with autism showed reduced expression of positive affect ina familiar social context. The autistic group attended to the mother's face andthe researchers only about half as much as the Down syndrome group, but thesedifferences did not reach statistical significance. Compared to the Down syndromegroup, the autistic group displayed a smaller proportion of their total positive affecttoward the mother's face and toward the researcher, but only the latter groupdifference reached statistical significance. Although limited by the small samplesize, these findings suggest that autistic children's known deficits in attention andaffective responsiveness to others persist even in structured interactions with afamiliar partner in the home.

Children with autism are fundamentally impaired in their ability to initiateand maintain interactions with other people. Their abnormalities in visualattention and specifically in eye-to-face gaze have long been cited as a keyfacet of their social impairment (Mirenda, Donnellan, & Yoder, 1983; Rut-ter, 1978; Wing, 1976). Early experimental evidence has suggested that chil-dren with autism avoid eye contact with others (Hutt & Ounsted, 1966;Richer & Coss, 1976) and specifically lack the ability to use shifts of gazefrom a person's face to an object for the purpose of establishing sharedattention (Mundy, Sigman, Ungerer, & Sherman, 1986). Nevertheless,

1Address all correspondence to Helen Tager-Flusberg, University of Massachusetts—Boston,Department of Psychology, 100 Morrissey Boulevard, Boston, Massachusetts 02125-3393.

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0162-3257/97/0800-0385$12.50/0 © 1997 Plenum Publishing Corporation

many recent studies observing children with autism in a variety of socialsituations with familiar and unfamiliar adults have shown that they attendto the faces of their social patterns no less than comparison groups(Dawson, Hill, Spencer, Galpert, & Watson, 1990; Kasari, Sigman, Mundy,& Yirmiya, 1990; Sigman, Mundy, Sherman, & Ungerer, 1986). There isalso substantial evidence that structured interactions enhance autistic children'sattention to the face of their social partner relative to the amount they attendto the face of another person in an unstructured social situation (Dawson &Galpert, 1990; Kasari, Sigman, & Yirmiya, 1993; Volkmar, Hoder, & Cohen,1985; Vokmar & Mayes, 1990). As Kasari et al. (1993) have argued, the or-ganization and guidance provided by adults interacting with autistic childrenappears to serve a supportive or scaffolding function (Vygotsky, 1978) thatenhances the autistic child's otherwise deficient social skills.

The marked lack of affective responsivity to other people among chil-dren with autism is another major facet of their social impairment that hasbeen noted since the syndrome was first identified by Kammer (1943). Re-search has confirmed that children with autism display significantly loweramounts of positive affect expressed while looking at others (Dawson etel., 1990; Snow, Hertzig, & Shapiro, 1987; Bernstein, Shapiro, & Hertzig,1993) and in the context of joint attention situations (Kasari, Sigman, etal., 1990), suggesting that they are fundamentally impaired in the normalability to use positive affective displays to establish and regulate interper-sonal interaction (e.g., Adamson & Bakeman, 1985; Tronick, 1989). How-ever, these findings are based on play interactions that were not specificallystructured or that were conducted with an unfamiliar adult in a laboratorysetting. Consequently, it remains a question whether autistic children's defi-cits in affective sharing would persist in the highly supportive social contextof a structured interaction with a familiar social partner.

The present study was an observational investigation of attention andaffect in children with autism and Down syndrome in a home setting withfamiliar caretakers, over time. The main aim of the study was to see if autisticchildren's attention and affective responsiveness to others would benefit fromthe optimally supportive context of a structured interaction with a familiarperson in a familiar environment. Given that prior research has consistentlyshown deficits in autistic children's affective relatedness to other people, wewere particularly interested in whether the scaffolding effect that a structuredcontext has been shown to have on autistic children's attention to othersmight extend to their affective responsiveness to people as well. To explorethis, we focused on an episode during which the child was presented with agift by the researchers. Mothers were asked to help the child open the giftand play with it with their child for several minutes. Observations of the tapesacross subjects and visits confirmed that this episode represented a highly

Joseph and Tager-FIusberg386

structured and familiar interaction between the mother and child. Mothershelped the child to open the gift, thank the researchers, and supervised initialplay in a consistent pattern of controlled interactions.

A second aim of this study was to explore developmental trends in at-tention and affect over time. Given that we were examining children's atten-tion and affective responsivity to the faces of their social partners as a markerof their social competence, we were particularly interested in whether eitherof these behaviors would show increases over time, particularly as the pro-cedures and the events became more familiar to the children.

METHOD

Subjects

The data examined in this study were collected previously for a lon-gitudinal study on language acquisition in children with autism (Tager-Flus-berg et al., 1990). Subjects included six children diagnosed as autisticaccording to DSM-III-R (American Psychiatric Association, 1987) criteria.These subjects had all received this diagnosis from either a psychiatrist orneurologist. Furthermore, at the time they entered the study a behaviorchecklist was completed, that included items from the DSM-III-R, to con-firm that the children met the criteria. The autistic subjects were all males,living at home with their biological families, and either participating inhome-based intervention programs or special day-school programs. Theirsocioeconomic status ranged from lower to upper middle class. Becausethe data were originally collected for a study on language acquisition, theautistic subjects were selected for having already acquired some language.The IQs of the autistic subjects were assessed using the Leiter (1974) In-ternational Performance Scale. Although the autistic sample was not spe-cifically selected for higher levels of cognitive functioning, four of the sixchildren scored in the normal or low-normal range of nonverbal IQ.

The comparison group included six children with Down syndrome(DS). The DS group included four boys and two girls who were locatedthrough hospital records and who shared similar family, educational, andsocioeconomic backgrounds with the autistic children. The children withDS were specifically selected to match the autistic children on chronologicalage and language level, as measured by mean length of utterance (MLU)at the start of the original longitudinal study. The children with DS, how-ever, were not matched to the autistic children on nonverbal IQ. Charac-teristics of the autistic and DS group are detailed in Table I.

T tests confirmed that the autistic and DS groups were well-matchedon age, t(10) = 0.30, and MLU, t(10) = 0.21, at the beginning of the study,

Attention and Affect 387

Table I. Subject Characteristics

Age (months)MSD

IQh

MSD

MLUMSD

Autistic

63.720.8

89.0a

16.5

2.270.96

Down syndrome

60.514.7

54.0a

7.5

2.170.76

aSignificant difference between group means; p <.001.

bAs measured on the Leiter International Perform-ance Scale.

and that the autistic subjects had significantly higher nonverbal IQs, t(10)= 4.32, p < .001.

Procedures

Two researchers visited the children's homes every other month over thecourse of 12 to 24 months. After videotaping equipment was set up, themother and child were invited to start playing together.2 The researchers re-mained uninvolved in the ongoing interaction and only responded brieflywhen spoken to. During each 60-minute session, one of the researchers gavethe child a wrapped gift Mothers were asked to help the child to exploreand play with the new toy. Gifts included crayons, sticker books, play dough,and puzzles. The opening of the toy gift and the play between mother andchild that ensued served to establish a comparable, semistructured period ofsocial interaction across subjects and visits. The 6-minute period ofvideotaped interaction following the child's receipt of the gift was the focusof this study. The two groups of children were compared on their attentionto objects, their mothers, and the researchers over the course of four visitsto their homes and, for two of the four visits, on their facial affect and itsrelationship to the focus of their attention.

Coding and Measures

All data were coded by one researcher directly from a VCR to a com-puter (Arcus, Snidman, Campbell, Brandzel, & Zambrano, 1991). The com-puter board linking the VCR and computer permitted keyboard control of

2In one visit a child was observed interacting with his father rather than his mother.


the VCR and direct entry of behavioral codes and their associated framenumbers into the computer. When entered, the codes were stored in theorder of their frame numbers and written to an ASCII file which could bereviewed and edited in subsequent viewings. Each child's behavior duringthe 6-minute period following the receipt of the gift was coded continuouslyfor focus of attention and facial affect.

Attention. Attention was coded for four consecutive bimonthly visits.In 8 of the 48 visits coded for attention, a 4-month rather than a 2-monthperiod elapsed from the time of the previous coded visit. The lighting, fo-cus, and/or camera position in the videotaped recordings of the interviewingvisits was judged to make the tapes too difficult to code reliably. The ex-tended intervals between visits were evenly distributed between the autisticand DS groups. Attentional focus was coded in terms of five mutually ex-clusive categories: (a) mother's face; (b) researchers; (c) mother-supportedobjects (an object or set of objects that was being held, touched, or ma-nipulated by the mother); (d) nonsupported objects; and (e) unfocused (noapparent focus of visual attention). Coding of attention to mother's facerevealed that on several occasions mothers gained their child's attentiontoward their faces by physically redirecting the child's gaze (e.g., by liftingthe child's chin). Subsequently, attention to the mother's face was recoded,resulting in an adjusted measure of attention to the mother's face whichexcluded those occasions on which mothers physically directed the child'sattention to their faces.

Affect. Facial affect was coded for two of the four visits coded for at-tention. The two visits were selected on the basis of independent judgmentsof videotaping conditions (lighting, focus, camera position) that wouldmaximize reliability in the coding of the affect variable. The time interven-ing between visits coded for emotion ranged from 4 to 10 months with amean of 5.7 months for autistic group, and ranged from 4 to 8 monthswith a mean of 5.7 months for the DS group. The coding scheme for facialaffect was adapted from Bloom, Beckwith, Capatides, and Hafitz (1988).It consisted of four categories: (a) neutral/interested; (b) negative; (c) posi-tive; and (d) mixed (positive and negative) or ambiguous. Positive affectivedisplays were simultaneously coded for the focus of visual attention: (a)mother's face; (b) researchers; (c) mother-supported objects; (d) nonsup-ported objects; and (e) unfocused. For both the attention and affect vari-ables, there were two additional categories used when the child's behaviorcould not be coded: (a) camera off (the position of camera makes the at-tentional focus or affective expression unclear); and (b) leaves interaction(the child temporarily leaves the interaction).

Interrater Reliability. Reliability was determined by having an independentobserver code a randomly selected portion of one visit for each subject equal


to 10% of the total time coded across the four visits. Kappa values for interrateragreement ranged between .85 and 1.0 with a mean value of .94.

RESULTS

Attention

A mean total of 6.41 and 6.44 minutes of videotape were coded pervisit for the autistic and DS groups, respectively. T tests of group meansrevealed no significant difference in the amount of time children spent awayfrom their mothers. After these two sums were subtracted from the totaltime coded, there remained a mean of 5.82 and 6.02 minute of interactionfor the autistic and DS subjects, respectively.

To correct for the small differences in the absolute amount of timecoded for attention for each visit, the amount of time spent in each categoryof attention was calculated as a proportion of the total amount of timecoded for attention. These proportional figures were then subjected toarcsine transformation (Winer, 1971) in order to meet the variance assump-tions of an analysis of variance.

A mixed two-factor ANOVA with group as the between-subjects vari-able and time as the within-subjects variable was run on each attentionvariable. These analyses revealed no significant main effect of group forany of the attention categories.

Table II displays the mean percentage of time each group spent ineach attention category, based on the total of four visits. Whereas four ofthe mothers of the autistic children used physical means to gain attentionto their faces on 23 occasions, on only one occasion did one of the mothersof the DS children physically redirect her child's gaze toward her face. Ascan be seen in Table II, after the times during which mothers physicallymanipulated the child's attention toward their faces were subtracted, theresulting adjusted measure of attention to the mother's face showed a

Table II. Mean Percentage of Time in Each Category of Attention

Autistic

Category

Mother's faceMother's face (adjusted)Mother-supported objectsNonsupported objectsResearchersUnfocused

M

3.83.3

48.041.62.64.0

SD

2.82.7

13.617.81.34.0

Down syndrome

M

6.06.0

45.740.75.71.7

SD

3.73.77.9

14.74.61.4

Joseph and Tager-Flusberg390

larger group difference, but this difference still did not reach statistical sig-nificance. The occasions on which mothers physically directed attention totheir faces were excluded from the remaining analyses of the attention data.

Additional mixed-model ANOVAs on the mean duration (in seconds)and frequency (per minute) of each category of attention also showed nomain effect of group for any of the attention variables. However, a groupdifference in the frequency of attention to the mother's face per minuteapproached significance, F(1, 10) = 3.62, p < .10, with means of 1.32 and2.46 for the autistic and DS groups, respectively. In contrast, there wasvirtually no group difference in mean duration of attention to the mother'sface, with means of 1.37 and 1.36 seconds for the autistic and DS groups,respectively.

None of the analyses showed a significant effect of time for theamount, frequency, or mean duration of any of the attention variables.However, there was a nearly significant, F(3, 30) = 2.78, p < .06, increasein the amount both the autistic and DS groups attended to their mother'sfaces over the course of the four visits.

Affect

A mean of 6.97 and 5.97 minutes of interaction time per visit werecoded for facial affect in the autistic and DS groups, respectively. For 24%of the total time coded for each group, either the child leaving the inter-action or the position of the camera prevented coding of facial affect.Elimination of these data left a mean of 5.30 and 4.51 minutes of codedinteraction time per visit for the autistic and DS groups, respectively. Aswith the analysis of the attention data, differences in the absolute amountof time coded for affect were corrected by calculating the amount of timespent in each category of affect as a proportion of the total amount oftime coded for affect, and the proportional figures were subjected toarcsine transformation. Mixed two-way ANOVAs with group as the be-tween-subjects variable and time as the within-subjects variable were con-ducted for the amount, frequency, and mean duration of each category ofaffect as well as each subcategory of positive affect.

As can be seen in Table III, children with autism spent a significantlysmaller proportion of interaction time in positive affect than did the DSchildren, F(l, 10) = 5.66, p < .05. Conversely, the autistic group was ob-served to appear neutral or interested for a significantly greater proportionof the time than the DS group, F(1, 10), p < .05. Both autistic and DSchildren displayed relatively small amounts of negative and mixed/ambigu-ous affect, with no significant differences between groups. Analyses of thefrequency and mean duration of children's displays of positive, neutral, and


negative affect showed that autistic children displayed positive affect sig-nificantly less often than the DS children, F(1, 10) = 7.98, p < .02, withgroup means of 2.88 (SD = .84) and 7.56 (SD = 3.96) positive affect dis-plays per minute.

As displayed in Table IV. analyses of the amount of positive affect chil-dren exhibited in relation to each attentional referent showed that theautistic group displayed significantly less positive affect than the DS grouptoward the mother's face, F(1, 10) = 5.01, p = .05, the researchers, F(l,10) = 9.76, p < .02, and nonsupported objects, F(l, 10) = 5.44, p < .05.

Because the autistic group showed less overall positive affect than theDS group, the amount of positive affect toward each attentional referentwas also analyzed as a proportion of the total time in positive affect, which,as shown in Table V, resulted in only one significant difference betweengroups. Autistic children spent a significantly smaller proportion of theirtotal time in positive affect displaying positive affect toward the researchers,F(l, 10) = 8.03, p < .02.

There were no significant group differences in the mean duration ofpositive affective displays toward the various attentional referents, but therewere significant group differences in the frequency (per minute) of two ofthe categories of positive affect. The autistic children displayed positive af-

Table IV. Each Category of Positive Affect as a Percentage of TotalTimea

Autistic Down syndrome

Category

Mother's faceMother-supported objectsNonsupported objectsResearchersUnfocused

M SD

0.8b 0.87.8 7.04.3* 3.60.4* 0.80.5 0.5

M SD

2.3* 1.77.3 4.79.1* 4.63.8* 3.71.6 2.1

"Statistics are based on arcsine transformations of proportional data.bSignificant difference between group means; p < .05.


Table III. Mean Percentage of Time in Each Category of Affecta

Category

Neutral/interestedPositiveNegativeMixed/ambiguous

Autistic

M SD

85.0b 5.913.8* 7.01.2 1.50.3 0.4

Down syndrome

M

75.4*24.3*0.30.0

SD

9.79.60.40.0

"Statistics are based on arcsine transformations of proportional data.bSignificant difference between group means; p < .05.

Attention and Affect

fect toward the researchers and nonsupported objects significantly lessoften than did the DS children, F(1, 10) = 6.25, p < .05 and F(l, 10) =7.89, p < .02, respectively. Autistic children's less frequent display of posi-tive affect toward their mothers' faces approached significance, F(l, 10) =3.77, p < .10. None of the analyses showed a significant effect of time onchildren's affective behavior across the two visits.

DISCUSSION

In the context of a semistructured social interaction in the home inwhich children were assisted by their mothers in playing with a new toy,children with autism showed an overall pattern of attention similar to thatof a comparison group of children with Down syndrome. However, the lackof significant differences in attention between groups needs to be inter-preted cautiously given the small sample, the large amount of variabilityamong subjects, and the subsequent possibility of a Type II error. In fact,the autistic group spent only about half as much time as the DS groupattending to their mothers' faces and to the researchers. In addition, moth-ers of children with autism on many occasions physically directed their chil-dren to look at them, a behavior that was virtually absent in the DS group.These observations suggest that the children with autism were impaired intheir ability to use eye contact to facilitate social interactions and, further,that their deficits in social attention were not offset by the supportive socialcontext provided by their mothers. These findings are inconsistent withprior research showing that children with autism attend to the faces of theirsocial partners no less than control subjects (Dawson et al., 1990; Kasari,Sigman, et al., 1990; Sigman et al., 1986), especially when the interactionis structured and guided by an adult (Kasari et al., 1993). One possibleexplanation for this inconsistency is that the interactions examined in thepresent study, organized around the receipt and exploration of a new toy,

393

Table V. Each Category of Positive Affect as a Percentage of TotalTime in Positive Affecta

Category

Mother's faceMother-supported objectsNonsupported objectsResearchersUnfocused

Autistic

M SD

8.6 11.342.3 27.840.1 28.74.1b 5.64.8 4.6

Down syndrome

M SD

14.9 16.127.8 14.736.9 18.016.2* 12.84.2 5.1

aStatistics are based on arcsine transformations of proportional data.bSignificant difference between group means; p < .05.

may have been specifically pulling for joint attention behaviors, includingshifting of gaze between object of shared attention and social partner, inwhich children with autism have been found to be particularly lacking(Mundy et al., 1986). Eye-to-face gaze has been observed to serve severalimportant regularly functions in human interactions, such as initiating orterminating an interaction sequence (Knapp, 1980), indicating an interestin an object of shared attention (Bakeman & Adamson, 1984), and refer-encing a person's reaction (Feinman, 1982). Both the autistic and Downsyndrome children in this study showed an increasing amount of attentionto their mothers' faces across the four visits to their homes, suggesting thatattention to the mother's face is indeed an important marker of social andcommunicative development in these groups.

The children with autism exhibited significantly less overall positiveaffect than did the children with Down syndrome, particularly toward theresearchers. This finding is interesting in that the researchers, in contrastto the mothers, never attempted to engage any of the children in socialinteraction. Thus, it appears that in a situation in which the autistic childrenwould have been required to initiate a social interaction, they were par-ticularly lacking in affective responsivity toward others.

The lack of other significant group differences in affective behavioragain raises concern about the small sample and inadequate statisticalpower. In fact, even when their overall deficit in positive affect was takeninto account, the children with autism were found to express positive affectspecifically toward their mothers' faces only a little more than half as muchas the children with Down syndrome. Although not confirmed by statisticalanalysis, this finding is consistent with prior research (Dawson & Galpert,1990; Snow et al., 1987; Trad et al., 1993).

Relative to the children with Down syndrome, the children with autismexpressed the same amount of positive affect in relation to objects thatwere physically supported or manipulated by their mothers, but significantlyless positive affect toward objects that were not physically supported bytheir mothers. These findings suggest that affective engagement of theautistic children was more successful when their mothers actually handledand manipulated the object of shared attention, and that the autisticgroup's affective responsiveness may have been enhanced by a concretelydefined joint attention situation. This issue seems worthy of further inquiry,especially in regard to what types of interventions maximize autistic chil-dren's deficient social skills. In contrast to the findings on children's atten-tion, neither the autistic nor the Down syndrome children showed changesin the levels of positive affect they expressed in relation to the various at-tentional referents across the two visits. It is possible, however, that the


small number of visits precluded detection of developmental trends in af-fective behavior.

In summary, in a highly supportive social context conducive to optimalsocial performance, a group of high-functioning children with autismshowed deficits in both their attention and affective responsiveness to otherpeople. These findings are limited by the very small sample and the factthat several group differences, although substantial, were not confirmed bystatistical analysis. The present findings are, however, consistent with priorevidence that children with autism attend less to their partners' faces inthe context of joint attention situations (Mundy et al., 1986) and are lesslikely to use positive affective displays to communicate about objects ofmutual attention (Kasari, Sigman, et al., 1990). Further, these findings sug-gest that autistic children's deficits in eye-to-eye gaze and affective respon-sivity persist even when joint attention situations are structured and guidedby the mother in the familiar environment of the home.

An important issue to consider in evaluating the results of the presentstudy is the suitability of the Down syndrome children as a comparisongroup. There is evidence that Down syndrome children look at the facesof their social partners for longer average durations in the first (Berger &Cunningham, 1981; Landry & Chapieski, 1990) and second (Kasari, Mundy,Yirmiya, & Sigman, 1990) years of life. In addition, research on Down syn-drome children in the toddler and preschool years (Kasari, Mundy, et al.,1990; Kasari, Sigman, et al., 1990) has produced some evidence that theyexhibit higher levels of positive affect in the context of social interactionthan do normally developing children. Consequently, future research ad-dressing the core social deficits of autistic children will benefit from theinclusion of children with nonspecific mental retardation as well as normallydeveloping children.

REFERENCES

Adamson, L., & Bakeman, R. (1985). Affect and attention: Infants observed with mothersand peers. Child Development, 56, 582-593.

American Psychiatric Association. (1987). Diagnostic and statistical manual of mental disorders(3rd ed., rev.). Washington, DC: Author.

Arcus, D., Snidman, N., Campbell, P., Brandzel, S., & Zambrano, I. (1991, March). A programfor coding behavior directly from VCR to computer. Biennial Conference of the Society forResearch in Child Development, Seattle, WA.

Bakeman, R., & Adamson, I. (1984). Coordinating attention to people and objects in mother-infant and peer-infant interaction. Child Development, 55, 1278-1289.

Berger, J., & Cunningham, C. (1981). The development of eye contact between mothers andnormal versus Down's syndrome infants. Developmental Psychology, 17, 678-689.

Bloom, L., Beckwith, R., Capatides, J., & Hafitz, J. (1988). Expression through affect andwords in the transition from infancy to language. In P. Baltes, D. Featherman, & R.Lerner (Eds.), Life-span development and behavior. Hillsdale, NJ: Erlbaum.


Dawson, G., & Galpert, L. (1990). Mothers' use of imitative play for facilitating social re-sponsiveness and toy play in young autistic children. Development and Psychopathology,2, 151-162.

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

Feinman, S. (1982). Social referencing in infancy. Merrill-Palmer Quarterly, 28, 445-470.Hutt, C., & Ounsted, C. (1966). The biological significance of gaze aversion with particular

reference to the syndrome of infantile autism. Behavioral Science, 11, 346-356.Kanner, L. (1943). Autistic disturbances of affective contact. Nervous Child, 2, 217-250.Kasari, C., Mundy, P., Yirmiya, N., & Sigman, M. (1990). Affect and attention in children

with Down syndrome. American Journal on Mental Retardation, 95, 55-67.Kasari, C, Sigman, M., Mundy, P., & Yirmiya, N. (1990). Affective sharing in the context of

joint attention interactions of normal, autistic, and mentally retarded children. Journal ofAutism and Developmental Disorders, 20, 87-100.

Kasari, C, Sigman, M., & Yirmiya, N. (1993). Focused and social attention of autistic childrenin interactions with familiar and unfamiliar adults: A comparison of autistic, mentallyretarded, and normal children. Development and Psychopathology, 5, 403-414.

Knapp, M. L. (1980). Essentials of nonverbal communication. New York: Holt, Rinehart andWinston.

Landry, S., & Chapieski, M. (1990). Joint attention of six-month-old Down syndrome andpreterm infants: I, Attention to toys and mother. American Journal on Mental Retardation,94, 488-498.

Leiter, R. (1974). International Performance Scale. In O. Buros (Ed.). Tests in print II: Indexto tests, test reviews and the literature on specific tests. Highland Park, NJ: Gryphone.

Mirenda, P. L., Donnellan, A. M., & Yoder, D. E. (1983). Gaze behavior: A new look at anold problem. Journal of Autism and Developmental Disorders, 13, 397-409.

Mundy, M., Sigman, P., Ungerer, J., & Sherman, T. (1986). Defining the social deficits ofautism: The contribution of non-verbal communication measures. Journal of Child Psy-chology and Psychiatry, 27, 657-669.

Richer, J., & Coss, R. (1976). Gaze aversion in autistic and normal children. Acta PsychiatricaScandinavica, 53, 193-210.

Rutter, M. (1978). Diagnosis and definition. In M. Rutter & E. Schopler (Eds.), Autism: Areappraisal of concepts and treatment. New York: Plenum Press.

Sigman, M., Mundy, P., Sherman, T., & Ungerer, J. (1986). Social interactions of autistic,mentally retarded and normal children and their caregivers. Journal of Child Psychologyand Psychiatry, 27, 647-655.

Snow, M., Hertzig, M., & Shapiro, T. (1987). Expression of emotion in young autistic children.Journal of the American Academy of Child and Adolescent Psychiatry, 26, 836-838.

Tager-Flusberg, H., Calkins, S., Nolin, T., Baumberger, T., Anderson, M., & Chadwick-Dias,A. (1990). A longitudinal study of language acquisition in autistic and Down syndromechildren. Journal of Autism and Developmental Disorders, 20, 1-21.

Trad, P. V., Bernstein, D., Shapiro, T., & Hertzig, M. (1993). Assessing the relationship betweenaffective responsivity and social interaction in children with pervasive developmental dis-order. Journal of Autism and Developmental Disorders, 23, 361-377.

Tronick, E. (1989). Emotional communication in infants. American Psychologist, 44, 112-119.Volkmar, F., Hoder, E., & Cohen, D. (1985). Compliance, negativism, and the effects of treat-

ment structure in autism: A naturalistic, behavioral study. Journal of' Child Psychology andPsychiatry, 26, 865-877.

Volkmar, F., & Mayes, L. (1990). Gaze behavior in autism. Development and Psychopathology,2, 61-69.

Vygotsky, L. (1978). Mind in society: The development of higher psychological processes. Cam-bridge, MA: Harvard University Press.

Winer, B. (1978). Statistical principles in experimental design. New York: McGraw-Hill.Wing, L. (1976). Diagnosis, clinical description, and prognosis. In L. Wing (Ed.), Early child-

hood autism. Oxford: Pergamon.


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