Autism and related conditions.
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Adrenal Cortex Hormones↗
Biomedical subjects
C Lord
Publications and source records attributed to C Lord.
Language level and nonverbal social-communicative behaviors in autistic and language-delayed children.
OBJECTIVE: To explore the relationship of general expressive language delay to nonverbal social-communicative deficits and repetitive behaviors associated with autism in preschool children. METHOD: Interviews of the parents of 51 autistic and 43 nonautistic 3- to 5-year-olds with language impairments were compared. RESULTS: Main effects of the children's language level occurred for the majority of social and nonverbal communication items but not for restricted, repetitive behaviors or showing and directing attention, socially directed gaze, or range of facial expression. CONCLUSIONS: In addition to the specific impairments of autism, a broader conceptualization of communication handicap is urged for preschool children with developmental delays.
Attention↗
The pre-linguistic autism diagnostic observation schedule.
The Pre-Linguistic Autism Diagnostic Observation Schedule (PL-ADOS) is a semistructured observation scale designed for use as a diagnostic tool for children less than 6 years old who are not yet using phrase speech and are suspected of having autism. The PL-ADOS takes approximately 30 minutes to administer and is appropriate for use with this population because of its emphasis on playful interactions and the use of toys designed for young children. Reliability studies indicated that both individual activity ratings and summary ratings could be reliably scored from videotaped assessments by naive raters. Additionally, PL-ADOS scores of nonverbal preschool-aged children referred for clinical diagnosis and classified on the basis of a diagnostic team's clinical judgment, clearly discriminated between autistic and nonautistic developmentally disabled children. The resulting diagnostic algorithm is theoretically linked to diagnostic constructs associated with ICD-10 and DSM-IV criteria for autism.
Autistic Disorder↗
Follow-up of two-year-olds referred for possible autism.
Thirty, 2-year-old children referred for possible autism were evaluated using a parent interview, a rating scale and psychometric tests and reassessed one year later. Clinical diagnosis was relatively stable across time; diagnosis using the formal measures changed significantly, particularly for younger and more developmentally delayed children. Several patterns contributed to the increasing differentiation of children with autism from age 2 to 3, including the development of clearly recognizable, repetitive behaviors in the autistic children and significant improvements in basic social skills in the children judged not to be autistic.
Autistic Disorder↗
Autism Diagnostic Interview-Revised: a revised version of a diagnostic interview for caregivers of individuals with possible pervasive developmental disorders.
Describes the Autism Diagnostic Interview-Revised (ADI-R), a revision of the Autism Diagnostic Interview, a semistructured, investigator-based interview for caregivers of children and adults for whom autism or pervasive developmental disorders is a possible diagnosis. The revised interview has been reorganized, shortened, modified to be appropriate for children with mental ages from about 18 months into adulthood and linked to ICD-10 and DSM-IV criteria. Psychometric data are presented for a sample of preschool children.
Algorithms↗
Field trial for autistic disorder in DSM-IV.
OBJECTIVE: This project focused on the development of the definition of autism for DSM-IV. METHOD: Multiple sites were involved in obtaining information regarding 977 patients with the following clinician-assigned diagnoses: autism (N = 454), other pervasive developmental disorders (N = 240), and other disorders (N = 283). A standard coding system was used, and the raters (N = 125) had a range of experience in the diagnosis of autism. Patterns of agreement among existing diagnostic systems were examined, as was the rationale for inclusion of other disorders within the class of pervasive developmental disorders. RESULTS: The DSM-III-R definition of autism was found to be overly broad. The proposed ICD-10 definition most closely approximated the clinicians' diagnoses. Inclusion of other disorders within pervasive developmental disorders appeared justified. Partly on the basis of these data, modifications in the ICD-10 definition were made; this and the DSM-IV definition are conceptually identical. CONCLUSIONS: The resulting convergence of the DSM-IV and ICD-10 systems should facilitate both research and clinical service.
Age of Onset↗
Sex differences in higher functioning people with autism.
Though a sex difference in the incidence of autism has frequently been reported, few studies have considered sex differences in the severity of features associated with autism. The Autism Diagnostic Interview was used to assess the difference between a group of 21 females and 21 males with autism with equivalent chronological nonverbal IQ greater than 60. Males were rated to be more severely autistic than females on several measures of early social development, but not in any other areas. Results are discussed in relationship to hypotheses based on sex differences in other populations.
Activities of Daily Living↗
Birth order effects on nonverbal IQ in families with multiple incidence of autism or pervasive developmental disorder.
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Adolescent↗
A follow-up study of high-functioning autistic children.
Fifty-eight high-functioning autistic children were assessed during preschool and early school years and followed over a period of 8 years. Early and current psychometric and language tests, parent interviews concerning autistic symptomatology, and direct observations were examined as predictors of the Vineland Adaptive Behavior Scales and scores on standardized achievement tests. Verbal skills emerged as the strongest predictor of social-adaptive functioning. Clear, positive relationships also emerged between intellectual functioning, and academic attainment. Early non-verbal IQ also showed a positive relationship with outcome. Academic performance appeared considerably stronger than in earlier studies.
Achievement↗
Production of polyclonal antibody to the bovine adrenal atrial natriuretic factor-R1 receptor.
A polyclonal antibody monospecific for an intracellular epitope of the atrial natriuretic factor (ANF)-R1 receptor was produced. The receptor protein (200 pmoles) was purified to homogeneity from bovine adrenal zona glomerulosa (BAZG), reduced, alkylated and digested with trypsin. The tryptic fragments were purified by reverse-phase h.p.l.c. on a C18 column. Based on the sequence of one of these fragments, a peptide was chemically synthesized, coupled to thyroglobulin and injected into rabbits. The antibody obtained was shown to be specific for the R1-type as no receptor was detected in bovine red blood cells (RBC) (which are devoid of ANF receptors) and in NIH-3T3 cell membranes (where only the R2-type is expressed). Several other tissues were screened and comparison of the immunoreactive receptor density estimates with those obtained by ANF binding yielded a correlation coefficient (r2) of 0.965. The minimal detectable dose was typically 3 fmoles/tube and the ED50 of the RIA was 30 fmoles/tube. Cyanogen bromide digestion of the receptor was essential for antigenic detection, indicating that the epitope is probably hindered due to the tertiary structure of the native protein. Moreover, location of the epitope in the kinase homology domain of the receptor, combined with partial tryptic digestion, suggests that the proteolysis-sensitive region of the receptor is located between the transmembrane-spanning domain and the amino acid 586. This method of production of antibodies should be useful to precisely map the amino acids involved in various functions of the receptor.
Adrenal Glands↗
Neologisms and idiosyncratic language in autistic speakers.
Language samples from matched groups of 80 autistic, mentally handicapped, and normally developing children were coded for the presence of neologisms and/or idiosyncratic language use. Cognitive, social, or linguistic factors that might account for these errors were identified and assessed. More autistic subjects used neologisms and idiosyncratic language than age- and language skill-matched control groups. No single factor or combination of factors was responsible for this difference. Across diagnostic groups, similar patterns of error were noted, except that the autistic subjects were more likely to use words inappropriately that had no phonological or semantic similarity to the intended English word. For the autistic groups, the frequency of idiosyncratic language increased with language complexity. In contrast, such errors decreased with language skill in the mentally handicapped group. Theoretical implications for determining the nature and source of the language disorder associated with autism are discussed.
Adolescent↗
Pre- and perinatal factors in high-functioning females and males with autism.
Pregnancy and delivery complications as indicated in medical records and maternal reports for 23 high-functioning autistic females and 23 high-functioning males of similar IQ and age were compared with those of 54 of their normally developing siblings. Autistic subjects of both sexes had higher non-optimality scores than their siblings. Much of this difference was accounted for by a higher incidence of firstborns and fourth- or later-borns in the autistic group. Of factors found in previous research with mentally handicapped, autistic samples, only estimated weeks of gestation greater than 42 occurred more often in autistic subjects than siblings. The only sex difference specific to the autistic group was that autistic males came from larger families than females. These data provide slight support for the contribution of nonspecific pre- and perinatal factors to other etiological bases of autism. It is proposed that pre- and perinatal factors may play less of a role in autism in high-functioning individuals than suggested in studies of autism associated with severe retardation.
Adolescent↗
Methods and measures of behavior in the diagnosis of autism and related disorders.
In the past 5 years, diagnostic schemes for autism and related psychiatric disorders have become increasingly sophisticated. However, within these diagnostic frameworks, no specific assessment procedures have been prescribed. On the other hand, work has continued in the development of empirically rooted instruments for the diagnosis and screening of autism and related disorders. The need for diagnostic methods and instruments that incorporate current diagnostic criteria, that use methods specifically aimed at gleaning information about the communicative and social deficits associated with autism, and that differentiate autism from related disorders is discussed. Two new instruments that attempt to fill this need, the Autism Diagnostic Interview and the Autism Diagnostic Observation Schedule, are briefly described.
Autistic Disorder↗
Topographical characterization of the domain structure of the bovine adrenal atrial natriuretic factor R1 receptor.
We have studied the structure and function of the membrane atrial natriuretic factor R1 (ANF-R1) receptor using limited proteolysis and exoglycosidase treatment. Limited digestion with trypsin of the receptor from bovine adrenal zona glomerulosa membranes resulted in the conversion of the native 130-kDa receptor into a single membrane-associated ANF-binding proteolytic fragment of 70 kDa. The 70-kDa fragment bound ANF with enhanced binding affinity but retained intact ANF-R1 pharmacological specificity and was still sensitive to modulation by amiloride. Trypsin treatment of the membranes produced a dual effect on ANF binding. Low concentrations of trypsin (less than or equal to 25 micrograms/mg of protein) increased ANF binding while higher concentrations dose dependently reduced the binding of the hormone. The increase of ANF-binding activity was associated with the formation of the 70-kDa fragment while the loss of ANF binding paralleled the degradation of the 70-kDa fragment. Low concentrations of trypsin drastically decreased the ANF-sensitive guanylate cyclase activity of the membrane fraction. This loss of catalytic activity strongly correlated with the formation of the 70-kDa tryptic fragment. We also evaluated the effect of ANF binding on the susceptibility of the receptor to proteolytic cleavage. The occupied receptor exhibited a greater sensitivity to trypsin digestion than the unoccupied protein, consistent with the hypothesis that hormone binding induces an important conformational change in the receptor structure. On the other hand, the 70-kDa fragment was much more resistant to proteolysis when occupied by ANF, suggesting that the ANF-binding domain forms a very compact structure.(ABSTRACT TRUNCATED AT 250 WORDS)
Amiloride↗
Autism diagnostic observation schedule: a standardized observation of communicative and social behavior.
The Autism Diagnostic Observation Schedule (ADOS), a standardized protocol for observation of social and communicative behavior associated with autism, is described. The instrument consists of a series of structured and semistructured presses for interaction, accompanied by coding of specific target behaviors associated with particular tasks and by general ratings of the quality of behaviors. Interrater reliability for five raters exceeded weighted kappas of .55 for each item and each pair of raters for matched samples of 15 to 40 autistic and nonautistic, mildly mentally handicapped children (M IQ = 59) between the ages of 6 and 18 years. Test-retest reliability was adequate. Further analyses compared these groups to two additional samples of autistic and nonautistic subjects with normal intelligence (M IQ = 95), matched for sex and chronological age. Analyses yielded clear diagnostic differences in general ratings of social behavior, specific aspects of communication, and restricted or stereotypic behaviors and interests. Clinical guidelines for the diagnosis of autism in the draft version of ICD-10 were operationalized in terms of abnormalities on specific ADOS items. An algorithm based on these items was shown to have high reliability and discriminant validity.
Adolescent↗
The role of age at assessment, developmental level, and test in the stability of intelligence scores in young autistic children.
Longitudinal comparisons were made of intelligence and developmental quotient (IQ/DQ) scores for three age groups of 70-72 autistic children aged 2 to 3, 4 to 5, and 6 to 7 years at initial assessment and reassessed at least 2 years later. Stability and predictability over a mean follow-up period of 5 years were related to age, developmental level, and test used at initial assessment. IQ/DQs during preschool years were quite stable and predictive of later IQ scores, except when early scores on the Bayley Scales of Mental Development were compared with later scores on performance or nonverbal tests. As for other populations, predictability for young autistic children was strongest when the same test was used at both assessments, and when children were 4 years or older at initial assessment.
Age Factors↗
Autism diagnostic interview: a standardized investigator-based instrument.
The development of a new standardized investigator-based interview for use in the differential diagnosis of pervasive developmental disorders is described, together with a diagnostic algorithm (using ICD-10 criteria) based on its use. Good interrater reliability for algorithm items was shown between four raters, two in Canada and two in the UK, who rated 32 videotaped interviews. The items also significantly discriminated between 16 autistic and 16 nonautistic mentally handicapped subjects. The algorithm based on ICD-10 identified all 16 autistic individuals and none of the 16 nonautistic subjects.
Adolescent↗
Stability of assessment results of autistic and non-autistic language-impaired children from preschool years to early school age.
The predictability, consistency in group means, and intra-individual stability of developmental quotients and performance IQs were assessed from preschool to school age for 71 autistic children and 71 non-autistic communication-handicapped children, matched on chronological age, sex and initial performance IQ/DQ. DQs/performance IQs at age 4 yrs were found to be highly correlated with performance IQ at age 10 yrs for both groups. Absolute difference scores and group means were also equivalent for both samples, with no difference in patterns of change or the relationship between performance IQ and language status, as measured on the PPVT. Differences between diagnostic groups occurred only for scores on the Vineland Social Maturity Scale and the relationship between these scores and IQ.
Autistic Disorder↗