Platelet serotonin (5HT) levels of 5 autistic subjects (ages 16-37) who had siblings with either autism or pervasive developmental disorder were significantly higher than levels of 23 autistic subjects without affected siblings. Autistic subjects without affected siblings had 5HT levels significantly higher than 10 normal controls. Sex, age, and…

Diagnoses for autism based on the Autism Diagnostic Interview-Revised (ADI-R) and the Childhood Autism Rating Scale (CARS) were examined for 83 individuals with suspected autism. Individuals diagnosed with autism based on only one system were significantly younger than those with diagnoses based on both systems. Comparison for possible gender…

Comparison of 384 male and 91 female autistic children (three through eight years old) revealed that females as a group scored less well on intelligence tests. Boys also performed better than girls on eye-hand integration and perceptual tasks. Predictions of female superiority in affect and receptive vocabulary were not supported. (CL)

This study examined behavioral adjustment in 22 siblings of children with autism. Mothers rated these children as having more behavior problems and fewer prosocial behaviors than a normative sample. Analysis of variables revealed that male siblings and children younger than the autistic sibling engaged in fewer prosocial behaviors. Psychological…

Interviews with 21 high-functioning adults with autism and 20 mildly to moderately mentally retarded adults without autism indicated that the mentally retarded group had more sexual experiences, with no intergroup differences in sexual knowledge or interest. Intelligence quotient was positively correlated with knowledge scores and males had…

The study sought to determine whether 100 emotionally disturbed, mentally retarded Ss assigned four distinct diagnostic labels could be differentiated from each other on the basis of sex, age, degree of mental impairment, and adaptive behavior. (Author)

A Canadian study compared the rate of cognitive disabilities in 156 relatives of 49 individuals with autism to that found in 55 relatives of 18 individuals with mental retardation. No differences were found; however, female and low IQ individuals were found to have higher family histories of cognitive disabilities. (Author/CR)

This study investigated associations between selected infant and maternal characteristics and autism risk in 4381 California children with autism. Increased risk factors were observed for males, multiple births, and children born to black mothers. Risk increased as maternal age and maternal education increased. Children of immigrant mothers had…

Results from analyses of sex ratios as a function of IQ are presented for 623 autistic children and 506 nonautistic communication-handicapped and behavior-disordered children. Proportionately more autistic females were found to have IQs of 34 or below than above 34. However, a linear trend of an increasing number of males with increasing…

This study of 199 individuals with autism, 74 with pervasive developmental disorder or autistic-like symptoms (PDD-NOS), and 215 with non-PDD developmental disorders found that the 3 groups differed in the various measures of severity of autism. Sex differences were primarily confined to intelligence quotient and were not prominent in other…

Teacher ratings on the Aberrant Behavior Checklist were collected on 666 students with mental retardation attending special classes. Classroom placement and age had significant effects on subscale scores, whereas sex failed to affect ratings. The study concludes that the original scoring method, developed for individuals in residential facilities,…

A study examined 233 children's ratings of attitudes and behavioral interventions toward a peer with or without autism. Both third- and sixth-grade children showed less positive attitudes toward children with autism. Children showed no differences on behavioral intentions. Information about autism did not affect ratings. (Contains references.)…

The results showed that the performance of the autistic children was better than the other two groups on concrete discrimination tasks, was poorer than the other two groups on formal discrimination tasks, and the quality of the autistic children's performance decreased as task requirements for formal discrimination increased. (Author/SB)

A literature review of autism and tuberous sclerosis complex (TSC) substantiates a significant association between the two. Studies of 14 autistic probands and 13 TSC probands identified 7 TSC subjects with autism, who had more seizures and mental retardation than those without autism. More male TSC probands with autism than female were…

This study of hyperlexia in 80 children with developmental delays found no significant differences in the frequency of hyperlexia in girls compared with boys; a significantly elevated frequency of hyperlexia in children diagnosed with pervasive developmental disorders (PDD) compared with children with non-PDD diagnoses; and a similar range of IQ…