Learn More
OBJECTIVE The objective of this study was to determine whether the phenotypic variation in autism and the related pervasive developmental disorders (PDDs) is a unitary construct or whether it is composed of distinct dimensions of autistic symptoms and measures of level of functioning. METHOD One hundred twenty-nine children with autism and other forms of(More)
BACKGROUND Brain function, as indexed by brain electrical activity, is heritable in humans, and it may be impaired in autism. Autism also has strong genetic determinants, and like all major psychiatric disorders, its complex clinical phenotype renders genetic studies difficult. Innovative strategies focused on alternative biological phenotypes are needed.(More)
Studies on hyperactivity have shown the importance of distinguishing hyperactive children according to the pervasiveness of their symptoms. To verify the meaningfulness of this distinction in Attention Deficit Disorders, an epidemiological study was undertaken. Sixteen pervasive-ADD, nine situational-ADD and 28 non-ADD children selected from a general(More)
Previous studies of the neurobiology of autism that have used the brainstem auditory evoked response have given contradictory results. The authors of this study considered two supplementary aspects; they added an ipsilateral masking procedure, and they compared the results for every subject to the values (corrected for age and sex) of a large number of(More)
We report on an epidemiological-clinical study of the New York (NY) Longitudinal Study temperament model in a consecutive sample of children (N = 814) referred to a child psychiatric center. Temperament comparisons in this clinical population were made by using temperament normative values obtained in previous random samples of the general population in the(More)
Two temperamentally extreme (extremely easy and extremely difficult) subgroups of children were selected at the age of 7 years from a large random sample of the general population of Quebec City. The clinical status, family functioning, IQ, and academic performance of these children were reassessed at 12 and 16 years of age. Findings suggest that extreme(More)
The authors assessed the predictive value of "difficult" temperament, as defined in the New York Longitudinal Study, in 12-year-old children from the general population of Quebec City whose temperaments had been determined to be difficult or easy at age 7. The difficult and easy temperament groups were balanced for age, sex, and socioeconomic status. The(More)
Normative values of brain-stem auditory evoked response (BAER) derived from a large (N = 174) normal school age sample are presented. In our 4-14 years of age sample we found a significant influence of sex on some BAER components, and a significant influence of age on others. The norms have been computed according to these influences. Particular aspects of(More)
The influences of age and sex on the BAER latency values are analysed in a non-clinical sample of adults and children. We found (1) that BAER values vary according to age and sex, but for the III-V interpeak latency (IPL); (2) that the age effect is more important than the sex effect on absolute latency (AL) II, III and V; (3) that there is a significant(More)
Few, if any, of children's behavioural or cognitive characteristics assessed in the first years of life demonstrate stability until later childhood; early characteristics have so far failed to show an association with future psychopathology. This longitudinal study, from 4-8 months to 4.7 years old, focused on stability and change of extreme temperamental(More)