Évaluation de l'intelligence des enfants autistes à l'âge préscolaire et scolaire

Autistic intelligence has fascinated scientists since the first descriptions of autism. The peaks of ability shown by some autistic people are indeed impressive and somewhat mysterious. Research has showed that these peaks are characteristic of the autistic cognitive profile. Indeed, a heterogeneous profile within subscales of intelligence tests and an uneven performance across different intelligence tests were found and replicated by many researchers. Autistic intelligence seems to rely on different cognitive processes in which perception seems to play an increased role. It is however unclear whether this knowledge regarding autistic intellectual profile, including the reasoning processes is true for the entire Autism Spectrum. Most of the research focussed on school-age (or older) autistic children and on the more «able» individuals of the spectrum. The first part of the thesis therefore focussed on assessing intelligence in so-called «low functioning» school-age autistic children. The sample for this first study was composed of minimally verbal individuals considered as «untestable» via conventional assessment. They underwent a strength-informed assessment which included both cognitive and perceptual tests. The majority of the sample (65%) obtained scores within the normal intelligence range on a nonverbal intelligence test, thus confirming that differences between intelligence tests also characterize this part of the autism spectrum. Additionally, only in the autistic group were correlations found between the perception tasks and the non-verbal intelligence tests, highlighting the role of perception in autistic intelligence. The second part of the thesis focussed on assessing intelligence in preschool-aged autistic children of all levels of functioning. Results first showed that testability is an important issue when assessing children of that age-range, especially autistic children. Indeed, testability was found to positively correlate with age in both autistic and non-autistic groups, and to be significantly lower in the autistic group. Testability was not related to performance on the cognitive tests. Significant differences between intelligence tests, and links between perception and intelligence, were also found in this sample. iv The third part of the thesis focussed on the exploration of potential indicators of intelligence in preschool-aged autistic children. The potential indicators targeted were the restricted interests and repetitive behaviours that are part of the autism diagnostic. No link was found between any of the cognitive tests and the interests or behaviours displayed by the children. In sum, intelligence assessment of autistic children bears important challenges, especially with younger children, and must be done with caution. The differences between intelligence tests and the particular role of perception in autism cognition seem to characterize the whole Autism Spectrum. Exploration of potential intelligence indicators, which can be observed without a formal assessment and early in the child's development, is worth investigating given the difficulties related to the assessment of autistic children and the role of this assessment in following interventions.

Keyphrases: Autism, Intelligence, Assessment, Cognition, Perception