Papers by Laurent Mottron
Development and Psychopathology, 2002
Recent advances in the discipline of developmental psychopathology highlight the contributions of... more Recent advances in the discipline of developmental psychopathology highlight the contributions of developmental thought to the study of persons with autism. This article briefly outlines primary developmental innovations in theory, methodology, and the interpretation of findings. Specifically, we discuss two sets of issues that arise from the general notion of developmental level. One set is relevant to the choice of persons that comprise the comparison group and the other to the various implications of the subjects' levels of functioning. In sum, we contend that researchers need to frame their empirical work within the context of developmental theory and methodology and interpret their findings accordingly. This will lead to scientifically compelling work and an increasingly heuristic approach to the study of persons with autism.
Journal of Autism and Developmental Disorders, 2006
Within the last 10 years, there has been an upsurge of interest in face processing abilities in a... more Within the last 10 years, there has been an upsurge of interest in face processing abilities in autism which has generated a proliferation of new empirical demonstrations employing a variety of measuring techniques. Observably atypical social behaviors early in the development of children with autism have led to the contention that autism is a condition where the processing of social information, particularly faces, is impaired. While several empirical sources of evidence lend support to this hypothesis, others suggest that there are conditions under which autistic individuals do not differ from typically developing persons. The present paper reviews this bulk of empirical evidence, and concludes that the versatility and abilities of face processing in persons with autism have been underestimated.

Journal of Child Psychology and Psychiatry, 2001
Memory tasks were administered to 14 high-functioning individuals with autism and 14 typically de... more Memory tasks were administered to 14 high-functioning individuals with autism and 14 typically developing individuals matched on chronological age and verbal intelligence. The tasks consisted of free and cued recall of 15 semantically unrelated words in 3 encoding conditions : phonological encoding, semantic encoding, and a no encoding orientation. In both groups, semantic orientation led to better free recall than did orientation toward syllabic encoding or absence of orientation. In contrast, semantic cues at retrieval led to better cued recall than phonological cues in typically developing individuals, whereas both types of cue had the same effect in prompting cued recall for individuals with autism. These findings are incompatible with the hypothesis of an amnesic deficit and do not support the notion of executive or semantic deficits in the memory problems of autistic individuals, at least for those with a high level of functioning. It is proposed that these findings can be accounted for by enhanced phonological processing in autism. This interpretation is consistent with other findings of enhanced processing of low-level perceptual information in the visual and auditory modality in autism.

Psychological Science, 2007
Autistics are presumed to be characterized by cognitive impairment, and their cognitive strengths... more Autistics are presumed to be characterized by cognitive impairment, and their cognitive strengths (e.g., in Block Design performance) are frequently interpreted as low-level by-products of high-level deficits, not as direct manifestations of intelligence. Recent attempts to identify the neuroanatomical and neurofunctional signature of autism have been positioned on this universal, but untested, assumption. We therefore assessed a broad sample of 38 autistic children on the preeminent test of fluid intelligence, Raven's Progressive Matrices. Their scores were, on average, 30 percentile points, and in some cases more than 70 percentile points, higher than their scores on the Wechsler scales of intelligence. Typically developing control children showed no such discrepancy, and a similar contrast was observed when a sample of autistic adults was compared with a sample of nonautistic adults. We conclude that intelligence has been underestimated in autistics.
American Journal of Medical Genetics Part B-neuropsychiatric Genetics, 2005
Jamain [2003: Nat Genet 34:27–29] recently reported mutations in two neuroligin genes in sib-pair... more Jamain [2003: Nat Genet 34:27–29] recently reported mutations in two neuroligin genes in sib-pairs affected with autism. In order to confirm these causative mutations in our autistic population and to determine their frequency we screened 96 individuals affected with autism. We found no mutations in these X-linked genes. These results indicate that mutations in NLGN3 and NLGN4 genes are responsible for at most a small fraction of autism cases and additional screenings in other autistic populations are needed to better determine the frequency with which mutations in NLGN3 and NLGN4 occur in autism. © 2004 Wiley-Liss, Inc.
Journal of Child Psychology and Psychiatry, 2003

Neuropsychologia, 2004
This series of experiments was aimed at assessing spatial abilities in high functioning individua... more This series of experiments was aimed at assessing spatial abilities in high functioning individuals with autism (HFA), using a human-size labyrinth. In the context of recent findings that the performance of individuals with HFA was superior to typically developing individuals in several non-social cognitive operations, it was expected that the HFA group would outperform a typically developing comparison group matched on full-scale IQ. Results showed that individuals with autism performed all spatial tasks at a level at least equivalent to the typically developing comparison group. No differences between groups were found in route and survey tasks. Superior performance for individuals with HFA was found in tasks involving maps, in the form of superior accuracy in graphic cued recall of a path, and shorter learning times in a map learning task. We propose that a superior ability to detect [Human Perception and Performance 27 719], match [Journal of Child Psychology and Psychiatry 34 (1993) 1351] and reproduce [Journal of Child Psychology and Psychiatry 40 743] simple visual elements yields superior performance in tasks relying on the detection and graphic reproduction of the visual elements composing a map. Enhanced discrimination, detection, and memory for visually simple patterns in autism may account for the superior performance of persons with autism on visuo-spatial tasks that heavily involve pattern recognition, either in the form of recognizing and memorizing landmarks or in detecting the similarity between map and landscape features. At a neuro-anatomical level, these findings suggest an intact dorso-lateral pathway, and enhanced performance in non social tasks relying on the infero-temporal pathway.

Journal of Child Psychology and Psychiatry, 1999
In the present study, copying tasks were used to assess hierarchical aspects of visual perception... more In the present study, copying tasks were used to assess hierarchical aspects of visual perception in a group of 10 nonsavant autistic individuals with normal intelligence. In Experiment 1, the hierarchical order of graphic construction and the constancy of this order were measured for the copying of objects and nonobjects. In comparison to control participants, autistic individuals produced more local features at the start of the copying. However, they did not differ from controls with respect to graphic constancy. Experiment 2 measured the effect of geometrical impossibility on the copying of figures. Results revealed that autistic individuals were less affected by figure impossibility than were controls. Therefore, these experiments seem to support the notion of a local bias for visual information processing in individuals with autism. Two interpretations are proposed to account for this effect. According to the hierarchical deficit hypothesis, individuals with autism do not manifest the normal global bias in perceiving scenes and objects. Alternatively, the executive function hypothesis suggests that autism brings about limitations in the complexity of information that can be manipulated in short-term visual memory during graphic planning.
Neuroreport, 2000
Acknowledgements: This study was supported in part by the Fonds de la recherche en Sante  du Que... more Acknowledgements: This study was supported in part by the Fonds de la recherche en Sante  du Que Âbec.

Neuropsychology, 2006
Configural processing in autism was studied in Experiment 1 by using the face inversion effect. A... more Configural processing in autism was studied in Experiment 1 by using the face inversion effect. A normal inversion effect was observed in the participants with autism, suggesting intact configural face processing. A priming paradigm using partial or complete faces served in Experiment 2 to assess both local and configural face processing. Overall, normal priming effects were found in participants with autism, irrespective of whether the partial face primes were intuitive face parts (i.e., eyes, nose, etc.) or arbitrary segments. An exception, however, was that participants with autism showed magnified priming with single face parts relative to typically developing control participants. The present findings argue for intact configural processing in autism along with an enhanced processing for individual face parts. The face-processing peculiarities known to characterize autism are discussed on the basis of these results and past congruent results with nonsocial stimuli.

Brain, 2006
In order to explain the cognitive and cerebral mechanisms responsible for the visuospatial peak i... more In order to explain the cognitive and cerebral mechanisms responsible for the visuospatial peak in autism, and to document its specificity to this condition, a group of eight high-functioning individuals with autism and a visuospatial peak (HFA-P) performed a modified block-design task (BDT; subtest from Wechsler scales) at various levels of perceptual cohesiveness, as well as tasks tapping visuomotor speed, global perception, visual memory, visual search and speed of visual encoding. Their performance was compared with that of 8 autistics without a visuospatial peak (HFA-NP), 10 typically developing individuals (TD) and 8 gifted comparison participants with a visuospatial peak (TD-P). Both HFA-P and HFA-NP groups presented with diminished detrimental influence of increasing perceptual coherence compared with their BDT-matched comparison groups. Neither autistic group displayed a deficit in construction of global representations. The HFA-P group showed no differences in performance level or profile in comparison with the gifted BDT-matched [i.e. higher full-scale IQ (FSIQ)] group, apart from locally oriented perception. Diminished detrimental influence of perceptual coherence on BDT performance is both sensitive and specific to autism, and superior low-level processing interacts with locally oriented bias to produce outstanding BDT performance in a subgroup of autistic individuals. Locally oriented processing, enhanced performance in multiple tasks relying on detection of simple visual material and enhanced discrimination of first-order gratings converge towards an enhanced functioning and role of the primary visual cortex (V1) in autism. In contrast, superior or typical performance of autistics in tasks requiring global processing is inconsistent with the global-deficit-driven Weak Central Coherence hypothesis and its neurobiological magnocellular deficit counterpart.
Journal of Cognitive Neuroscience, 2003
& Past research has shown a superiority of participants with high-functioning autism over compari... more & Past research has shown a superiority of participants with high-functioning autism over comparison groups in memorizing picture -pitch associations and in detecting pitch changes in melodies. A subset of individuals with autism,
Journal of Child Psychology and Psychiatry, 2000

Journal of Autism and Developmental Disorders, 2006
We propose an ''Enhanced Perceptual Functioning'' model encompassing the main differences between... more We propose an ''Enhanced Perceptual Functioning'' model encompassing the main differences between autistic and non-autistic social and non-social perceptual processing: locally oriented visual and auditory perception, enhanced low-level discrimination, use of a more posterior network in ''complex'' visual tasks, enhanced perception of first order static stimuli, diminished perception of complex movement, autonomy of low-level information processing toward higher-order operations, and differential relation between perception and general intelligence. Increased perceptual expertise may be implicated in the choice of special ability in savant autistics, and in the variability of apparent presentations within PDD (autism with and without typical speech, Asperger syndrome) in non-savant autistics. The overfunctioning of brain regions typically involved in primary perceptual functions may explain the autistic perceptual endophenotype.

Brain, 2005
A growing body of evidence indicates that people with autism frequently experience sleep disorder... more A growing body of evidence indicates that people with autism frequently experience sleep disorders and exhibit atypical sleep architecture. In order to establish whether sleep disorders truly belong to the autism spectrum disorder (ASD) phenotype, we conducted a subjective and objective study of sleep in a group of high-functioning adults with ASD but without sleep complaints, psychiatric disorders or neurological comorbidity. We compared the subjective data of 27 ASD participants with those of 78 healthy controls matched for chronological age and gender. Subjective measures of sleep in the clinical group were compatible with insomnia and/or a tolerable phase advance of the sleep-wake cycle. Subjective data were confirmed by objective laboratory sleep recordings in a subset of 16 patients and 16 controls. Persons with autism presented with a longer sleep latency (P < 0.04), more frequent nocturnal awakenings (P < 0.03), lower sleep efficiency (P < 0.03), increased duration of stage 1 sleep (P < 0.02), decreased non-REM sleep (stages 2 + 3 + 4, P < 0.04) and slow-wave sleep (stages 3 + 4, P < 0.05), fewer stage 2 EEG sleep spindles (P < 0.004), and a lower number of rapid eye movements during REM sleep (P < 0.006) than did control participants. On clinical scales, the scores of persons with ASD on the Beck Depression Inventory were similar to those of persons without, but their trait anxiety scores on the Spielberger Anxiety Scale were higher (P < 0.02). The state anxiety scores of the Spielberger scale and cortisol levels were the same in the two groups. Objective total sleep time correlated negatively with the Social (À0.52, P < 0.05) and Communication (À0.54, P < 0.02) scales of the Autism Diagnostic Interview-Revised. The sleep of clinical subgroups (10 with high-functioning autism, six with Asperger syndrome) did not differ, except for the presence of fewer EEG sleep spindles in the Asperger syndrome subgroup (P < 0.05).

Autism, 2003
The study examined developmental changes in autistic symptoms retrospectively in a sample of 28 v... more The study examined developmental changes in autistic symptoms retrospectively in a sample of 28 verbal children and adolescents with autism. Individuals with Asperger syndrome, PDD-NOS, and related medical conditions were not included in the study. We compared autistic symptoms present at the retrospective assessment and during the 4-to 5-year age period using the ADI-R. Our findings revealed a significant improvement in the three domains relevant for the diagnosis of autism, independent of age or IQ level. Improvement occurred in more symptoms from the social than the communication domain, and for more symptoms from the latter than the restricted interest and repetitive behavior domains. Finally, several ADI-R symptoms decreased in prevalence or even improved with development, suggesting they are developmentally specific. The finding that improvement was not linked to level of functioning and was found in individuals still positive for a diagnosis of autism suggests that improvement belongs to the 'natural history' of the handicap

Journal of Child Psychology and Psychiatry, 1999
Two tasks were used to assess the processing of whole versus parts of objects in a group of high-... more Two tasks were used to assess the processing of whole versus parts of objects in a group of high-functioning children and adolescents with autism (N l 11) and a comparison group of typically developing peers (N l 11) matched for chronological age and IQ. In the first task, only the children with autism showed a global advantage, and the two groups showed similar interference between levels. In the second task, the children with autism, despite longer RTs, showed similar performance to the comparison group with regard to the effect of goodness on visual parsing. Contrary to expectations based on the central coherence and hierarchisation deficit theories, these findings indicate intact holistic processing among persons with autism. The implications of these findings are discussed in relation to apparently discrepant evidence from other studies.
Cognitive Brain Research, 2005
Current research indicates that human gaze direction is a special cue for shifting attention for ... more Current research indicates that human gaze direction is a special cue for shifting attention for one of two reasons: (1) it reflects social desires and intentions and (2) its basic perceptual features usually correspond to important events in the environment. This study, conducted with individuals with autism and with age-and IQ-matched typically developing individuals, dissociates these two often-confounded explanations and demonstrates that eyes appear to be special for typically developing individuals because of their social power, whereas gaze effects are mediated by feature correspondence among persons with autism. D 2005 Elsevier B.V. All rights reserved.
Development and Psychopathology, 2002
Recent advances in the discipline of developmental psychopathology highlight the contributions of... more Recent advances in the discipline of developmental psychopathology highlight the contributions of developmental thought to the study of persons with autism. This article briefly outlines primary developmental innovations in theory, methodology, and the interpretation of findings. Specifically, we discuss two sets of issues that arise from the general notion of developmental level. One set is relevant to the choice of persons that comprise the comparison group and the other to the various implications of the subjects' levels of functioning. In sum, we contend that researchers need to frame their empirical work within the context of developmental theory and methodology and interpret their findings accordingly. This will lead to scientifically compelling work and an increasingly heuristic approach to the study of persons with autism.
Journal of Autism and Developmental Disorders, 2006
Within the last 10 years, there has been an upsurge of interest in face processing abilities in a... more Within the last 10 years, there has been an upsurge of interest in face processing abilities in autism which has generated a proliferation of new empirical demonstrations employing a variety of measuring techniques. Observably atypical social behaviors early in the development of children with autism have led to the contention that autism is a condition where the processing of social information, particularly faces, is impaired. While several empirical sources of evidence lend support to this hypothesis, others suggest that there are conditions under which autistic individuals do not differ from typically developing persons. The present paper reviews this bulk of empirical evidence, and concludes that the versatility and abilities of face processing in persons with autism have been underestimated.
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Papers by Laurent Mottron