Olfactory stem cells reveal MOCOS as a new player in autism spectrum disorders.

With an onset under the age of 3 years, autism spectrum disorders (ASDs) are now understood as diseases arising from pre- and/or early postnatal brain developmental anomalies and/or early brain insults. To unveil the molecular mechanisms taking place during the misshaping of the developing brain, we chose to study cells that are representative of the very early stages of ontogenesis, namely stem cells. Here we report on MOlybdenum COfactor Sulfurase (MOCOS), an enzyme involved in purine metabolism, as a newly identified player in ASD. We found in adult nasal olfactory stem cells of 11 adults with ASD that MOCOS is downregulated in most of them when compared with 11 age- and gender-matched control adults without any neuropsychiatric disorders. Genetic approaches using in vivo and in vitro engineered models converge to indicate that altered expression of MOCOS results in neurotransmission and synaptic defects. Furthermore, we found that MOCOS misexpression induces increased oxidative-stress sensitivity. Our results demonstrate that altered MOCOS expression is likely to have an impact on neurodevelopment and neurotransmission, and may explain comorbid conditions, including gastrointestinal disorders. We anticipate our discovery to be a fresh starting point for the study on the roles of MOCOS in brain development and its functional implications in ASD clinical symptoms. Moreover, our study suggests the possible development of new diagnostic tests based on MOCOS expression, and paves the way for drug screening targeting MOCOS and/or the purine metabolism to ultimately develop novel treatments in ASD.

[Slowing down the flow of facial information enhances facial scanning in children with autism spectrum disorders: A pilot eye tracking study]. / Amélioration de l'exploration visuelle d'un visage par des enfants avec autisme grâce au ralentissement de la dynamique faciale : une étude préliminaire en oculométrie.

OBJECTIVE: Face and gaze avoidance are among the most characteristic and salient symptoms of autism spectrum disorders (ASD). Studies using eye tracking highlighted early and lifelong ASD-specific abnormalities in attention to face such as decreased attention to internal facial features. These specificities could be partly explained by disorders in the perception and integration of rapid and complex information such as that conveyed by facial movements and more broadly by biological and physical environment. Therefore, we wish to test whether slowing down facial dynamics may improve the way children with ASD attend to a face. METHODS: We used an eye tracking method to examine gaze patterns of children with ASD aged 3 to 8 (n=23) and TD controls (n=29) while viewing the face of a speaker telling a story. The story was divided into 6 sequences that were randomly displayed at 3 different speeds, i.e. a real-time speed (RT), a slow speed (S70=70% of RT speed), a very slow speed (S50=50% of RT speed). S70 and S50 were displayed thanks to software called Logiral™, aimed at slowing down visual and auditory stimuli simultaneously and without tone distortion. The visual scene was divided into four regions of interest (ROI): eyes region; mouth region; whole face region; outside the face region. The total time, number and mean duration of visual fixations on the whole visual scene and the four ROI were measured between and within the two groups. RESULTS: Compared to TD children, children with ASD spent significantly less time attending to the visual scenes and, when they looked at the scene, they spent less time scanning the speaker's face in general and her mouth in particular, and more time looking outside facial area. Within the ASD group mean duration of fixation increased on the whole scene and particularly on the mouth area, in R50 compared to RT. Children with mild autism spent more time looking at the face than the two other groups of ASD children, and spent more time attending to the face and mouth as well as longer mean duration of visual fixation on mouth and eyes, at slow speeds (S50 and/or S70) than at RT one. CONCLUSIONS: Slowing down facial dynamics enhances looking time on face, and particularly on mouth and/or eyes, in a group of 23 children with ASD and particularly in a small subgroup with mild autism. Given the crucial role of reading the eyes for emotional processing and that of lip-reading for language processing, our present result and other converging ones could pave the way for novel socio-emotional and verbal rehabilitation methods for autistic population. Further studies should investigate whether increased attention to face and particularly eyes and mouth is correlated to emotional/social and/or verbal/language improvements.

Postural effects of motion vision in young autistic children.

We present the first assessment of motion vision in childhood autism. Postural reactivity to visually perceived motion was measured in five autistic children and 12 normal controls of the same chronological age. Anteroposterior as well as total body sway occurring on a force platform in response to movements in the visual environment were compared. Autistic children were posturally more unstable than normal children and quite insensitive to visually perceived environmental motion. Some implications of this impairment for sensorimotor and social communication development in infantile autism are discussed.

Motion and emotion: a novel approach to the study of face processing by young autistic children.

The specificity of facial processing impairment in autistic children, particularly in the domain of emotion, is still debated. The aim of our study was to assess the influence of motion on facial expression recognition in young autistic children. Thirteen autistic children (M age: 69.38 months) were matched for gender and developmental level with a control group of 13 normal children (M age: 40.53 months). They were compared on their ability to match videotaped "still," "dynamic," and "strobe" emotional and nonemotional facial expressions with photographs. Results indicate that children with autism do not perform significantly worse than their controls in any of our experimental conditions. Compared to previous studies showing lower performance in autistic than in control children when presented with static faces, our data suggest that slow dynamic presentations facilitate facial expression recognition by autistic children. This result could be of interest to parents and specialists involved in education and reeducation of these children.

[Usefulness of the concepts of "epigenesis" and "auto-organization" to understand the autistic child syndrome]. / Utilité des concepts d'"épigenèse" et d'"auto-organisation" pour la compréhension des syndromes autistiques de l'enfant.

This article, based more on speculation than on clinical work, aims at clarifying the nature of child autistic syndromes using two elements: epigenetic findings concerning the construction of human brain and the idea that there is a self-organizing development and functioning of the living. First initiated by H. Atlan (1979) and A. Bourguignon (1981), this approach could lead to a fruitful understanding of autistic disturbances, both consistent with developmental neurobiology and psychodynamics. This approach integrates clinical, paraclinical, follow-up and experimental data related to these disturbances. It also might lead to new therapeutic approaches which we are in the process of investigating.

[Traditional medicine and psychiatry: apropos of 3 experiences in Senegal, New Caledonia and Nepal]. / Médecines traditionnelles et psychiatrie: a propos de trois expériences, au Sénégal, en Nouvelle-Calédonie et au Népal.

The authors describe by turns their experience about indigenous medicine in Senegal, in New-Caledonia and in Nepal. They show that these indigenous medicines have common fundamental characteristics, although these various cultures are not linked together by their history. They compare these ways of thinking with occidental scientific medicine, and with the way of thinking of psychoanalysis.